text:
Subclass of:
375 - Pulse or digital communications
Patent class list (only not empty are listed)
Deeper subclasses:
|Class / Patent application number
|Number of patent applications / Date published
|Signal noise
|Phase error or phase jitter
|With indicator
|Data rate
|WIRELESS DEVICE AND COMMUNICATION CONTROL PROGRAM - A wireless device includes a channel covariance matrix calculating unit that calculates a covariance matrix based on a channel matrix estimated based on radio signal transmitted from a transmitting station. The wireless device further includes a first metric calculating unit that calculates a first metric based on the calculated covariance matrix. The wireless device further includes a W
|Capturing and Using Radio Events - In one embodiment a method includes, collecting in-phase/quadrature (I/Q) data representing energy detected by a radio in a frequency band, performing a fast Fourier transform (FFT) on the I/Q data resulting in a stream of FFT blocks, identifying using the stream of FFT blocks a pulse in the frequency band, recording in a radio events record (RER) a plurality of radio events and corresponding timestamps that are indicative, respectively, of a type and time of individual state changes in the radio during the collecting step, and, for example, using at least two of the radio events to identify, in the time domain, a beginning time and end time of the pulse detected in the stream of FFT blocks.
|SYSTEM AND METHOD FOR FAULT DETECTION AND LOCALIZATION IN TIME SERIES AND SPATIAL DATA - A method for fault detection and localization calls for obtaining a data set, smoothing the data set, identifying a plurality of split points within the data set, fitting a piecewise linear function to the plurality of split points; and determining a residual between the function and the smoothed data set. Related systems and computer program products are disclosed and claimed.
|POWER DETECTOR AND WIRELESS DEVICE - According to one embodiment, a power detector includes a reference voltage generator, a square signal generator, a detection circuit, and an output circuit. The reference voltage generator is configured to receive a bias voltage and generate a reference voltage. The square signal generator is configured to receive a voltage having a high frequency input voltage superimposed on the bias voltage and output a signal including the reference voltage, a voltage of a square of the high frequency input voltage, and a high-frequency signal. The detection circuit has a first lowpass filter, a first operational amplifier configured to amplify error between an output voltage of the first lowpass filter and the reference voltage and output the error as a control voltage, and a feedback transistor configured to feed a feedback current according to the control voltage back to an output terminal of the square signal generator.
|METHOD AND APPARATUS FOR REDUCING PEAK TO AVERAGE POWER RATIO USING PEAK WINDOWING - A method and apparatus for reducing a Peak to Average Power Ratio (PAPR) using peak windowing is provided. In the apparatus, an absolute value calculator calculates an absolute value of an input signal, a subtractor subtracts a predetermined clipping threshold level from the absolute value, a smoothing unit performs smoothing on the subtracted signal according to a predetermined smoothing scheme and outputs a first smoothed signal, an adder adds the first smoothed signal to the clipping threshold level, an inverse calculator outputs a second smoothed signal by multiplying the clipping threshold level by an inverse of the added signal, and a multiplier outputs a final PAPR-reduced signal by multiplying the input signal by the second smoothed signal. The method and apparatus address an overcompensation problem while processing signals having a large bandwidth and a high data rate without delay, thereby minimizing the clipping influences on Bit Error Rate (BER) and Adjacent Channel Leakage Ratio (ACLR) performances.
|CO-CHANNEL INTERFERENCE AND ADJACENT CHANNEL INTERFERENCE DETECTION AND SUPPRESSION - Methods having corresponding apparatus and computer-readable media comprise: receiving an input signal, wherein the input signal includes a DVB-H signal; detecting co-channel interference (CCI) in the signal; suppressing the CCI in the input signal; and demodulating the DVB-H signal after suppressing the CCI.
|METHOD AND APPARATUS FOR REMOTELY TESTING A DIGITAL SUBSCRIBER LINE ACCESS MULTIPLEXER - A system and method for testing a modem of a digital subscriber line access multiplexer (DSLAM) includes a pair of modems communicatively coupled to each other by way of a communications path that includes a first DSL communication medium connected to one modem, a second DSL communication medium connected to the other modem, which is part of the DSLAM, and an Ethernet medium connected between the first and second DSL modems. DSL signals can be dispatched from the first (or second) modem via the first (or second) DSL communication medium for receipt by the second (or first) DSL modem via the second (or first) DSL communication medium, whereupon, DSL signals passing from the first DSL communication medium to the second DSL communication medium, or vice versa, are converted into Ethernet packets for transmission over the Ethernet medium and then back into DSL signals.
|APPARATUS FOR EVALUATING SIGNAL TRANSMISSION SYSTEM, METHOD OF EVALUATING SIGNAL TRANSMISSION SYSTEM, AND STORAGE MEDIUM STORING PROGRAM FOR EVALUATING SIGNAL TRANSMISSION SYSTEM - A signal transmission system evaluation apparatus acquires statistics about a variation in a characteristic value and a limit value of the characteristic value corresponding to a given range of variation, with respect to each of the characteristic values which represent characteristics of the components. The apparatus calculates a probability distribution with respect to each of the characteristic values, based on the statistic acquired, calculates an eye-opening of the signal transmission system in case that the characteristic value is the limit value, makes an adjustment of the limit value. The apparatus calculates a yield rate of the signal transmission system based on the probability distribution and the limit value.
|Distortion and aliasing reduction for digital to analog conversion - Distortion and aliasing reduction for digital to analog conversion. Synthesis of one or more distortion terms made based on a digital signal (e.g., one or more digital codewords) is performed in accordance with digital to analog conversion. The one or more distortion terms may correspond to aliased higher-order harmonics, distortion, nonlinearities, clipping, etc. Such distortion terms may be known a priori, such as based upon particular characteristics of a given device, operational history, etc. Alternatively, such distortion terms may be determined based upon operation of a device and/or based upon an analog signal generated from the analog to conversion process. For example, frequency selective measurements made based on an analog signal generated from the digital to analog conversion may be used for determination of and/or adaptation of the one or more distortion terms. One or more DACs may be employed within various architectures operative to perform digital to analog conversion.
|Cyclostationary Signal Detection in the Angular Domain for Communication Systems - Apparatuses and methods for providing efficient spectrum sensing and signal detection using cyclostationary based spectrum sensing algorithms. A method embodiment is provided, comprising: receiving input samples of a signal having expected predetermined properties; transforming the input samples to angular form and obtaining data samples corresponding to at least one angle vector; performing a cyclostationarity test on the at least one angle vector, the cyclostationarity test being done entirely in an angular domain; wherein the cyclostationarity test comprises testing the at least one angle vector for a non-uniform distribution, the non-uniform distribution of the at least one angle vector indicating cyclostationarity in the input samples; and where cyclostationarity in the input samples is determined, refraining from transmitting radio frequency signals over an air interface at a frequency corresponding to the received signal. Apparatuses for implementing the methods are also disclosed.
|APPARATUS AND METHOD FOR DETERMINING MIMO/DSM OPERATING MODE - Provided is a data transmission system that may determine a multiple input multiple output dynamic spectrum management (MIMO-DSM) operation mode of a base station based on information associated with a data transmission route and a computational capability of each base station. A terminal may generate feedback information based on a cooperation level between base stations and may transmit the generated feedback information to a serving base station. The serving base station may select terminals that may receive data from among a plurality of terminals through a MIMO-DSM algorithm and a user scheduling based on the feedback information.
|DL MU-MIMO operation in LTE-A - Techniques for scheduling UEs are described. In one design, a scheduler (e.g., for a cell) may receive channel direction information (CDI) and channel strength information (CSI) from a plurality of UEs. In one design, the CDI from each UE may include at least one eigenvector, and the CSI from each UE may include at least one singular value corresponding to the at least one eigenvector. The scheduler may schedule at least one UE among the plurality of UEs for data transmission based on the CDI and CSI from the plurality of UEs. The scheduler may select the at least one UE based on a metric related to signal-to-leakage ratio (SLR), or spectral efficiency, etc. In one design, the scheduler may evaluate the performance of different sets of UEs to determine whether to schedule one UE for single-user MIMO or multiple UEs for multi-user MIMO.
|CIRCUIT ARRANGEMENT, APPARATUS AND PROCESS FOR THE SERIAL SENDING OF DATA VIA A CONNECTION CONTACT - The invention relates to an integrated circuit arrangement with connection contacts for the serial exchange of data and/or signals with external components and apparatuses and with a control apparatus and/or a serial interface for the clocked receiving of data by means of a signal voltage on such a connection contact, which voltage is modulated between at least one low, one middle and one high voltage state. The control apparatus and/or the interface are designed in such a manner that data is sent in a sending mode via the connection contact in that the switching apparatus, after having received a slope changing in particular from the middle voltage state into in particular the higher or the lower voltage state, pulls the voltage state into the in particular opposite lower or higher voltage state. Furthermore, the invention relates to an apparatus and a process for operating such a circuit arrangement.
|CALIBRATING JITTER - Calibrating jitter in a communication channel between test equipment and a connection for a device under test (DUT) includes sampling test data in the communication channel at about a point of the connection to produce sampled data, where the test data travels through the communication channel at a first rate, and where the test data is sampled at a second rate that is less than the first rate, determining a first amount of jitter in the sampled data relative to the test data, and determining a second amount of jitter at about the point of connection based on the first amount of jitter.
|ADJACENT CHANNEL INTERFERENCE MITIGATION DURING THE ACQUISITION PHASE IN OFDM COMMUNICATIONS - Methods and apparatuses for adjacent channel interference mitigation during the acquisition phase in OFDM communications use a Discrete Fourier Transform (DFT) to detect the energy of a received channel without adding latency. In particular embodiments, the communications are vehicular OFDM communications and the DFT is a sliding DFT of variable length. In a typical acquisition procedure, RF gain is set based on received total energy, which includes energies of the received and adjacent channels. A modified state machine waits until the energy of a received channel is detected, then the RF gain is adjusted to fulfill an enhanced adjacent channel rejection criterion requirement.
|RADIO WAVE PROPAGATION CHARACTERISTIC ESTIMATION APPARATUS, METHOD, AND COMPUTER PROGRAM - To estimate radio wave propagation characteristics with high estimation accuracy, even when used for a variety of purposes. An estimation technique determining unit determines, for each of groups classified in accordance with a measurement condition, an optimum radio wave propagation characteristic estimation technique from among a plurality of radio wave propagation characteristic estimation techniques, based on an actual measured value of radio waves. A radio wave propagation characteristic estimating unit discriminates a group corresponding to the given measurement condition, sets the optimum radio wave propagation characteristic estimation technique corresponding to the discriminated group, and estimates the radio wave propagation characteristics in accordance with the set radio wave propagation characteristic estimation technique.
|APPARATUSES AND METHODS FOR SETTING AN ADAPTIVE FREQUENCY BAND FOR POWER LINE COMMUNCIATION - Apparatuses and methods relating to power line communication are disclosed, and in particular, to an adaptive frequency band for power line communication. A power line communication device is disclosed. The power line communication device comprises a cutoff frequency estimator configured for estimating a cutoff frequency for communication in a power line communication network, and a processor operably coupled with the cutoff frequency estimator. The processor is configured to adaptively select boundaries of a frequency band in response to the estimated cutoff frequency. Other apparatuses and methods are disclosed.
|HIGH-SPEED SIGNALING SYSTEMS WITH ADAPTABLE PRE-EMPHASIS AND EQUALIZATION - A signaling system includes a pre-emphasizing transmitter and an equalizing receiver coupled to one another via a high-speed signal path. The receiver measures the quality of data conveyed from the transmitter. A controller uses this information and other information to adaptively establish appropriate transmit pre-emphasis and receive equalization settings, e.g. to select the lowest power setting for which the signaling system provides some minimum communication bandwidth without exceeding a desired bit-error rate.
|Method of Detecting a Direction of Arrival of at Least One Interference Signal and System to Carry Out Said Method - A method of detecting a direction of arrival of at least one interference signal interfering a wanted signal in a plurality of received signals involves receiving, by a number of antennas of an antenna array, a number of signals, identifying an interference signal in the received signals, applying a beam forming signal processing technique to the identified interference signal, and detecting the direction of arrival from the results of the beam forming signal processing.
|SYSTEM AND METHOD FOR DISCOVERING AND VERIFYING A HYBRID FIBER-COAXIAL TOPOLOGY IN A CABLE NETWORK ENVIRONMENT - A method in an example embodiment can include polling a first cable modem in a cable network and receiving a first response message from the first cable modem identifying a downstream frequency detected by the first cable modem. The method further includes determining the downstream frequency is split between at least two fiber nodes and determining a cable modem termination system (CMTS) service group topology, where the topology includes the at least two fiber nodes. In specific embodiments, determining that the downstream frequency is split is based on at least the first response message from the first cable modem and a second response message from a second cable modem. In more specific embodiments, the method includes constructing a hybrid fiber-coaxial (HFC) topology map of the cable network based on at least the first and second response messages, where the HFC topology map indicates the CMTS service group topology.
|METHOD FOR TESTING SENSITIVITY OF A DATA PACKET SIGNAL TRANSCEIVER - A method for using a test data packet signal to test a data packet signal transceiver device under test (DUT) having an operating characteristic defined by a data packet error rate (PER) as a function of data packet signal power (PWR). The test data packet signal power is varied and a test PER is computed as a function of DUT response data packets and test data packets until a measured test PER or a computed test PER extrapolated from measured PERs is equal to a predetermined PER less than and greater than maximum and minimum PERs, respectively.
|GROUP DELAY CALIBRATION METHOD FOR POWER AMPLIFIER ENVELOPE TRACKING - An open loop envelope tracking system calibration technique and circuitry are proposed. A radio frequency power amplifier receives a modulated signal. An envelope tracker power converter generates a modulated power amplifier supply voltage for the radio frequency power amplifier based on a control signal derived from the modulated signal. A first output power and a second output power of the radio frequency power amplifier are measured when the control signal is respectively delayed by a first delay period and a second delay period. A sensitivity of the output power of the radio frequency power amplifier is near a maximum near the first delay period and the second delay period. The first delay period and/or the second delay period are adjusted until the first output power substantially equals the second output power. The first delay period and the second delay period are used to obtain a calibrated fine tuning delay offset.
|TIME DELAY AND DISTANCE MEASUREMENT - A method for measuring time delay and distance may include providing an electromagnetic radiation carrier frequency and modulating one or more of amplitude, phase, frequency, polarization, and pointing angle of the carrier frequency with a return to zero (RZ) pseudo random noise (PN) code. The RZ PN code may have a constant bit period and a pulse duration that is less than the bit period. A receiver may detect the electromagnetic radiation and calculate the scattering profile versus time (or range) by computing a cross correlation function between the recorded received signal and a three-state RZ PN code kernel in the receiver. The method also may be used for pulse delay time (i.e., PPM) communications.
|METHOD AND DEVICE FOR DATA PROCESSING IN A DIGITAL SUBSCRIBER LINE ENVIRONMENT - A method and a device for data processing in a digital subscriber line environment. A virtual noise level for a digital subscriber line is determined based on measurement information of at least one network element connected to the digital subscriber line.
|OFDM CHANNEL ESTIMATION SYSTEM AND METHOD COMPONENTS - Channel estimation for high mobility OFDM channels is achieved by identifying a set of channel path delays from an OFDM symbol stream including carrier data, inter-channel interference noise and channel noise; determining the average channel impulse response for the identified set of channel path delays in each symbol; generating a path delay curvature for each channel path delay in each symbol based on stored average channel impulse responses for the identified channel path delays; estimating the carrier data in the symbols in the OFDM symbol stream in the presence of inter-channel interference noise and channel noise from the OFDM symbol steam and the average impulse responses for the identified channel path delays; reconstructing the inter-channel interference noise in response to the path delay curvature, the identified set of channel path delays and estimated carrier data to produce a symbol stream of carrier data and channel noise with suppressed inter-channel interference noise.
|Test System - A test system for testing an electronic device is disclosed. The test system includes a signal generator for generating an input signal, a signal splitter for splitting the input signal into a first splitting signal and a second splitting signal, a micro control unit for generating a first control signal and a second control signal, a first transmission interface for transmitting the first splitting signal and the first control signal, a second transmission interface for transmitting the second splitting signal and the second control signal, and a first signal adjustment unit for transforming the first splitting signal to a first test signal for test according to the first control signal.
|RECEIVER AND METHOD OF RECEPTION QUALITY MEASUREMENT USED IN WIRELESS NETWORK - A receiver includes: a measurement unit configured to measure received power of a pilot signal symbol included in a received signal and generate a received power measurement value for each of a plurality of measurement periods; and a calculator configured to calculate received power by calculating a weighted average of a plurality of received power measurement values obtained by the measurement unit based on the numbers of the pilot signal symbols that are included in respective measurement periods.
|Method and Apparatus for Quantifying Characteristics of a Received Serial Data Stream - A data stream monitor includes an analog front end (AFE) and a digital state machine. The AFE receives recovered clock and data signals at a first rate. The AFE uses the recovered clock and a phase interpolator to generate a phase-adjusted clock signal at a second rate slower than the first rate. The AFE uses a detector operating with the phase-adjusted clock signal to generate a representation of the data signal generated from comparisons of the data signal with two reference voltages. A logical combination of the results from the comparisons generates a signal that identifies when the data signal voltage is near the common-mode voltage. The digital state machine generates a strobe signal at a third rate slower than the second rate. The strobe signal is used by the AFE to sample the signal. The sample is forwarded to the digital state machine where it is stored.
|Controlling a Power Amplifier Based on Transmitter Output Emissions
|METHOD AND APPARATUS FOR METALLIC LINE TESTING OF A SUBSCRIBER LINE - A method for performing metallic line testing on a communication system is provided. The communication system includes an isolation transformer disposed between a provider circuit operable to provide a digital subscriber line signal and a subscriber circuit. The isolation transformer has a center tap. A test signal is injected at the center tap. A response of the subscriber circuit to the test signal is sensed.
|Processing Signals - Signals are received, over a range of angles, at an input of a device. The signals include a primary signal with a principal direction of arrival and an interfering signal with a respective interfering direction of arrival at the input. Measurements are determined for the received signals over the range of angles. Each measurement relates to a particular angle and indicating the energy of the received signals which are received from the particular angle. For each angle over the range of angles, a value is removed from the measurement for that angle, the value being based on the minimum of: (i) the energy of the measurement for that angle, and (ii) the energy of a corresponding measurement for a corresponding angle mirrored around the principal direction of arrival, whereby the remaining values of the plurality of measurements are indicative of said at least one interfering direction of arrival.
|METHOD AND APPARATUS FOR DETERMINING UE MOBILITY STATUS - A radio user equipment (UE) mobility status is determined in a communications node. UE mobility status measurements associated with the UE communicating over a radio channel are performed. The UE mobility status corresponds to a degree of variation of the radio channel over time. Channel characteristics of the radio channel at a first time and at a second later time are determined. Based on the determined channel characteristics, a channel characteristic error metric is determined and compared to a predetermined threshold. The UE mobility status is determined based on one or more iterations of the threshold comparison.
|COMMUNICATING CHANNEL STATE INFORMATION USING PREDICTIVE VECTOR QUANTIZATION - Techniques are generally described here for communicating channel state information using predictive vector quantization. In some examples, a method may include measuring channel state information based, at least in part, on signals received over a communications channel. An error vector may be calculated between the measured channel state information and predicted channel state information. The error vector may be quantized, and subsequent channel state information may be predicted based, at least in part, on the quantized error vector.
|CODE EVALUATOR, CODE EVALUATION METHOD, RADIO COMMUNICATION SYSTEM, BASE STATION AND MOBILE STATION - The present invention relates to a code evaluation method comprising the steps of computing an auto-correlation function from a generated code; computing an evaluation reference value for determining quality of the generated code based on the auto-correlation function and a weighting factor determined depending on the evaluation reference value; and determining the quality of the generated code based on the evaluation reference value.
|Programmable duty cycle distortion generation circuit - An integrated circuit is provided comprising: a serial transmitter, a serial receiver and a serial connection providing communication between the serial transmitter and the serial receiver. The integrated circuit further comprises a duty cycle distortion circuit so that the integrated circuit can be stress tested by distorting the duty cycle of a signal within the integrated circuit.
|Signal Evaluation and Adjustment - A method of assessing a received signal acquired through a physical channel and comprising a pilot channel, the method comprising estimating from an oversampled version of the received signal an oversampled response for the physical channel and quantifying noise in the received signal using the oversampled received signal and the oversampled channel response.
|Method and Apparatus for Estimating Clock Deviations, for Virtual Synchronization of Free-Running Clocks and for Determining the Position of a Movable Object - In a method for estimating a deviation between a free-running transmitter clock and a reference clock, at a receiver stationary with respect to a transmitter, a transmitter signal generated by the transmitter on the basis of the transmitter clock is received. On the basis of the reference clock, a time of arrival of the transmitter signal and a beat phase of the transmitter signals carrier is determined. On the basis of a clock error model, the time of arrival and the beat phase, the deviation between the transmitter clock and the reference clock is estimated. The clock error model is derived by fitting a correlation function of a stochastic model to a measured auto correlation function of the transmitter clock. Deviations for a plurality of transmitters may be estimated and the transmitters may be virtually synchronized based on the estimations.
|APPARATUS AND METHOD FOR CONTROLLING TRANSMIT POWER IN HUMAN BODY COMMUNICATION SYSTEM - An apparatus and method for controlling Transmit (Tx) power when a portable terminal performs human body communication with a counterpart portable device are provided. The apparatus includes a voltage manager for determining whether the Tx power needs to be changed based on an output voltage that is based on a current that varies according to a distance between an electrode of a portable terminal and an electrode of a counterpart portable terminal, and changes the Tx power according to a result of the determination.
|Method to Prevent Phenomenon in Vector Modulator Transmitter - One embodiment of the present invention relates to an apparatus for preventing remodulation in a transmission chain. A first offset generation circuit selectively introduces a first frequency offset into in-phase (I) and quadrature phase (Q) equivalent baseband signals. A second offset generation circuit selectively introduces a second frequency offset into an oscillator output signal. The frequency of the offset oscillator output signal is divided by a divider to form offset local oscillator signals, which are provided to up-conversion mixers that modulate the offset equivalent baseband signals onto the offset local oscillator signals to generate a composite modulated output signal. The first and second frequency offsets are chosen to have values that cancel during modulation. However, because the second frequency offset shifts the offset oscillator output signal's frequency to a value that is no longer a harmonic of the composite modulated output signal's frequency, remodulation is prevented.
|Probing and Estimation of cross-coupling - Embodiments related to probing and estimation of cross-coupling in a Vector transmission system are described and depicted.
|Method and apparatus for improving quality of service for reception in digital television broadcast systems - A method of transmitting a digital data stream to a receiver unit. The method includes the steps of modulating a digital data stream in accordance with a modulation technique so as to generate a modulated digital data stream; providing the modulated digital data stream to a transmitter unit operable for transmitting the modulated digital data stream; receiving the transmitted digital data stream by the receiver unit, where the receiver unit generates signal reception data indicating the quality of reception of the modulated digital data stream; and providing the signal reception data indicating the quality of reception of the modulated digital data stream to a quality control processing unit via a communication channel, where the quality control processing unit analyzes the signal reception data to determine if the quality of reception of the modulation digital data stream by the receiver unit is below a predefined level, and if so, adjusts the modulation technique being applied so as to improve the quality of reception by the receiver unit.
|VECTOR SIGNAL MEASURING SYSTEM, FEATURING WIDE BANDWIDTH, LARGE DYNAMIC RANGE, AND HIGH ACCURACY - A new measurement system, with two receiver channels per measurement port, has been developed that provides absolute magnitude and absolute phase relationship measurements over wide bandwidths. Gain ranging is used at RF to provide optimum noise performance and a swept YIG preselector filter is used to avoid spurious signals. A new absolute vector error correction method is used to calibrate the measurement system in order to allow for absolute vector measurements, and it also removes the time-varying responses caused by the swept YIG preselector filters. A quasi-reciprocal mixer with a characterized non-reciprocal ratio is used to provide the absolute calibration standard. The two receiver channels can be adapted to a wide variety of applications, including wide bandwidth vector signal analyzer measurements, mixer measurements, and harmonic measurements. The two-channels can also be used as an absolute calibrated transmitter/reflectometer.
|LINK ADAPTATION SYSTEMS AND METHODS - The present application discloses systems and methods for adjusting a back-off value for a rank. In some embodiment, the method includes the steps of: (a) determining whether the rank is underutilized and (b) in response to determining that the rank is underutilized, decreasing the back-off value as a function of time while the rank remains underutilized.
|NONLINEAR DEVICE DETECTION - Data is collected and interpreted in response to one or more transmitted signals to determine if an interfering device is present. If an interfering device is present, a message is generated and presented to a user indicating, for example, that the installation of a micro-filter is appropriate. The system can then determine if the micro-filter was installed properly and, for example, commence communication or, if the micro-filter(s) did not solve the problem, initiate communication with or contact a technician.
|MODULATION APPARATUS, TEST APPARATUS AND CORRECTION METHOD - Provided is a modulation apparatus that quadrature modulates a periodic signal, comprising an I-side signal output section that outputs an I-component signal; a Q-side signal output section that outputs a Q-component signal; a quadrature modulator that quadrature modulates the periodic signal with the I-component signal and the Q-component signal; an I-side correcting section that corrects the I-component signal according to an error of the quadrature modulator; and a Q-side correcting section that corrects the Q-component signal according to the error of the quadrature modulator.
|DEVICE FOR BROADBAND RECEPTION BY AUTOTRANSPOSITION AND APPLICATION TO THE DETECTION AND CHARACTERIZATION OF RADIOELECTRIC EMISSIONS - Use of an antennal base formed of two antennas which pick up the emissions present and produce two radioelectric signals S1 and S2. These two signals are used to produce at least one intermediate-frequency signal Fl by demodulation of one of the two signals by the other (autotransposition). The demodulation is carried out by firstly transposing one of the signals, S1 for example, around a given frequency F1, the signal S2 being preserved around its initial central frequency F
|WIRELESS RECEIVER DEVICE AND DIRECTIVITY CONTROL METHOD - Disclosed is a radio reception apparatus that can prevent deterioration of reception quality, even when a delayed wave having a delay exceeding the length of a guard interval is present in the SFN environment. In this apparatus, OFDM receiver (
|Method and System for Using a Multi-RF Input Receiver for Diversity Selection - A method for processing signals in a receiver includes receiving a plurality of wireless signals via a plurality of M receive antennas coupled to M corresponding signal amplifiers. The method may also include measuring corresponding signal strengths of M signals generated when each of M phase-shifters is coupled to each of the M receive antennas, while one or more of the M signal amplifiers are disabled. One of the M generated signals may be selected for processing without the use of an antenna switch, where the selecting may be based on the measured signal strength. Each of the plurality of received wireless signals may be amplified prior to the measuring. One or both of an in-phase (I) component and/or a quadrature (Q) component may be generated for each of the M generated signals.
|SIGNAL RECEPTION APPARATUS AND SIGNAL RECEPTION METHOD - One embodiment provides a signal reception apparatus including: a reception module configured to receive a signal; a storing module configured to store information regarding a characteristic of the received signal; a determination module configured to read out the stored information and to determine a parameter value corresponding to the read-out information; a discrimination module configured to discriminate a noise contained in the signal, based on the signal and the determined parameter value; and an identification module configured to identify the noise contained in the signal, based on a discrimination result by the discrimination module.
|Joint Adaptive Bias Point Adjustment and Digital Pre-Distortion for Power Amplifier - One embodiment of the present invention relates to a method and apparatus are provided herein for reducing the power consumption of a transmission chain while maintaining an acceptable figure of merit (e.g., linearity). In one embodiment, an adaptive biasing element is configured to perform adaptive biasing to reduce current consumption of a transmission chain by adjusting the operating point of one or more transmission chain elements (e.g., power amplifier, mixer, etc.). However, since adaptive biasing may reduce the linearity of a transmitted signal, its use is limited by the degradation of figure of merit caused by the introduced non-linearities. Accordingly, a pre-distortion element may be configured to perform adaptive digital pre-distortion (DPD) on a transmission chain input signal to account for non-linearities generated through the adaptive biasing, therefore allowing the adaptive biasing to further reduce the current consumption while maintaining an acceptable figure of merit.
|WAVEFORM SHAPING DEVICE AND ERROR MEASUREMENT DEVICE - The object of the present invention is to provide a waveform shaping device and an error measurement device which can perform a waveform shaping operation with the sufficient amplitude margin, even if the mark ratio of the inputted data signal is significantly varied and the amplitude of the inputted data signal is decreased. The waveform shaping device according to the present invention comprises a voltage detector (
|PROGRAMMABLE PREAMBLE SYSTEM AND METHOD - A system includes a first communication device and a second communication device. The first communication device includes a programmable region. The programmable region of the first communication device is programmed so that an associated signal includes a number of preamble cycles. The second communication device also can include a programmable region. The programmable region of the second communication device can be programmed so that an associated signal includes a number of preamble cycles. The number of preamble cycles can be based on a variety of factors, such as the topology or implementation of the system. In an embodiment, the number of preamble cycles is associated with a data strobe signal, and data is not read or written in response to the data strobe signal until all of the preamble cycles have been transmitted and received.
|SELF-TESTING APPARATUS AND METHOD FOR PHASE ADJUSTMENT CIRCUIT - A signal inversion unit inverts an adjustment pattern signal input as received data. A clock adjustment control circuit acquires a first TAP value adjusted and obtained when a phase adjusting operation is performed on a clock adjustment circuit in a state in which the adjustment pattern signal is not inverted, a first detection frequency of the adjustment pattern signal in a runtime of the operation, a second TAP value adjusted and obtained when the phase adjusting operation is performed in a state in which the adjustment pattern signal is inverted by the signal inversion unit, and a second detection frequency of the adjustment pattern signal in the runtime of the operation. A controller tests an operating state of the phase adjusting operation based on the first and second TAP values and the first and second detection frequencies of the adjustment pattern obtained by the clock adjustment control circuit.
|Echo profile probe - In an orthogonal frequency division multiplex (OFDM) communication network, a node transmits an echo profile probe to other nodes in the network. The echo profile probe is a message that allows characterization of the unique echo profile through the communication channel between each node pair. The echo profile is used to calculate the cyclic prefix length needed for optimum communication from one node to the other.
|SIGNAL TRANSMITTER AND SIGNAL TRANSMITTING METHOD FOR TRANSMITTING SPECIFIC DATA BIT WITH DIFFERENT PREDETERMINED VOLTAGE LEVELS - An exemplary signal transmitter includes a checking circuit and a driving circuit. The checking circuit is arranged for checking a plurality of successive data bits to be transmitted and accordingly generating a checking result. The driving circuit is arranged for referring to the checking result and transmitting a specific data bit with a plurality of different predetermined voltage levels. An exemplary signal transmitting method includes: checking a plurality of successive data bits to be transmitted, and accordingly generating a checking result; and transmitting a specific data bit with a plurality of different predetermined voltage levels according to the checking result.
|ADAPTIVE TRACKING STEPS FOR TIME AND FREQUENCY TRACKING LOOPS - A wireless communications method is provided. The method includes analyzing one or more channel conditions from a wireless communication and automatically adjusting a frequency tracking loop gain or a time tracking loop gain in view of the channel conditions.
|Method and Device for Identifying at Least One Communication Channel with an Incident Signal - Method for identifying within an incident signal at least one frequency communication channel, said incident signal being received on a wireless apparatus, comprising determining a power spectral density (PSD) of that incident signal and identifying said at least one channel from said PSD. The said PSD determination comprises storing temporal samples of said incident signal received during a predetermined duration and performing a first Discrete Fourier Transform (DFT) processing on said stored samples.
|PERIODIC CALIBRATION FOR COMMUNICATION CHANNELS BY DRIFT TRACKING - A method and system that provides for execution of a first calibration sequence, such as upon initialization of a system, to establish an operation value, which utilizes an algorithm intended to be exhaustive, and executing a second calibration sequence from time to time, to measure drift in the parameter, and to update the operation value in response to the measured drift. The second calibration sequence utilizes less resources of the communication channel than does the first calibration sequence. In one embodiment, the first calibration sequence for measurement and convergence on the operation value utilizes long calibration patterns, such as codes that are greater than 30 bytes, or pseudorandom bit sequences having lengths of 2
|RADIO EQUIPMENT CONTROLLER, RADIO CONTROL METHOD, RADIO STATION, AND RADIO COMMUNICATION SYSTEM - A radio equipment controller includes a calculator that calculates a delay amount by subtracting from a given maximum delay amount an internal delay amount of a radio equipment and a delay amount of a cable, the radio equipment modulating and transmitting orthogonal frequency division multiplexing (OFDM) symbols, and the cable connecting the radio equipment and the radio equipment controller that creates the OFDM symbols, a detector that detects a beginning of the OFDM symbols from data that is inputted into a buffer that stores data of the OFDM symbols, and a delay controller that determines a transmission timing of the OFDM symbols so that the transmission timing of the beginning of the OFDM symbols becomes a timing that is delayed by the calculated delay amount after a reference signal with a specific period.
|ULTRA LOW POWER RF LINK - A receiver including a processor. A plurality of Fast Fourier Transforms of a plurality of signal segments of a signal can be determined by the processor. The plurality of Fast Fourier Transforms are stored. A frequency shift of the signal can be determined recursively based on the stored plurality of Fast Fourier Transforms of the plurality of signal segments.
|Method and Device for Predicting a Figure of Merit From a Distribution - Embodiments of the invention relate to methods and devices for predicting a figure of merit from a distribution at least including scalably normalizing the distribution to approximate a predetermined part of the normalized distribution.
|Circuit device including peak and average detectors - In a particular embodiment, a circuit device includes a peak detector to receive a signal and to generate peak output data related to the received signal and an average detector to generate average output data related to the received signal. The circuit device further includes a logic circuit to generate a data output related to the received signal based on the generated peak output data and the generated average output data.
|CREST FACTOR REDUCTION FOR A MULTICARRIER-SIGNAL WITH SPECTRALLY SHAPED SINGLE-CARRIER CANCELATION PULSES - A method for crest factor reduction of a multi-carrier signal is disclosed. The multi-carrier signal comprises a plurality of single-carrier signals, each single-carrier signal having signal-specific spectral properties. The method comprises identifying a peak in the multi-carrier signal and a time of occurrence of the peak and generating a plurality of cancellation pulses depending on the time of occurrence of the peak. A particular cancellation pulse of the plurality of cancellation pulses is associated with a particular single-carrier signal and cancellation pulse-specific spectral properties of the particular cancellation pulse substantially match the signal-specific spectral properties of the associated particular single-carrier signal. The method further comprises combining the plurality of cancellation pulses to form a combined cancellation pulse and applying the combined cancellation pulse to the multi-carrier signal to reduce the peak. A corresponding circuit and corresponding computer program products useable during manufacture and operation are also disclosed.
|CHANNEL ESTIMATION FOR OFDM-BASED WIRELESS COMMUNICATION SYSTEM USING SPARSELY SPACED PILOT SUBCARRIERS - A device and method for performing a channel estimation for an OFDM-based wireless communication system using sparsely spaced pilot subcarriers estimates missing pilot subcarriers in an interpolation window using pilot subcarriers that are outside of the interpolation window to produce estimated pilot subcarriers for the interpolation window. The pilot subcarriers in the interpolation window and the estimated pilot subcarrier are used to compute pilot channel estimates for the interpolation window, which are then used to derive data channel estimates for the interpolation window.
|Multiple Receivers in an OFDM/OFDMA Communication System - A signal receiver is configured to receive multiple time-domain input signals. A plurality of the input signals among the multiple time-domain input signals is selected and transformed into frequency-domain signals. The frequency-domain signals is shifted in phase by a negative value of a respective reference phase, and the phase-shifted signals is combined into one signal. The combined signal is then multiplied with a stored signal to generate a signal product and transformed into a time-domain signal.
|RECURSIVE IMPLEMENTATION FOR CALCULATION OF WHITENING MATRIX - Certain aspects of the present disclosure relate to techniques for recursive implementation of whitening matrix calculation based on functional reuse as a part of wireless receiver in a Long Term Evolution (LTE) wireless system.
|CIR-BASED AND SSC-BASED FTL/TTL/CHANNEL ESTIMATION - Methods and systems are disclosed for channel estimation and frequency tracking in mobile communication systems. Particularly, various ways of using the time domain impulse channel response based on the staggered frequency domain pilot tones are presented that enable rapid frequency error estimation and frequency tracking control. A mathematical model is developed that provides a convenient metric for evaluating tolerable frequency error, as well as modes for switching between CIR-based and SSC-based frequency tracking.
|Ethernet Traffic Emulation Using Ramped Traffic Generation Techniques - The invention relates to a testing system for generating a plurality of independently controllable streams of Ethernet frames, e.g. voice, data and video, in which the bandwidth utilization thereof can be held constant or ramped up to test the effects thereof on the other streams.
|EQUALIZER LOCK DETECTION BASED ON THE LOCATION OF RECEIVED SIGNAL POINTS - An ATSC (Advanced Television Systems Committee-Digital Television) receiver comprises an equalizer and a lock detector. The equalizer provides a sequence of received signal points from a constellation space, the constellation space having an inner region and one, or more, outer regions. The lock detector determines equalizer lock as a function of the number of received signal points falling in the one, or more, outer regions.
|Echo Profile Probe - In an orthogonal frequency division multiplex (OFDM) communication network, a node transmits an echo profile probe to other nodes in the network. The echo profile probe is a message that allows characterization of the unique echo profile through the communication channel between each node pair. The echo profile is used to calculate the cyclic prefix length needed for optimum communication from one node to the other.
|BUILT-IN SELF-TEST CIRCUITRY - A method of generating at least one test sequence for testing a data connection, the method involving selectively combining by a logic function (
|APPARATUS AND METHOD FOR CONTROLLING COMMUNICATION - Apparatus and method for communication are provided. The solution comprises communicating on a synchronised shared channel having a frame structure comprising symbols; receiving from a network element a given number for each frame or sub frame, and during the given number of symbol periods in the beginning of a frame or sub frame measuring interference and making a decision whether to transmit or not during the rest of the symbol periods of the frame or sub frame.
|DYNAMIC DIGITAL PRE-DISTORTION SYSTEM - A Dynamic Digital Pre-Distortion (DDPD) system is disclosed to rapidly correct power amplifier (PA) non-linearity and memory effects. To perform pre-distortion, a DDPD engine predistorts an input signal in order to cancel PA nonlinearities as the signal is amplified by the PA. The DDPD engine is implemented as a composite of one linear filter and N−1 high order term linear filters. The bank of linear filters have programmable complex coefficients. To compute the coefficients, samples from the transmit path and a feedback path are captured, and covariance matrices A and B are computed using optimized hardware. After the covariance matrices are computed, Gaussian elimination processing may be employed to compute the coefficients. Mathematical and hardware optimizations may be employed to simplify and reduce the number of multiplication operands and other operations, which can enable the DDPD system to fit within a single chip.
|MEASUREMENT OF TIME OF ARRIVAL - Disclosed is a method of measuring time of arrival of a signal transmitted from a transmitter (
|TECHNIQUES AND SYSTEMS FOR COMMUNICATIONS BASED ON TIME REVERSAL PRE-CODING - Techniques, apparatuses and systems for providing communications based on time reversal of a channel impulse response of a pulse in a transmission channel between a transmitter and a receiver to enhance reception and detection of a pulse at the receiver against various effects that can adversely affect and complicate the reception and detection of the pulse at the receiver.
|APPARATUS AND METHOD FOR CHANNEL ESTIMATION USING COMPRESSIVE SENSING BASED ON TAYLOR SERIES EXPANSION - An apparatus and method for channel estimation comprising determining a channel impulse response using a Taylor series expansion with a plurality of Taylor series coefficients; determining a channel frequency response based on the channel impulse response; collecting the channel frequency response over a plurality of symbols to obtain a composite channel frequency response; generating a sensing matrix based on the Taylor series expansion; and determining the plurality of Taylor series coefficients based on the composite channel frequency response and the sensing matrix using compressive sensing channel estimation.
|INFORMATION PROCESSING APPARATUS AND INFORMATION GENERATION METHOD - An information processing apparatus includes: a reception unit configured to receive a packet string in which packet groups including data on a plurality of video frames and having an identifier indicating a beginning of the video frame assigned to respective packets including each initial part of the plurality of video frames are arranged in a video reproduction order; a counting unit configured to count a number of received packets corresponding to each of the plurality of video frames based on respective initial packets in the packet string; and a generation unit configured to generate video quality estimation information for each of the plurality of video frames to estimate a quality of the video in which the plurality of video frames are decoded on a reception terminal based on the number of received packets corresponding to each of the plurality of video frames.
|Technique for Rate Matching in a Data Transmission System - A technique for rate matching a bit stream (c
|RECEIVING APPARATUS AND RECEIVING METHOD - A receiving apparatus includes a converting unit that multiplies first and second reception signal points for the respective first and second reception signals by a matrix and outputs resulting converted first and second reception signal points; a number-of-candidates determining unit that determines a number of candidates for at least first transmission-signal candidate points, based on a reception quality for the first and second reception signals; and an estimating unit that selects, based on the converted first and second reception signal points, the first transmission-signal candidate points and second transmission-signal candidate points, the number of first transmission-signal candidate points corresponding to the determined number of candidates, and that estimates, as the first and second transmission signals, the first and second transmission-signal candidate points with which distances between the selected first and second transmission-signal candidate points and the corresponding converted first and second reception signal points are smallest.
|OFDM COMMUNICATION SYSTEM AND METHOD HAVING A REDUCED PEAK-TO-AVERAGE POWER RATIO - An OFDM system embeds sequence information in the transmitted signal that reduces peak average power ratio (PAP) with minimal impact on the overall system efficiency. A marker is embedded onto the transmitted information that is used to identify the combining (inversion) sequence at the receiver. In one embodiment, selected tones in a cluster are rotated when the corresponding phase factor rotates the cluster.
|TRANSMISSION CABLE CONTROLLER SYSTEM AND METHOD OF USE - The transmission cable controller system and method of use relates to a microprocessor controlled data cable that is capable of transmitting high volumes of data from many sources on as little as two copper conductors. The cable has the ability to monitor itself and its transmission path for chafing, corrosion, breakdown, and damage. Once a problem has been detected, the system can output a warning signal of any type (audible, visible or a remote warning line) to notify personnel that there is a problem.
|METHOD FOR REDUCING CHANNEL QUALITY INFORMATION IN OFDMA SYSTEMS - The present invention is directed to a method that includes determining
|METHODS AND DEVICES FOR PROCESSING SIGNALS TRANSMITTED VIA COMMUNICATION SYSTEM - A method for processing signals transmitted via a communication system includes: measuring a first parameter associated with a signal power of a first frequency band of a received signal; measuring a second parameter associated with a signal power of a second frequency band of the received signal, wherein the first frequency band and the second frequency band are not overlapped; comparing the first parameter with the second parameter to generate a comparison result; and detecting whether adjacent channel interference (ACI) exists in the communication system according to the comparison result to generate a detection result.
|PHASE DETECTOR, PHASE DETECTING METHOD, AND CLOCK-AND-DATA RECOVERY DEVICE - A phase detector includes a first sampling unit, a sampling module and a phase determining module. The first sampling unit is arranged for sampling a first data input signal to generate a first data signal according to a first clock signal. The sampling module includes a second sampling unit and a third sampling unit. The second sampling unit is arranged for sampling a second data input signal to generate a second data signal according to a second clock signal. The third sampling unit is arranged for sampling the second data signal to generate a third data signal according to the first clock signal. The phase determining module is arranged for generating a phase detecting result according to the first data signal and the third data signal.
|Method and Arrangement for Estimating the Quality Degradation of a Processed Signal - An objective quality assessment method for obtaining an improved estimate of a perceptual quality degradation of a processed signal, and an arrangement for executing such a method, is provided, which is executed on a processed signal and an associate reference signal. Both signals are split up into associated frame-pairs after into frames which either all or selected frame-pairs are processed further, by creating a reference residual signal and a processed residual signal for each frame-pair, calculating separate ratios of p-norms on both residual signals, and by calculating and storing a per-frame frame-pair quality estimate on the basis of the ratios of p-norms for each selected frame-pair. An objective per-signal quality estimate that is proportional to the perceptual quality Create degradation is then provided by aggregating the calculated per-frame-pair quality estimates.
|WIRELESS STATION, AN INTERFERENCE ESTIMATION METHOD, A WIRELESS COMMUNICATION SYSTEM AND A COMPUTER PROGRAM - A wireless station of the present invention includes: a synchronization unit configured to synchronize with a transmission suspension period of a transmitting station of a wireless system, a measurement unit configured to measure a reception level of a wireless signal of said transmitting station in a transmission period and a reception level in the transmission suspension period, and an interference estimation unit configured to estimate an amount of interference to another wireless system according to the measured reception level in the transmission suspension period and reception level in the transmission period.
|Method and Apparatus Providing Signal Metric for Transmitter - The present invention provides a method and associated apparatus providing a signal metric for a transmitter of a communication system. While the transmitter transmitting a signal with amplitudes scaled by scaling combinations selected from a plurality of scaling combination alternatives, the method including: providing a plurality of power terms, each power term corresponding to one of the scaling combination alternatives; and calculating the signal metric according to the plurality of power terms.
|APPARATUS AND METHOD FOR MEASURING RADIO QUALITY - A radio quality measurement apparatus extracts RS from a received signal on which FFT has been performed, and derives a FFT point number (N) of time samples to generate N
|SYSTEMS AND METHODS FOR BLIND EQUALIZATION IN A DIGITAL RECEIVER - A digital receiver system to recover signals from inter-symbol-interference includes a finite impulse response (FIR) filter using convolution to recover signals; and a channel estimator coupled to the FIR filter to estimate FIR coefficients, wherein the channel estimator uses a second order expectation and a fourth order expectation from a convolution to calculate error function.
|Calibrating Received Signal Measurements in a Digital Subscriber Line Device - Methods and apparatus for calibrating received signal measurements in a digital subscriber line (DSL) device are disclosed. In an exemplary method, a received signal level is measured for each of one or more subcarriers of a digital subscriber line signal and converted into a corresponding measured power level. A corrected received power level is calculated as a function of the measured power level, a reference input impedance value, a nominal loop impedance value, and a pre-determined input impedance value for the DSL device.
|Channel Quality Determination of a Wireless Communication Channel Based on Received Data - The invention refers to a method of determining a channel quality of a communication channel between a wireless transmitter and a wireless receiver, comprising receiving a transport block with one or a plurality of a modulation symbols (y
|OPTIMIZING DATA RATE OF MULTI-BAND MULTI-CARRIER COMMUNICATION SYSTEMS - Wired and wireless communication networks can be subject to noise and interference resulting data corruption. In a communication system comprising a first network device and a second network device, the first and the second network devices can be configured for optimizing the data rate of the communication system. On receiving a multi-band signal at the first network device from the second network device during a channel adaptation mode, the multi-band signal can be split into a plurality of independent frequency band signals. A performance measurement of a first of the plurality of frequency band signals corresponding to a lowest frequency band signal can be calculated. Communication parameters can be determined for each of the plurality of frequency band signals based on the performance measurement of the first of the plurality of frequency band signals. The communication parameters can be provided from the first network device to the second network device.
|DELAYING ANALOG SOURCED AUDIO IN A RADIO SIMULCAST - A method and apparatus is disclosed in which delay is applied to analog-sourced audio in a radio simulcast when the analog signal initially leads the digital signal. A radio receiver is configured to receive a simulcast radio program broadcast with an analog signal and a digital signal. The program content can be extracted from either the analog or digital signals, with the audio source eventually being blended to the digital signal. Audio is initially provided based on the analog signal. If the analog signal is initially leading the digital signal, delay is applied a data stream corresponding to the analog signal relative to a data stream corresponding to the digital signal. Delay applied to the data stream corresponding to the analog signal is increased at a rate that avoids audio artifacts of the output audio. The blend is performed when the data streams are aligned in time.
|LISTEN BEFORE TALK FREQUENCY AGILE RADIO SYNCHRONIZATION - A radio frequency communication system includes a transmitter that selects a frequency channel from among multiple frequency channels available to the transmitter and to a receiver, listens to ensure that a selected channel is unused before transmitting, and sends a preamble longer in time than a receiver scan time during which the receiver is operable to scan all frequency channels available to transmitter and receiver for the preamble. The receiver scans through the available frequency channels for a preamble, finds the preamble on a channel, and locks on to the channel on which the preamble was found.
|RECEIVING SYSTEM - A receiving system including a first apparatus and a second apparatus, the first apparatus and the second apparatus being connected through a transmission line, where the first apparatus includes an amplifier that amplifies a received signal, the signal amplified being transmitted to the second apparatus, a converting unit that reflects a pilot signal transmitted from the second apparatus through the transmission line and changes characteristics, and a control unit that controls the converting unit based on information obtained by monitoring the amplifier; and the second apparatus includes a pilot output unit that outputs the pilot signal, and a monitoring unit that monitors the first apparatus based on a level of a synthesized signal synthesized from the pilot signal output from the pilot output unit and a reflected signal that is from the first apparatus and includes the pilot signal reflected at the converting unit.
|COMMUNICATION APPARATUS, COMMUNICATION METHOD, COMMUNICATION PROGRAM, AND RECORDING MEDIUM - The present invention comprises a communication means
|Digital Transmitter - An equalizer provided in a digital transmitter compensates for attenuation in a signal channel to a digital receiver. The equalizer generates signal levels as a logical function of bit history to emphasize transition signal levels relative to repeated signal levels. The preferred equalizer includes an FIR transition filter using a look-up table. Parallel circuits including FIR filters and digital-to-analog converters provide a high speed equalizer with lower speed circuitry. The equalizer is particularly suited to in-cabinet and local area network transmissions where feedback circuitry facilitates adaptive training of the equalizer.
|SIGNAL RECEIVING DEVICE AND FREQUENCY DETERMINING CIRCUIT - A signal receiving device is adapted for receiving a multi-bit signal-under-test that supports one of first and second base frequency types, and outputting a type indicator for indicating which one of the first and second base frequency types is supported by the signal-under-test. The signal receiving device includes a counter and a frequency determining circuit. The counter includes an accumulating unit for counting cycles of an operating clock so as to obtain a bit count. The frequency determining circuit is coupled to the counter for comparing the bit count to one of first and second preset values in accordance with a previous value of the type indicator so as to obtain a comparison result, and determining whether to update a value of the type indicator based on the comparison result.
|RESOURCE USAGE CONTROL FOR REAL TIME VIDEO ENCODING - A video coding system and method that dynamically controls coding parameters to satisfy a resource usage requirement. A resource controller may set parameters or parameter thresholds to change the coding complexity of the video coding system and to effectuate a change in the resource usage rate. Parameters may include the frame rate, the frame resolution, the bit rate, or pixel block sizes. A parameter or parameter threshold adjustment may be based on system resource data, for example, power consumption, CPU usage, fan speed, battery status, input video statistics, coding latency, and other video encoder internal states.
|DISPARATE CLOCK DOMAIN SYNCHRONIZATION - Disparate clock domains are resynchronized after circuits in one of the clock domains awake from a reduced power state. Parallel test data is routed from a core circuit to a parallel-to-serial converter in an input/output (I/O) circuit. The parallel-to-serial converter clocks the parallel test data in response to a load signal. The load signal is varied until the clock domains are synchronized.
|TRANSMITTER APPARATUS, RECEIVER APPARATUS, COMMUNICATION SYSTEM, AND COMMUNICATION METHOD - A transmitter apparatus includes a reference signal transmitting unit that transmits a both of a first reference signal and a second reference signal differing from the first reference signal to a first receiver apparatus performing non-cooperative communication and to a second receiver apparatus performing cooperative communication, respectively. In addition, the transmitter apparatus includes a notifying unit that instructs the first receiver apparatus to measure the first reference signal and that instructs the second receiver apparatus to measure the second reference signal.
|SYSTEM AND METHOD FOR CHANNEL CLASSIFICATION - A system and method for classifying a channel with regard to delay spread in a wireless network applying orthogonal frequency division multiplexing. In one embodiment, a wireless receiver includes a channel classifier. The channel classifier is configured to compute a channel estimate corresponding to a channel traversed by a packet received by the wireless receiver. The channel classifier is also configured to partition the channel estimate into a plurality of windows. Each window corresponds to a range of time of the channel estimate. The channel classifier is further configured to assign a delay spread classification to the channel based on a distribution of energy across the windows.
|SIGNAL PROCESSING APPARATUS, SIGNAL PROCESSING METHOD, AND PROGRAM - A signal processing apparatus is disclosed which includes: a detection section configured such that based on a result of the error correction of a signal generated by a single carrier system, the detection section detects the presence or absence of spectrum inversion in the signal; and a selection section configured such that if the detection section detects the spectrum inversion, the selection section selects the spectrally inverted signal as the signal subject to the error correction, and that if the detection section does not detect the spectrum inversion, then the selection selects the spectrally uninverted signal as the signal subject to the error correction.
|Systems and Methods for Variable Thresholding in a Pattern Detector - Various embodiments of the present invention provide systems and methods for pattern identification. As an example, a pattern detection circuit is discussed that include: a distance calculation circuit operable to calculate a distance value corresponding to a difference between a first pattern and a second pattern; a threshold comparator circuit operable to compare the distance value to a variable threshold value; and a threshold value calculation circuit. The threshold value calculation circuit is operable to modify the variable threshold value based at least in part on the distance value.
|Method and Apparatus for Signal Peak-to-Average Ratio Reduction - A method and apparatus taught herein reduce the peak-to-average ratio (PAR) of a complex-valued signal based on detecting peaks in the signal that are above a peak threshold, characterizing the detected peaks in Cartesian coordinates, generating cancellation pulses in Cartesian coordinates based on the detected peak characterizations. PAR reduction processing continues with canceling the detected peaks by combining the cancellation pulses with a correspondingly delayed version of the signal. Advantageously, peak detection may be performed in polar form using a computationally efficient peak detection algorithm that avoids calculation of the I and Q peak waveforms unless a signal peak beyond a defined threshold is present. In one or more embodiments, the generation and use of asymmetric and/or shaped cancellation pulses offers further performance advantages.
|BEST FRAME DERIVATION IN A WIRLESS COMMUNICATIONS NETWORK - A communications node can receive a plurality of communication signals, each including a block of data estimates with respective quality metrics. Each block of data estimates can be derived from an original block of data sent over different wireless paths, or from a derived block of data estimates sent over a different wireless path. A data combining circuit can be used to combines the blocks of data estimates as a function of the respective quality metrics to produce an output set of data estimates with a derived quality metric.
|APPARATUS AND METHOD FOR MEASURING INDIVIDUAL RECEIVING POWER USING IDENTIFICATION SIGNAL - Provided is an apparatus and method for measuring an individual receiving power using an identification signal of a repeater or a transmitter. The apparatus and method includes a total receiving power measuring unit for measuring a total receiving power from transmitters; an identification signal analyzing unit for extracting a channel profile signal from the signal transmitted from the predetermined transmitter through a multi-path, wherein the predetermined transmitter transmits a signal having the identification signal; and an individual receiving power calculating unit for calculating an individual receiving power from the transmitter based on the measured total receiving power and the extracted channel profile signal.
|APPARATUS AND METHOD FOR DOWNCONVERTING RF MULTI-SIGNALS SIMULTANEOUSLY BY BANDPASS SAMPLING - The present invention relates to a method of down-converting RF multi-signals by bandpass sampling, which includes: setting up obtainable combinations of 2 spectrum signals extracted from 2N negative and positive spectrum signals existing for N RF signals; calculating available sampling ranges for the 2 spectrum signals in each obtainable combination; and determining an effective sampling range by the intersection of the available sampling ranges.
|SYSTEMS AND METHODS FOR DETERMINING A CHANNEL VARIATION METRIC - A method for determining a channel variation metric by an electronic device is described. The method includes receiving a first packet. The method also includes receiving a second packet. The method further includes determining a channel variation metric that approximates a mean square error value based on a first channel estimate corresponding to a first packet and a second channel estimate corresponding to a second packet. The method additionally includes performing an operation based on the channel variation metric.
|Interface Circuit and Method for Enabling an Output Driver of the Interface Circuit - An interface circuit includes an interface terminal, a voltage detection device, an output driver and an enable logic. The interface terminal is configured to connect to an interface line. The voltage detection device is configured to detect a voltage present at the interface terminal. The output driver is configured to apply an output signal to the interface terminal. The enable logic is configured to generate an enable signal for the output driver based on an evaluation signal output by the voltage detection device, wherein the enable signal affects an enabling of the output driver if the evaluation signal shows that the voltage present at the interface terminal meets a given condition.
|SAMPLING PHASE SELECTION METHOD FOR A STREAM OF DATA BITS - A sampling phase selection method for a data stream is provided, wherein the data stream has a variable data rate in a fixed time period. The method comprises generating a calibration signal, wherein the time interval of the calibration signal is longer than the fixed time period of the data stream, generating a first clock sequence and a subsequent second clock sequence, wherein the first and the second clock sequence are composed of a plurality of continuous clock phases and the number of the clock phases of the first clock sequence are the same as that of the clock phases of the second clock sequence, selecting one of the phases of the first and the second clock sequence, in turn, to provide a sampling phase, performing a plurality of samplings on the data stream to generate a flag signal, and selecting a final sampling phase according to the flag signals with different sampling phases.
|STORING DATA RELATING TO CABLES - A cable adapter apparatus (
|System and Method for Channel State Information Feedback in Wireless Communications Systems - A system and method for channel state information feedback in wireless communications systems are provided. A method for reporting channel information includes determining, at a user equipment, a channel information type for first channel information to be reported to a communications controller, determining the first channel information conditioned on previously reported channel information and on the channel information type, and reporting the first channel information, the channel information type, or a combination thereof, to the communications controller.
|Line Testing - Embodiments related to line testing are described and depicted. A digital subscriber line testing apparatus comprises a plurality of resistors and a switching device. The switching device comprises first and second signal inputs to couple the switching device to a signal generator output, and a plurality of wire terminals. The switching device is configured to switch the plurality of resistors into a first switching state and a second switching state.
|Transceiver system and associated methods and systems - In the example embodiments, test signals sent from a transmitting system are received at a receiving system. The receiving system generates a determination signal indicating, in one embodiment, whether received signals have a desired relationship with respect to a clock signal at the receiving system. Timing of the clock signal or timing for transmitting signals may be adjusted based on the determination. In another embodiment, the receiving system generates a determination signal indicating whether the pulse width of a lone pulse signal equals a desired time interval. Equalization or pre-emphasis is controlled based on the determination signal.
|METHOD AND APPARATUS FOR DETERMINING AN OUTAGE IN COMMUNICATION SYSTEMS - A method of detecting an outage includes determining at a source of data a quality metric of a link over which data is to be transmitted, modifying the quality metric by a quality metric margin, and declaring an outage event when power required for transmission of a reference signal exceeds power required for transmission of the reference signal determined form the modified quality metric. An apparatus for detecting an outage includes means for determining at a source of data a quality metric of a link over which data is to be transmitted, means for modifying the quality metric by a quality metric margin, means for determining a maximum rate of data in accordance with said modified quality metric, and means for declaring an outage event when power required for transmission of data at the maximum rate of data exceeds maximum allowable transmission power.
|CHANNEL INFORMATION FEEDBACK METHOD AND APPARATUS THEREOF - A channel information feedback method adapted in a receiving end of a multiuser multiple input multiple output (MU MIMO) system has following steps. A subspace matrix and a magnitude matrix related to a transmitting end of the MU MIMO system are obtained according to a channel matrix corresponding to the receiving end. A first quantization is performed on the subspace matrix to generate a quantized subspace matrix. A second quantization is performed on an auxiliary information matrix to generate a quantized auxiliary information matrix, where the auxiliary information matrix is corresponding to the magnitude matrix and a residual subspace matrix, and the residual subspace matrix includes residual subspace information after the first quantization is performed on the subspace matrix. The quantized subspace matrix and the quantized auxiliary information matrix are fed back to the transmitting end through an uplink channel.
|ESTIMATING BIT ERROR PROBABILITY (BEP) IN AN EDGE WIRELESS SYSTEM - Distribution parameter mapping determines the bit error probability (BEP) of a burst transmitted from a base station to the mobile station using a modulation and coding scheme (MCS) specified in the EDGE standard. Depending on whether the multi-bit soft decisions of the burst most resemble a Gaussian or a Rician distribution, the statistical parameters μ and σ or A and u are determined The ratio μ/σ or A/σ is mapped to an empirically determined BEP in a Gaussian or Rician lookup table, respectively. The BEPs are not influenced by the degree of code redundancy in the MCS. The BEPs for the four bursts in a radio block are then averaged, filtered and quantized according to the EDGE standard. The quantization level of the average BEP is reported to the base station so that subsequent radio blocks can be transmitted using an MCS that is appropriate for the estimated BEP.
|RADIOFREQUENCY TEST SYSTEM INTEGRATED IN A BASE STATION - The present invention provides a method of performing tests of at least one base station. The method includes accessing, using digital processing circuitry coupled to at least one base station, a portion of a radio frequency signal. The method also includes performing, using the digital processing circuitry, at least one measurement based upon the radiofrequency signal and providing information indicative of the measurements to a processing device at a location remote from the base station while the digital processing circuitry remains coupled to the base station(s).
|Method and Apparatus for Estimating Channel Length in Wired Communication System - A method for estimating a length of a channel in a wired communication system includes receiving a plurality of signals transmitted continuously via the channel, determining relation between a signal and at least one signal in the of the plurality of signals, to generate a decision result, and determining the length of the channel according to the decision result.
|HANDLING COMPLEX SIGNAL PARAMETERS - Apparatus, the apparatus having at least one processor and at least one memory having computer-readable code stored thereon which when executed controls the at least one processor to perform a method comprising: obtaining in-phase and quadrature samples of a received radio signal at least first and second discrete instances in time; processing the samples to provide information relating to the amplitude and/or phase of the received radio signal at the first and second instances in time; using the amplitude and/or phase information of the received radio signal at the first and second instances in time to determine whether interference is present on the received radio signal; forwarding the complex signal parameters for processing if interference is determined not to be present; and discarding the complex signal parameters without forwarding them for processing if interference is determined to be present.
|SELECTION OF ACQUISITION SEQUENCES FOR OPTIMAL FREQUENCY OFFSET ESTIMATION - Systems and methods are provided to generate a set of synchronization channel sequences that optimize time and frequency acquisition. A set of root indices of Zadoff-Chu sequences in a first domain (e.g., time domain) that optimize a performance metric or merit factor are identified. An optimal index is determined that also optimizes a performance metric in a reciprocal domain (e.g., frequency domain). Optimal indices satisfy a centro-symmetric relationship with respect to a half-value of sequence length: When 1 is an optimal index, N−1 is also an optimal root index. For sequences of length Q
|High Peak to Average Power Ratio (PAPR) Mitigation in High Speed Data Networks Using Symbol Mapping Adjustment - Embodiments provide techniques for high peak to average power ratio (PAPR) event mitigation in high speed data networks, such as cable networks, for example. Embodiments are applicable to multi-carrier and single-carrier modulation systems. Embodiments operate by predicting or detecting the occurrence of a peaking event at the transmitter, and then mitigating potential effects of the peaking event at the transmitter, including application of alternative constellation symbol mappings.
|SIGNAL PROCESSING APPARATUS, SIGNAL PROCESSING METHOD, AND PROGRAM - A signal processing apparatus configured to process a signal transmitted via a transmission path where a waveform represented by a signal value of a particular symbol is stationarily distorted in accordance with values of symbols transmitted prior to the particular symbol, including the following elements: a receiving unit configured to receive a test signal which is the signal including symbols set to predetermined values via the transmission path; an obtaining unit configured to obtain the signal value of the particular symbol from the test signal received by the receiving unit; and a characteristic computing unit configured to compute a characteristic of distortion of the waveform represented by the signal value of the particular symbol in accordance with the values of the symbols transmitted prior to the particular symbol on the basis of waveforms represented by signal values obtained by the obtaining unit from a plurality of test signals.
|METHODS AND APPARATUS TO QUALIFY A WIRE-PAIR FOR A DIGITAL SUBSCRIBER LINE (DSL) SERVICE - Methods and apparatus to qualify a wire-pair for a digital subscriber line (DSL) service are disclosed. An example method comprises modifying a digital subscriber line (DSL) signal received on a wire-pair at a DSL modem to emulate an environmental condition, and qualifying the wire-pair for a DSL service based on a DSL connection rate achieved by the DSL modem during the emulated environmental condition.
|DEVICE AND METHOD FOR CALIBRATING MIMO SYSTEMS - A device and method for calibrating MIMO systems are disclosed. In one aspect, a calibration circuit comprises at least a first and a second input/output port, each arranged for being connected to a different transmitter/receiver pair of a multiple input multiple output (MIMO) system. The circuit further comprises at least a third and a fourth input/output port, each arranged for being connected to a different antenna. The circuit further comprises an attenuator having a first attenuator port and a second attenuator port. The circuit further comprises a first and a second non-reciprocal switch, the first switch being arranged for establishing a connection between the first input/output port and either the third input/output port or the first attenuator port, and the second switch arranged for establishing a connection between the second input/output port and either the fourth input/output port or the second attenuator port.
|RADIO COMMUNICATION DEVICE - A radio communication device of the present invention comprises a first antenna, a second antenna, a phase varying section which varies a phase of a first RF signal received by or transmitted from the first antenna, and a phase control means which causes the phase varying section to vary a phase amount which is a varied amount of the phase of the first RF signal received by or transmitted from the first antenna. Thus, it is possible to prevent that a size of a device configuration increases and avoid that a reception electric field level is lowered in a localized area.
|ADAPTIVE CHANNEL TRACKING USING PEAK FADE DEPTH ESTIMATION OVER A SLOT - Peak fade depth is measured (
|RF I/Q Modulator with Sampling Calibration System - A vector RF modulation system includes a sampling receiver that monitors modulator RF output and provides IF signals for a processor that calculates modulator calibration parameters.
|Method and device for interception of data transiting on a link in an Ethernet network - The invention relates to a method and device for real time interception of data transported on several links in an Ethernet network. With this method:
|SIGNAL ANALYZER AND METHOD FOR DISPLAYING FREQUENCY DOMAIN DATA - A signal analyzer provides frequency domain data at different time and frequency resolution. First type frequency domain data is derived from time domain data of a signal under test by first type frames and displayed as a spectrogram. A selecting box is displayed on the spectrogram for selecting the first type frames. The signal analyzer produces second type frequency domain data by treating the time domain data corresponding to the first type frequency domain data included in the selected first type frames with the selecting box as one frame by FFT calculation. The resultant second type frequency domain data are displayed as a spectrum that has different time and frequency resolution from the spectrogram.
|Real Time Dynamic Correlator for Evaluating Electrical Characteristics of a Transmitter - Systems and methods for evaluating electrical characteristics of a transmitter in real time are provided. A particular system includes a code generator configured to generate reference code and test code. The reference code and test code both include a plurality of frames of data. The code generator is further configured to output the reference code at a first rate and to output the test code at a second rate that is different than the first rate. The system also includes a modulator configured to modulate the reference code into a first modulated code. The system further includes a correlator configured to correlate the first modulated code with test code that has been modulated and transmitted by a transmitter as a second modulated code.
|VEHICULAR POWER LINE COMMUNICATION SYSTEM - A vehicular power line communication system includes a master and a slave. The master uses a pair of twisted wires, whose far ends are connected to each other to be loop-shaped, as a power line and a communication line. The master thereby outputs high-frequency signals via the pair of twisted wires, transmitting an electric power and data modulation signals. The slave includes an aperture antenna being loop-shaped to receive data modulation signals using an electromagnetic induction connection in an electromagnetic field generated in the pair of twisted wires in response to an energization current of the pair of twisted wires. The slave further includes an error rate monitor circuit which monitors an error rate of data which are obtained from demodulation of the data modulation signals received via the aperture antenna.
|Method and System for Determining a Quality Value of a Video Stream - Hence a method is provided for determining a quality value of a video stream, comprising the steps of: identifying lost data packets of the video stream; identifying at least two intra coded frames of the video stream; determining intra coded frames having a maintained image quality, based on estimating if a lost data packet is associated with an intra coded frame; estimating a distance between each one of the lost data packets and a next respective, subsequent intra coded frame having a maintained image quality; and generating the quality value, based on the distances. A system and a computer readable medium are also described.
|MOBILE COMMUNICATION METHOD, MOBILE COMMUNICATION SYSTEM, AND RADIO BASE STATION - A mobile communication method includes: a step in which a neighboring radio base station eNB#A stops transmission of signals other than a predetermined signal in a predetermined subframe within a predetermined frequency band; a step in which a measurement target radio base station eNB#B changes the transmission frequency or the transmission timing of a pilot symbol not to overlap with the transmission frequency and the transmission timing of the predetermined signal; and a step in which a mobile station UE measures the reception quality of the pilot symbol transmitted by the measurement target radio base station eNB#B.
|Transmitting Device, Receiving Device, Circuit Device, Communication Method and Program - A transmitting device, a receiving device, a circuit device, and a communication method to reduce problems due to coupling present between the transmitting device and the receiving device. The transmitting device including: a model storage unit for storing a change model for a reference level of a signal on the receiving device end due to coupling between the transmitting device and a receiving device; a compensation calculating unit for calculating a compensation value for offsetting a change in the reference level of the signal constituting a symbol sequence; and an output waveform changing unit for changing an output waveform of the signal constituting the symbol sequence on the basis of the compensation value for the change in the reference level.
|METHOD AND DEVICE FOR CHANNEL RESPONSE DETERMINATION - A method and a device for channel response determination for a wireless communication system. The method comprises generating a first vector of channel responses from channel estimations obtained by using a training signal. A second vector of regularized channel responses is generated by applying to the first vector a regularization algorithm. The algorithm is operative such that a second difference between consecutive regularized channel responses of the second vector is less than a first difference between consecutive channel responses of the first vector.
|CONTROLLING APPARATUS AND CONTROLLING METHOD OF A WIRELESS DEVICE, AND BASE STATION APPARATUS - A controlling apparatus installed in a base station with a plurality of wireless devices, for controlling operations of the plurality of wireless devices. The controlling apparatus includes an interface device for transmitting and receiving data with at least one of the plurality of wireless devices according to timing provided by an internal clock, a measurement device for measuring the delay times corresponding to the transmission and the reception of the data between the interface device and the plurality of wireless devices, and a correction device for correcting a difference of the delay times corresponding to the plurality of wireless devices by changing the internal clock.
|Signaling with Superimposed Clock and Data Signals - A data transmission circuit includes a clock driver to obtain a clock signal having a first rate and to drive the clock signal onto one or more transmission lines. The data transmission circuit also includes a timing circuit to obtain the clock signal and to generate a symbol clock having a second rate. The first rate is a multiple of the second rate, wherein the multiple is greater than one. The data transmission circuit further includes a data driver synchronized to the symbol clock. The data driver obtains a data signal and drives the data signal onto the one or more transmission lines at the second rate. The data signal and the clock signal are driven onto the one or more transmission lines simultaneously.
|METHOD AND APPARATUS FOR MEASURING BIT ERROR RATE OF TUNER - A test signal generator
|PACKET-FILTER-USED CLOCK SYNCHRONIZATION SYSTEM, APPARATUS, METHOD AND PROGRAM THEREOF - A clock synchronization system synchronizes a clock of a slave node with a clock of a master node. The master node includes a packet transmitting unit that transmits a packet including a time stamp (TS) to the slave node. The slave node includes: a packet receiving unit that receives the packet transmitted from the master node; a packet filter unit that calculates as a value of delay of the packet a difference between a TS on the clock of the slave node when the packet is received and the TS of the packet received, corrects the value of the delay of the packet or a threthold for the delay of the packet, and performs filter processing on the packet received from the packet receiving unit based on the value of the delay of the packet and the threshold for the delay of the packet; and a phase synchronization unit that outputs the clock of the slave node based on the TS included in the packet employed.
|WIRELESS COMMUNICATION APPARATUS, SIGNAL PROCESSING METHOD, AND NON-TRANSITORY COMPUTER READABLE MEDIUM - A wireless communication apparatus receives a signal with a no signal section inserted between OFDM symbols and includes an overlap addition number table unit and an overlap addition unit. The overlap addition number table unit associates band information specifying a frequency band to transmit a signal and an overlap addition number specifying a number of samples in the no-signal section to be overlap-added to an OFDM symbol. The overlap addition unit adds data to a beginning of the OFDM symbol using the overlap addition number table, the data corresponding to the overlap addition number determined according to the band information.
|METHOD FOR THE ESTIMATION OF OFDM PARAMETERS BY ADAPTATION OF COVARIANCE - This invention relates to a method for the blind or semi-blind estimation of at least one modulation parameter of an OFDM signal utilising a method for adapting the covariance. According to this method, a plurality of values of this parameter are tested by calculating, for each of these values, a distance between a covariance matrix of vectors composed of samples of the signal and a theoretical covariance matrix. The estimated value of the parameter is the tested value which achieves the shortest distance. Said method provides a very good rate of good estimates, even when the OFDM prefix is short or absent. Furthermore, it makes it possible to obtain a joint estimation of several time parameters and, where applicable, of the signal-to-noise ratio.
|Generating test sequences for circuit channels exhibiting duty-cycle distortion - Disclosed herein are exemplary methods, apparatus, and systems for generating test sequences that can be used to evaluate high-speed circuit pathways that exhibit duty-cycle distortion (e.g., clock-related duty-cycle distortion or data-dependent duty-cycle distortion). In one exemplary embodiment, a period of an input signal is divided into two or more subintervals, each subinterval having a duration that is different from other subintervals. Pulse representations are generated for each of the subintervals, the pulse representations representing pulse durations corresponding to the respective durations of each of the subintervals. Inverted sampled pulse responses are generated to the pulse representations. Samples from two or more of the inverted sampled pulse responses are combined to create one or more combined inverted sampled pulse responses. A test sequence is determined for testing the electrical behavior of a circuit channel using the one or more combined sampled pulse responses and stored on one or more computer-readable media.
|Feedback System and Apparatus for Video Compensation - A system and apparatus for compensating cable losses in a video signal transmission system includes feedback circuits to determine the spectral attenuation of a received signal and to control an equalizer circuit to amplify selected frequencies of the received signal, and to determine the various times of arrival of two or more video signals and selectively adjust one or more delay lines to reduce the differences in their arrival times.
|RECEIVING CIRCUIT, METHOD FOR RECEIVING A SIGNAL, AND USE OF A DETECTION CIRCUIT AND A CONTROL CIRCUIT - A receiving circuit, method for receiving a signal, and use of a detection circuit and a control circuit of a receiving circuit of a node of a radio network is provided to deactivate an analog signal processing and/or determination of digital data from a signal received over an antenna of the node, when a stored current frame of the digital data has been recognized as valid, and to activate the analog signal processing and/or the determination, when the transmission of the current frame over an interface of the control circuit has been confirmed, whereby the control circuit is connected to the detection circuit and/or an input circuit for deactivation and activation, and whereby the detection circuit is formed to determine the digital data from the received signal.
|METHOD, APPARATUS, AND SYSTEM FOR TIME SYNCHRONIZATION OF XDSL - The present invention provides a method, an apparatus, and a system for time synchronization of an xDSL. The method includes: transmitting, by a customer premises equipment, a first symbol to a central office equipment, and obtaining time Ts
|EXPLOITING MULTIPLE ANTENNAS FOR SPECTRUM SENSING IN COGNITIVE RADIO NETWORKS - Spectrum sensing in wireless communications is provided to identify utilized and/or unutilized frequency bands reserved for primary users using a cyclostationary beamforming approach. An adaptive cross self-coherent restoral (ACS) algorithm can be utilized to extract signals of interest (SOI) at unique cycle frequencies related to primary and/or secondary users from an antenna array measurement. Based on the SOI, one or more users of the spectrum can be identified or the spectrum can be regarded as vacant; this can be based on lobe identification in the frequency spectrum of the SOI, in one example. This mechanism is less complex than traditional cyclic spectrum analysis methods. The cyclostationary beamforming based approach is more effective than the energy detection method. Also, the need for quiet periods in spectrum sensing is eliminated when using this mechanism such that signals can be transmitted simultaneously with receiving signals over the antenna array.
|IDENTIFICATION OF BOARD CONNECTIONS FOR DIFFERENTIAL RECEIVERS - Embodiments of the invention include testing arrangements for detecting proper DC-coupled board connections on the input legs of a differential receiver. The testing implementation includes a first test receiver AC-coupled to the connection between the first input/output (I/O) pad and the differential receiver positive input and/or a second test receiver coupled to the connection between the second I/O pad and the differential receiver negative input. The test receiver protects the test receiver input from DC voltages applied to the differential receiver via the differential receiver input. Also, the test receiver includes a high-pass filter arrangement that generates data capable of detecting whether the I/O pad connected to the test receiver has a proper DC-coupled connection or an improper connection when presented with a stimulus pulse. The test receiver is less susceptible to noise because than conventional arrangements that use a low-pass RC filter.
|DEVICE, SYSTEM AND METHOD FOR MEASURING SIGNALS - A system for measuring signals includes: a simulating device, adapted to simulate equalization for an incoming signal of an SERDES receiving chip and generate a response signal, and a feature output device, adapted to output the feature information of the response signal. The invention also discloses a method and a device for measuring signals.
|TEST UNIT FOR TESTING THE FREQUENCY CHARACTERISTIC OF A TRANSMITTER - A test unit for testing the frequency characteristics of one or more components of a transmitter of modulated signals. The test unit includes a data source for generating a test pattern of data. A test unit output is connected to the data source and connectable to an input of one or more of the components, for inputting the test pattern of data to the one or more components. The test unit includes a memory in which a first predetermined data sequence and a second predetermined data sequence are stored. The data source is connected with an data input to the memory, and the data source is arranged to generating the test pattern of data including the predetermined data sequences. When a modulated signal is generated in accordance with the test pattern of data will include a first signal part with a first frequency spectrum caused by the first predetermined data sequence and a second signal part after the first signal part, which second signal part has a second frequency spectrum caused by the second predetermined data sequence.
|Modal PAM2/PAM4 Divide By N (Div-N) Automatic Correlation Engine (ACE) For A Receiver - A correlation engine includes a first register configured to receive a test data signal, a second register configured to receive a main data signal, first shift logic configured to shift the test data signal by a predetermined value between 0 and 3 symbols, second shift logic configured to shift the main data signal by a predetermined value between 0 and 20 symbols, and comparison logic configured to compare the shifted test data signal and the shifted main data signal to generate an error signal.
|METHOD AND APPARATUS FOR INTEGRAL STATE INITIALIZATION AND QUALITY OF LOCK MONITORING IN A CLOCK AND DATA RECOVERY SYSTEM - Methods and apparatus are provided for improving the performance of second order CDR systems. The integral state of the CDR system is initialized to a value that is based on an expected frequency profile that may be known a priori for certain applications. One or more quality of lock (QOL) metrics are also monitored that are derived from the integral register state value. A quality of a locking between a received signal and a local clock generated by a Clock and Data Recovery (CDR) system is evaluated by monitoring a state value of an integral register in a digital loop filter of the CDR system; evaluating one or more predefined criteria based on the integral register state value; and identifying a poor lock condition if the one or more predefined criteria are not satisfied.
|SYSTEM AND METHOD OF FREQUENCY OFFSET COMPENSATION FOR RADIO SYSTEM WITH FAST DOPPLER SHIFT - A system and method of frequency offset compensation are disclosed for a wireless system between a fast moving radio terminal associated with a locomotive and a stationary radio terminal associated with a base station. The present invention utilizes advanced frequency offset prediction to quickly track Doppler Shift caused by a fast moving locomotive. In one embodiment according to the present invention, the frequency offset prediction is based on a first plurality of coarse frequency offsets, first-order derivatives of the first plurality of coarse frequency offsets, and second-order derivatives of the first plurality of coarse frequency offsets. In another embodiment according to the present invention, the frequency offset prediction is based on a plurality of previous frequency offsets according to a Doppler shift model.
|TEST APPARATUS AND PROGRAM - Provided is a measurement apparatus that measures power of an orthogonal frequency division multiplexing modulated signal (OFDM modulated signal) output from a transmitting device, comprising an output control section that causes the transmitting device to output the OFDM modulated signal having a prescribed waveform that repeats in each of a plurality of repetition periods; and a power measuring section that measures, over a measurement period that corresponds to an integer multiple of the repetition period, the power of the OFDM modulated signal output by the transmitting device. The output control section may cause the transmitting device to output the OFDM modulated signal having, as the repetition period, a period for which the arrangement of a pilot signal is the same in a direction of sub-carriers and a direction of OFDM symbols.
|COMPLEX ADAPTIVE PHASE ESTIMATION - A Complex Adaptive Phase Estimation (PE) filter, as presented in some concepts of the present disclosure, is an adaptive filter that accurately estimates the phase difference between signals. For example, the PE filter can estimate the phase difference between a complex primary signal and a complex incident signal, iteratively adapting the phase of a complex exponential by minimizing the mean squared error of a complex error signal. The PE filter can demonstrate accurate phase estimation and rapid convergence, with low computational complexity and storage requirements. In addition, the PE filter construction can be simplified to support absolute phase estimation of a single complex signal. Efficient complex normalization approximation can be developed to support practical PE filter implementation in computationally restrictive environments, including systems with real-time response constraints, and systems without efficient native or functional support for division or square root operations.
|CHANNEL ESTIMATING METHOD AND DEVICE - A channel estimating method and device are provided. The method includes: performing multi-path searching on a pilot channel, and performing interpolation on a channel estimation value at a radial position of the multi-path searching (
|TMDS RECEIVER SYSTEM AND BIST METHOD THEREOF - A transition minimized differential signaling (TMDS) receiver system including a clock channel, a plurality of data channels, a TMDS decoding unit, and a self-test unit is provided. The clock channel receives, processes and outputs a clock signal. Each data channel receives, processes and outputs a corresponding data signal according to the clock signal. The TMDS decoding unit receives and decodes the processed data signals. The self-test unit receives the clock signal and an external parallel signal, and accordingly, generates a test signal for performing the BIST on the data channels and the TMDS decoding unit. A BIST method adapted for the TMDS receiver system is also provided.
|HYBRID POWER LINE/WIRELESS APPLIANCE AUTOMATION SYSTEM, DEVICE, AND POWER MONITORING METHOD UTILZING THE SAME - The present invention discloses a hybrid power line/wireless appliance automation system for interfacing between at least one electric power distribution circuit and at least one electronic device, a power line communication device, and a power monitoring method using the same. Each power line communication device can be communicatively interconnected via power line communication and/or wireless communication. A threshold value of each power line communication device is dynamically adjusted by a host device via wired or wireless connection, so as to determine whether to continuously supply or turn off power to an electronic device coupled to the power line communication device. The present invention may be implemented/integrated to existing household electric power network without the need for additional physical data network infrastructure/lines, therefore is suitable to be applied in an intelligent home management system.
|Wireless Distance Measurement System and Wireless Terminal - A wireless distance measurement system and wireless terminal improve the accuracy of distance measurement when the UWB communication scheme is used. In wireless terminal
|WIRELESS TRANSMISSION SYSTEM, AND METHOD FOR DETERMINING DEFAULT GAIN OF WIRELESS TRANSMISSION SYSTEM - A method for determining a default gain of a wireless transmission system is provided. The wireless transmission system includes a signal transmission path and a signal feedback path coupled to the signal transmission path. The signal transmission path includes a power amplification circuit and a gain stage having a plurality of transmission gains. The method includes the following step: setting a gain of the gain stage as a specific transmission gain of the transmission gains; transmitting a plurality of test signals through the signal transmission path in sequence to generate a plurality of amplified test signals, wherein at least a portion of powers of the test signals correspond to the transmission gains, respectively; receiving the amplified test signals through the signal feedback path in sequence, and accordingly obtaining corresponding signal gains; and determining a default gain of the gain stage according to the signal gains.
|PORTABLE APPARATUS AND METHOD OF MEASURING WIRELESS CHANNEL AND MULTIPLE ANTENNA CORRELATION - A portable apparatus of measuring a wireless channel and a multiple antenna correlation, the apparatus including: a Radio Frequency (RF) unit to control a frequency of a signal to be measured, to broadcast the signal to be measured through multiple transmission antennas, to control a frequency of a received signal, and to send the received signal to the baseband unit, the received signal being received through multiple receiving antennas; and a baseband unit to generate and transmit, to the RF unit, the signal to be measured, to measure wireless channels for each of the multiple transmission antennas and wireless channels for each of the multiple receiving antennas based on the received signal output from the RF unit, to calculate a correlation for each of the multiple transmission antennas, and to calculate a correlation for each of the multiple receiving antennas based on the wireless channels for each of the multiple transmission and receiving antennas.
|SIGNAL PROCESSING FOR DIVERSITY COMBINING RADIO RECEIVER - A signal processing device for a diversity combining radio receiver is disclosed. Said device comprises a plurality of receive branches and a joint detector adapted to determine a joint received symbol based on a combined signal. Said device also comprises a control unit adapted to determine a branch signal error based on the joint received symbol and the input signal of that receive branch. Each receive branch further comprises an adaptive filter. The control unit is adapted to update the coefficients of the adaptive filter of each receive branch based on a weighted signal error combination, wherein weight of the weighted signal error combination is selected based on channel conditions. A corresponding diversity combining radio receiver, a corresponding electronic apparatus, a corresponding method, a corresponding computer program product, and a corresponding computer readable medium are also disclosed.
|SELF-TESTING INTEGRATED CIRCUITS - In an example, a self-testing integrated circuit (IC) includes N channels i and a controller, where i is an integer from 1 to N. Each channel i may include a clock and data recovery circuit (CDR), a pseudorandom bit stream (PRBS) generator circuit, and a PRBS checker and eye quality monitor (EQM) circuit. The controller may be configured to selectively couple the channels i in a daisy chain during self-testing.
|TEST APPARATUS FOR 64B/66B ENCODING PROCESS - The present invention provides a test apparatus for a
|SIGNAL QUALITY MEASURING APPARATUS AND METHOD THEREOF - A signal quality measuring apparatus includes a binary signal generating unit to generate a binary signal from an input signal; a level information extracting unit to extract level information from a relationship between the input signal and the binary signal using at least two window lengths; and a quality calculating unit to calculate a quality of the input signal based on the level information.
|SYSTEM AND METHOD FOR DETERMINING THE ENVELOPE OF A MODULATED SIGNAL - Systems and methods for determining the envelope of a modulated signal using high bandwidth and low bandwidth samples of a hybrid signal. The hybrid signal is obtained by mixing the modulated signal with its carrier signal. The systems and methods of the present disclosure may be suitable for equivalent-time or real-time oscilloscopes.
|SYSTEMS AND METHODS FOR MEASURING I-Q MISMATCH - An exemplary embodiment of the present invention provides a method of measuring I-Q mismatch in a system having a transmitter. The transmitter comprises an in-phase up-converter, a quadrature-phase up-converter, and a power detector. The method of measuring I-Q mismatch comprises measuring an in-phase transmit power at the power detector caused by transmitting an in-phase output signal to the in-phase up-converter, measuring a quadrature-phase transmit power at the power detector caused by transmitting a quadrature-phase output signal to the quadrature-phase up-converter, calculating a transmitter-gain-mismatch as a function of the in-phase transmit power and the quadrature-phase transmit power, measuring an I-Q transmit power at the power detector caused by simultaneously transmitting a gain-mismatch-compensated in-phase output signal to the in-phase up-converter and a gain-mismatch-compensated quadrature-phase output signal to the quadrature-phase up-converter, and calculating a transmitter-phase-mismatch as a function of the I-Q transmit power.
|SIGNAL TRANSMISSION APPARATUS AND METHOD - According to an aspect of the embodiment, a signal transmission apparatus includes a sine wave output unit that outputs a sine wave to a transmission path, network analyzers and that analyze signals on the transmission path, an S parameter measurement unit that measures S parameters based on the analysis, a selection unit that selects a plurality of combinations of an amplitude, an emphasis characteristic, and an equalization characteristic based on the S parameters, measurement units that measure a BER or an eye opening of the transmission path for the plurality of combinations, and a setting unit that extracts single combination based on the measurement and that sets the amplitude, the emphasis characteristic, and the equalization characteristic to a transmission unit and a reception unit.
|APPARATUS AND METHOD FOR ADAPTIVELY ESTIMATING CHANNEL IN ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING (OFDM) SYSTEM - An apparatus and a method are provided including a parameter estimator, a controller, an initial channel estimator, and a channel estimator. The parameter estimator configured to estimate parameters related to a channel. The controller configured to select one of channel environments based on the parameters, and generate a control signal corresponding to the selected channel environment. The initial channel estimator configured to estimate an initial channel based on the control signal. The channel estimator configured to estimate a channel of remaining resource blocks, excluding resource blocks corresponding to a pilot signal, from among resource blocks, based on the initial channel and the control signal.
|SCALING APPARATUS OF A RECEIVER - A scaling apparatus set in a receiver is disclosed. The receiver includes a symbol-processing unit. The scaling apparatus includes a calculating unit and a scaling unit. The calculating unit estimates the signal strength of an input symbol and generates a scaling factor accordingly. The scaling unit scales an output symbol outputted from the symbol-processing unit according to the scaling factor. The output symbol is generated from the symbol-processing unit through processing the input symbol.
|METHOD FOR CHANNEL STATE FEEDBACK BY QUANTIZATION OF TIME-DOMAIN COEFFICIENTS - The present invention relates to a channel state transmission method using time domain coefficient quantization. A terminal measures channel information in the time domain and transmits it to a base station. In this instance, a multipath frequency selective fading channel is displayed in a tapped delay line format configured with a per-path path delay value and a path gain in the time domain, differentiates a quantization level for each path gain for more efficient transmission, quantizes the same, and transmits it to a transmitter. Therefore, while the amount of bandwidths required for transmitting state information from the terminal to the base station is reduced, the base station can efficiently acquire channel state information on the entire bandwidths. Also, the base station transmits signals to many terminals through beamforming by using the acquired reliable channel state information, thereby increasing the terminal's signal receiving performance.
|CHANNEL-ASSISTED ITERATIVE PRECODER SELECTION - As a basis for precoder quantization, a channel matrix representing multi-antenna channel characteristics between a transmitter and a receiver in the mobile communications network is estimated (S
|COMMUNICATION UNIT WITH ANALOG TEST UNIT - Various devices and techniques for testing an analog portion of communication devices are disclosed. Such devices may include a communication unit and an analog test unit. The analog test unit may be configured to test analog portions of the communication unit and communicate information regarding testing to an external test unit. The analog test unit may also be configured to perform an analysis of a test signal that is output by a transmitter portion, looped back to a receiver portion, and subsequently received by the analog test unit. The analog test unit may also be configured to calibrate a DC offset of a receiver chain of the communication unit. The analog test unit may also be configured to perform a nonlinearity test on one or more ADCs and/or DACs of the communication unit.
|METHOD, DEVICE AND SYSTEM FOR DETECTING CHANNEL QUALITY - A method, a device and a system for detecting channel quality are provided. The method includes: judging whether a Transmit Power Control (TPC) symbol output by a receiver is an invalid symbol; when the TPC symbol is a valid symbol, judging whether polarities of in-phase/quadrature (I/Q) components of the valid symbol are opposite to each other; counting the number of invalid symbols, the number of valid symbols, and the number of valid symbols with opposite polarities; and estimating a Bit Error Rate (BER) according to the number of the invalid symbols, the number of the valid symbols, and the number of the valid symbols with the opposite polarities, and detecting the channel quality through the BER.
|METHODS AND APPARATUS FOR PSEUDO ASYNCHRONOUS TESTING OF RECEIVE PATH IN SERIALIZER/DESERIALIZER DEVICES - Methods and apparatus are provided for pseudo asynchronous testing of receive paths in serializer/deserializer (SerDes) devices. A SerDes device is tested by applying a source of serial data to a receive path of the SerDes device during a test mode. The receive path substantially aligns to incoming data using a bit clock. A phase is adjusted during the test mode of the bit clock relative to the source of serial data to evaluate the SerDes device. The source of serial data may be, for example, a reference clock used by a phase locked loop to generate the bit clock. The phase of the bit clock can be directly controlled during the test mode, for example, by a test phase control signal, such as a plurality of interpolation codes that are applied to an interpolator that alters a phase of the bit clock.
|METHOD AND APPARATUS FOR MEASURING TIME DELAY IN ENVELOPE ELIMINATION AND RESTORATION TRANSMITTER - Provided are a method and apparatus for measuring a time delay in an envelope elimination and restoration (EER) transmitter. A method of measuring a time delay in an EER transmitter includes receiving a modulated sinusoidal signal and distributing the modulated sinusoidal signal to be transmitted through transmission lines separated from each other, extracting an amplitude modulation signal and a phase modulation signal from the modulated sinusoidal signal, and detecting envelops of the amplitude and phase modulation signals and determining a difference in time between the amplitude and phase modulation signals. In the EER transmitter, to measure a time delay between input and output signals, time delays of paths of amplitude and phase modulation signals of the input signal are compared, thereby determining a difference in time between the amplitude and phase modulation signals.
|COORDINATED MULTI-POINT TRANSMISSION USING INTERFERENCE FEEDBACK - Embodiments of methods and apparatus for wirelessly receiving, by a user equipment (UE), interference signal from a first enhanced Node B (eNB) while the UE is communicating with a second eNB; generating interference feedback information that is associated with an interference channel between the first eNB and the UE; and transmitting the interference feedback information to the first eNB via the second eNB are disclosed. Additional variants and embodiments are also disclosed.
|TRANSMISSION CIRCUIT, DIFFERENTIAL SIGNAL TRANSMISSION CIRCUIT, AND TEST APPARATUS - Provided is a test apparatus, a differential signal transmission circuit, and a transmission circuit that transmits signals between an input terminal and an output terminal, comprising a first high frequency signal passing section that blocks a low frequency signal that has a frequency less than a predetermined reference frequency in a signal received from the input terminal, and transmits a high frequency signal that has a frequency greater than or equal to the predetermined reference frequency to the output terminal; an input-side low frequency signal passing section that passes the low frequency signal in the signal from the input terminal and attenuates the high frequency signal; an output-side low frequency signal passing section that transmits to the output terminal the low frequency signal passed by the input-side low frequency signal passing section and attenuates the high frequency signal from the first high frequency signal passing section; and a switching section that switches a connection between the input-side low frequency signal passing section and the output-side low frequency signal passing section.
|Method and System for Measuring the Occupation and Allocation of a Transmission Spectrum - The invention relates to a method for measuring the occupancy of at least one transmission spectrum for a multicarrier radiofrequency signal communication system, wherein the method comprises slicing the spectrum into subsets of carriers and of time slicing within the subsets to form elementary time/frequency segments, signal non-transmission, by at least one transmission equipment item of the system, during elementary non-transmission segments mutually shifted over time and in frequency, and measuring chosen parameters of signals conveyed in the transmission spectrum during each of these elementary non-transmission segments.
|Method and Device for Transmitter Calibration - A device for calibrating a digital communication station uses an initial ranging procedure for measuring channel parameters in a communication channel. The device comprises a communication emulator, a measuring device, and a calibrator. The communication emulator transmits a signal to the communication station which transfers the communication station into an initial ranging mode. The measuring device measures parameters of the signal transmitted by the communication station during an initial ranging cycle. From these measurements the calibrator calculates the necessary calibration adjustments to the communication station and adjusts it accordingly.
|RECEIVING APPARATUS AND RECEIVING METHOD - A receiving apparatus receives a digital modulation signal. The receiving apparatus has a receiving part for down-converting the digital modulation signal to a baseband signal and to obtain channel estimates, a channel estimation part for estimating a multi-path channel, a first replica generation part for generating a first replica, based on the channel estimates obtained by the channel estimation part, a first replica removal part for removing the first replica from a target frame in the baseband signal, a nulling part for forcefully nulling he baseband signal for at least a portion of the time period where an inter-frame interference occurs due to a delay wave having a delay time longer than the known signal, and a cyclic-addition part for performing cyclic-addition between a front side portion and a rear side portion in the target frame, including the portion nulled by the nulling part.
|Method and Device for Checking a Subscriber Line - In a method for checking a subscriber line with a first and a second electrical line, wherein each line is connected to an encoder/decoder via a subscriber line circuit, the first line is connected to ground, a resistance of the second line is increased, an audio signal is outputted from the encoder/decoder to the first line; and a first frequency-selective signal is measured at a point at which the encoder/decoder is connected to the first line. Further, the second line is connected to ground, a resistance of the first line is increased, a further audio signal is output from the encoder/decoder to the second line, and a second frequency-selective signal is measured at a point at which the encoder/decoder is connected to the second line. An amplitude difference between the first and second frequency-selective signals is ascertained.
|System and Method for Processing Secure Transmissions - A method and apparatus for improving channel estimation within an OFDM communication system. Channel estimation in OFDM is usually performed with the aid of pilot symbols. The pilot symbols are typically spaced in time and frequency. The set of frequencies and times at which pilot symbols are inserted is referred to as a pilot pattern. In some cases, the pilot pattern is a diagonal-shaped lattice, either regular or irregular. The method first interpolates in the direction of larger coherence (time or frequency). Using these measurements, the density of pilot symbols in the direction of faster change will be increased thereby improving channel estimation without increasing overhead. As such, the results of the first interpolating step can then be used to assist the interpolation in the dimension of smaller coherence (time or frequency).
|POWER LINE COMMUNICATION METHODS AND DEVICES - A power line communication method for realizing data communication between at least one first or sending power line communication partner device and at least one second or receiving power line communication partner device. The method checks transmission conditions of a plurality of possible communication channels, thereby generating transmission condition data descriptive for the communication conditions of the respective possible communication channels. Additionally, communication conditions of the plurality of possible communication channels are selected as actual communication conditions based on the transmission condition data.
|METHOD AND APPARATUS FOR MEASURING AND CORRECTING RECEIVER PARAMETERS - A method and apparatus for measuring parameters of a receiver having a mixer for generating an I signal and a Q signal using an input signal, an I channel circuit for processing the I signal, and a Q channel circuit for processing the Q signal. The method includes feeding the receiver a first testing signal before the mixer. The method includes feeding the receiver a second testing signal on the I channel circuit. The method includes feeding the receiver a third testing signal on the Q channel circuit. The method includes measuring I/Q quadrature deviation and I/Q delay imbalance of the receiver using the first, the second, and the third testing signals. This separates the I/Q quadrature deviation and I/Q delay imbalance.
|System And Method For Adjusting A Serial Communications Link - A system for adjusting a serial communications link includes a system under test including at least one transmitter and at least one receiver coupled together via a serial data communications link, wherein at least one of the transmitter and the receiver has at least one tunable parameter, at least one controller coupled to at least one of a transmitter and a receiver via a joint test action group JTAG interface, and logic configured to adjust the at least one tunable parameter to optimize a performance of the serial data communications link.
|METHODS FOR ANALYZING AND OPTIMIZING THE PERFORMANCE OF A DATA COLLECTION NETWORK ON AN ELECTRICAL DISTRIBUTION GRID - A system and methods for optimizing the performance of communication network utilizing an electrical distribution grid are disclosed. Optimization methods may include archiving historical message data and metrics from transmissions by Remote Hubs received on one or more Substation-to-Edge channels. Trends in the archived metrics over time are later analyzed to determine which combination of transmission variables such as frequency band, modulation method, drive voltage, and transmission time produce the highest message success rates overall. The results of such analysis may be used to provide feedback to the Remote Hubs or reveal necessary repairs to the network. Optimization may also be carried out locally by an individual Remote Hub by estimating the impedance of the transmission medium and adjusting either drive voltage or transmission band.
|METHOD OF CHARACTERIZING IMPAIRMENTS DETECTED BY EQUALIZATION ON A CHANNEL OF A NETWORK - An automated method of characterizing distortion detected by equalization on a channel of a network is provided. Equalization stress of an observed channel equalization response of an end device of the network is estimated, and equalization stress is calculated for a theoretical channel equalization response of the end device mathematically based on the observed channel equalization response and a theoretical removal of a suspected impairment from the network. The above referenced calculating step is separately repeated for each of a plurality of suspected impairments stored in a database of suspected impairments. A highest ranking suspected dominant impairment is determined from the database of suspected impairments such that removal of the highest ranking suspected dominant impairment from the network would provide a greatest reduction of equalization stress of a channel equalization response of the end device.
|OFDM COMMUNICATION WITH MULTI-DIMENSIONAL RATE ADAPTATION - A method for performing rate adaptation of millimeter wave transmissions in a substantially line-of-sight OFDM outdoor system over a radio frequency (RF) channel includes the following. First a channel quality estimator indicative of a quality of an outdoor millimeter-wave RF channel is received. A sequence of parameter changes is defined to dynamically adjust transmission quality for the rate adaptation. The rate adaptation includes dynamic adaptation of bandwidth and at least one other parameter. The sequence is stored as a table of vectors, each vector comprising a combination of parameters where one of parameters is bandwidth. The parameter vectors in the table are dynamically worked through in response to the channel quality estimator.
|Systems and Methods of Improved Power Amplifier Efficiency Through Adjustments in Crest Factor Reduction - Crest factor reduction algorithms described herein may be used to improve power amplifier efficiency during low signal power conditions compared to traditional static threshold techniques. Techniques described herein insure that the signal power level at the output of the crest fact reduction block is held constant relative to the input power level under all signal power level conditions. Two different solutions may be implemented together or separately to achieve the desired conditions. The first technique provides constant ratio between input power and output power. Constant ratio of peak and average output levels keeps the amount of crest factor reduction applied to the signal constant, irrespective of the signal power level. A second technique is to hold signal power level constant in respect to the amount of crest factor reduction applied.
|FREQUENCY AND TIMING OFFSET ESTIMATION ALGORITHM FOR DTV (DVB-T2) RECEIVERS - According to various embodiments, a method is disclosed that includes a method is disclosed that includes determining, by a receiver, a frequency offset in a signal comprising a set of orthogonal frequency division multiplexed (OFDM) symbols by determining a first difference in phase angles between a n
|TRANSMITTER-ONLY IC CHIP HAVING EXTERNAL LOOPBACK TEST FUNCTION AND EXTERNAL LOOPBACK TEST METHOD USING THE SAME - A transmitter-only integrated circuit (IC) chip for performing an external loopback test without an additional receive pin in a chip and an external loopback test method include drivers, mounted on the transmitter-only IC chip, for transmitting data through transmit pads that are installed in correspondence to a plurality of channels; and a loopback test circuit for receiving data as external loopback data through one of the transmit pads set as a receive pad for a test, the data being transmitted through one of the remaining transmit pads, and then comparing the received external loopback data with original transmit data.
|METHOD AND APPARATUS FOR MEASURING SIGNAL PHASE SHIFTS - A method and an apparatus for measuring a phase shift between a first and a second signal, comprising the steps of shifting the first signal in frequency by an offset frequency, superposing the frequency-shifted first signal and the second signal, determining an envelope signal of the superposed signal, and measuring a phase shift of the envelope signal at the offset frequency, or a multiple thereof, with respect to the phase of the offset frequency, wherein the phase shift is measured by determining a Fourier coefficient of the envelope signal at the offset frequency and extracting its phase. The invention further relates to an apparatus implementing the method.
|SPACE VECTOR BASED SYNCHRONOUS MODULATING METHOD AND SYSTEM - A space vector based synchronous modulating method includes sampling a frequency f of a reference voltage vector; checking a relational table of frequencies and carrier wave ratios by the frequency f so as to obtain a carrier wave ratio N; obtaining a passing angle Δθ of the reference voltage vector by Δθ=2π/N; obtaining a modulating angle θm of the reference voltage vector by θm=(Nth−1)×Δθ, in which Nth indicates which time of sampling; obtaining a modulating ratio m according to a modulating ratio-frequency curve; accounting and synthesizing an output angle of three basic voltage vectors of the reference voltage vector according to the modulating angle θm and the passing angle Δθ of the reference voltage vector and the modulating ratio m; comparing a variable quantity θf the reference voltage vector angle θ and the output angle of three basic voltage vectors, and outputting corresponding basic voltage vectors according to the comparing result; synthesizing an output voltage in accordance with the reference voltage vector by the basic voltage vectors.
|METHOD FOR TRANSMITTING DISCRETE ELECTRIC SIGNALS - The invention relates to information transmission methods, in particular to the communication interfaces of electronic devices. The inventive method makes it possible to increase the communication range and reliability by improving noise protection through the compensation of a noise signal during the transmission and reading of the signal in both wires of a communication line. The inventive method involves connecting the first pole of a voltage supply source to the first wire of a two-wire transmission line via a first resistor and connecting the second pole of said voltage supply source to the second wire of the two-wire transmission line via a second resistor. Moreover, the first and second resistors have the equal resistance values, and a receiver is connected to the two-wire transmission line between a transmitter and the voltage supply source and is provided with two current sensors. A reading signal is defined as the sum of absolute values of the measured currents.
|METHOD AND APPARATUS FOR PERFORMING LOG-LIKELIHOOD CALCULATIONS - A method and apparatus for performing calculations relating to the derivation of log-likelihood ratio (LLR) is provided. Coefficients in the use of deriving LLRs are calculated the calculation being applicable to any one of a plurality of constellation diagrams (PAM, QAM, PSK). The coefficients may be stored in a table of coefficients, the table corresponding to a particular constellation diagram and modulation scheme. A number of tables may be stored, each table corresponding to a particular modulation scheme. The coefficients are related to a symbol estimated to be closest to the received sample and the closest symbol to the estimated symbol having a complementary value for a bit for which the LLR is to be calculated. Certain coefficients or parts of coefficients may be omitted where the corresponding constellation diagram has symmetries.
|Methods, Apparatuses, System and Related Computer Program Product for Cell Type Detection - It is disclosed a method comprising including transmitting indication information indicating network cells of a first type different from network cells of a second type, the transmitting comprising including a) broadcasting control information, the indication information to be transmitted being an indication flag, b) assigning a set of synchronization information to the network cells of the first type, and broadcasting control information, the indication information to be transmitted being the synchronization information, c) reserving at least one signaling code information for the network cells of the first type, the indication information to be transmitted being the signaling code information, d) transmitting signaling information subjected to modulation by at least one predefined phase modulation or scrambling by at least one predefined scrambling sequence, the modulation or scrambling being indicative of network cells of the first and second types, and/or e) transmitting i) a PSS and a RS, ii) a SSS and a RS, or iii) a PSS and a SSS, the PSS/RS, SSS/RS or PSS/SSS having at least one predefined phase relation to each other, the at least one phase relation being indicative of the network cells of the first and second types.
|METHOD FOR DETECTING CYCLOSTATIONARY SIGNALS - A method for detecting a cyclostationary signal in a signal to be analyzed, received from a transmitter by a receiver or read from a recording medium by a reader device. According to this method, the value of a discrimination function J is estimated, expressed as a quadratic form of the cyclic correlation coefficients of the signal to be analyzed for a set (I*
|COMMUNICATION SYSTEM, COMMUNICATION METHOD FOR THE SAME AND MOBILE STATION AND BASE STATION USED FOR THE SAME - A mobile station selecting one of a plurality of bands, obtaining two restored value candidates for respective adjacent bands in higher and lower directions by increasing or decreasing a predetermined step size by using the selected value as a reference, and generating relative value information on a restored value indicating which restored value candidate increased or decreased by the step size is the restored value candidate closer to the measured value as a bitmap. The mobile station transmits the communication channel quality information of the one band and the bitmap. The mobile station measures a communication channel quality of each of the plurality of bands obtained by dividing a communication band of a downlink.
|METHOD AND APPARATUS OF DETECTING SIGNAL BASED ON MINIMUM MEAN SQUARE ERROR IN MULTIPLE INPUT MULTIPLE OUTPUT SYSTEM - A receiver in a multiple-input multiple-output (MIMO) system is provided. The receiver includes a channel estimator estimating a channel based on a receiving signal, a minimum mean square error (MMSE) based reciprocal log likelihood ratio (R-LLR) calculator connected with the channel estimator and calculating an R-LLR based on the receiving signal and the estimated channel, and a channel decoder connected with the MMSE based R-LLR calculator and decoding the channel and the receiving signal based on the calculated R-LLR, wherein the R-LLR is calculated based on the reciprocity.
|MULTI-STAGE PHASE ESTIMATION METHOD AND APPARATUS - The embodiments provide a multi-stage phase estimation method and apparatus. The apparatus i a multi-stage phase estimation configuration. Each stage of the phase estimation configuration includes metric computation modules. Each of the metric computation modules computing a distance metric and search phase angles according to an input signal and an initial search phase angle or a search phase angle of the former stage phase estimation configuration. The number of the metric computation modules is equal to that of the search phase angles of this stage. A selection module selects the search phase angle corresponding to the minimal distance metric as the phase estimation result output of this stage according to the computation results of all metric computation modules. The average time window length of the former stage phase estimation configuration is larger than that of the subsequent stage phase estimation configuration.
|COGNITIVE RADIO SPECTRUM SENSOR EMPLOYING PEAK-TO-AVERAGE RATIO AS THE SIGNAL FEATURE - A white space sensing method includes measuring a peak to average power ratio (PAPR) of a signal of a channel in a spectrum band. The method also includes determining whether a ratio of the measured PAPR to a predetermined PAPR of a modulation scheme associated with the signal meets a predetermined threshold. The method further includes indicating the channel is available for use by an unlicensed user when the ratio meets the predetermined threshold.
|METHODS OF RECEIVING MULTIPLE INPUT MULTIPLE OUTPUT SIGNALS AND RELATED COMMUNICATION DEVICES - A MIMO (Multiple-Input-Multiple-Output) receiver may receive a plurality of MIMO transport blocks transmitted from a plurality of MIMO transmission antennas over a same carrier frequency. More particularly, a MIMO signal including the plurality of MIMO transport blocks may be received through a plurality of reception antennas, and respective measures of signal quality for each of the MIMO transport blocks may be computed. A MIMO transport block may be selected from the plurality of MIMO transport blocks based on the measures of signal quality, and the selected MIMO transport block may be decoded. Responsive to failure decoding the selected MIMO transport block, processing of all MIMO transport blocks received in the MIMO signal may be terminated. Related communication devices are also discussed.
|MIRROR SIGNAL IQ-IMBALANCE CORRECTION - A system and method are provided for calibrating the IQ-imbalance in a low-IF receiver. A Test Signal can be generated in a mirror frequency and conveyed to the receiver. The power of the signal produced in the receiver from the conveyed Test Signal can be measured. In the absence of an IQ-imbalance, the Test Signal can be completely eliminated in the receiver and the corresponding measured power of the produced signal can be minimized. Accordingly, a two dimensional algorithm is described for calibrating a receiver and correcting the IQ-imbalance by adjusting the phase and gain difference between the I and Q channels in the receiver based on the measured power of the signal produced in the receiver.
|Amplitude Control In A Variable Load Environment - Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for varying symbol amplitude. In one aspect, a system includes a symbol generator that includes a waveform generator configured to output waveforms at a plurality of selectable fundamental frequencies and with a selectable duty cycle. The symbol generator can also include a bandpass filter having a pass-band that corresponds to a communications channel of a communications network. The system can also include data processing apparatus operable to interact with the symbol generator and further operable to determine that at least a threshold number of endpoints that receive symbols from the symbol generator are experiencing a same type of transmission error. In response to the determination, the data processing apparatus can cause the waveform generator to adjust at least one of the fundamental frequency or a duty cycle of the waveforms. The fundamental frequency can be adjusted to a frequency having a harmonic that is within the pass-band.
|RADIO COMMUNICATION APPARATUS AND RADIO COMMUNICATION METHOD - A radio communication apparatus and an associated method are provided. The apparatus includes a receiving unit configured to receive first data and second data, which are transmitted from a plurality of antennas for spatial-multiplexing using a plurality of blocks, into which a plurality of consecutive subcarriers in a frequency domain are divided. The apparatus further includes a calculating unit configured to calculate a first absolute CQI value per each of the blocks for the first data and a second absolute CQI value per each of the blocks for the second data, and calculate a relative value of the second absolute CQI value with respect to the first absolute CQI value, per each of the blocks. The apparatus still further includes a transmitting unit configured to transmit the first absolute CQI value and the relative value of the second absolute CQI value in the same block.
|USE OF POWERLINES FOR TRANSMISSION OF HIGH FREQUENCY SIGNALS - Communication is provided which includes receiving a transmitted radio signal at a powerline wherein the powerline functions as a receiving antenna for the wirelessly transmitted radio signal. The powerline is coupled to an input of a radio receiver using a coupler to communicate the radio signal to the radio receiver. For calibration purposes a second antenna not coupled to powerline may be used. A method for powerline communication across transformers, open circuit breakers, and other devices is also provided. In addition, a method of monitoring a device connected to a powerline is provided.
|DETECTION AND ESTIMATION OF NARROWBAND INTERFERENCE BY MATRIX MULTIPLICATION - One or more processing units are programmed to select from among M tones in a frequency domain representation of a signal, a set of tones including at least a strongest tone (relative to background noise) and a tone adjacent thereto. From among M complex numbers in the frequency domain representation of the signal, a set of complex numbers are identified and denoted as a vector Z, corresponding to the selected set of tones. Vector Z is then multiplied with each of M columns of a matrix G which is predetermined to identify a sub-resolution maxima in Z. The M products that result from the vector multiplication of Z and G are used to determine and store in memory at least one or both of: (A) a flag indicating presence or absence of narrowband interference in the signal; and (B) an estimate of a frequency of the narrowband interference.
|PEAK-TO-AVERAGE POWER REDUCTION METHOD - A method of reducing peak-to-average power in a hybrid signal is provided. The method determines peaks in power by defining a sample point by way of a digital vector and an analog vector. The digital and analog vectors are added together to generate a hybrid vector which is used to compare the sample point to the maximum desired peak threshold. An error vector is used to correct the sample point to a desired power level. Once the sample point has been corrected it can be added back to the analog signal and transmitted.
|APPLICATION-AWARE DYNAMIC BIT-LEVEL ERROR PROTECTION FOR MODULATION-BASED COMMUNICATION - In one embodiment, a device (e.g., a transmitter) determines a level of error protection of each bit position within symbols of a particular constellation map used for modulation-based communication, and also determines priority levels of application data bits to be placed into a communication frame. Application data bits may then be placed into symbols of the communication frame, where higher priority application data bits are placed into bit positions with greater or equal levels of protection than bit positions into which lower priority application data bits are placed. The communication frame may then be transmitted to one or more receivers with an indication of how to decode the placement of the application data bits within the symbols. In another embodiment, the particular constellation map may be dynamically selected from a plurality of available constellation maps, such as based on communication channel conditions and/or applications generating the data.
|HARDWARE-BASED DATA EYE TRAINING FOR HIGH SPEED LINKS - Hardware-based methods and apparatus are provided for training high speed data links used in data transfer applications. A data valid window is calibrated on one or more high speed links by determining an offset delay value for at least one datapath using a finite state machine, wherein the offset delay value is based on a maximum offset delay value and a minimum offset delay value for the at least one datapath; and delaying a read data strobe signal based upon a base delay and the offset delay value for the at least one datapath. The offset delay value can be, for example, an average of the maximum offset delay and the minimum offset delay. The received pattern can be a predefined pattern or a programmable pattern. In addition, the received pattern can cover single-bit transitions and/or multi-bit transitions.
|Method of Handling Geodesic Interpolation for MIMO Precoding and Related Communication Device - A method of reducing quantization error caused by precoding for a receiver in a wireless communication system is disclosed. The method comprising measuring channel information of a channel between the receiver and a transmitter in the wireless communication system; determining at least one precoding matrix from at least one codebook according to the channel information of the channel; determining at least one geometric coefficient according to a Geodesic interpolation algorithm and the at least one precoding matrix, for the at least one precoding matrix, respectively; and feeding back the at least one precoding matrix and the at least one geometric coefficient to the transmitter.
|Side Channel Communications - A side channel communications system disclosed herein includes a receiver device with an internal circuitry where the operational speed of the internal circuitry changes in response to an external signal. When the receiver device receives an external signal, the operational speed of the internal circuitry changes. A detector detects the change in the operational speed of the internal circuitry to generate an output value, which is decoded to determine the information communicated by the external signal. In one implementation of the side channel communications system, the external transmitter communicates the external signal in the form of a temperature signal. Alternatively, the external transmitter communicates the external signal in the form of a change in the supply voltage.
|METHOD AND APPARATUS FOR DETECTING RECEIVED SIGNAL IN WIRELESS COMMUNICATION SYSTEM - A method for detecting a received signal includes: dividing the entire band of the received signal into N frequency components where N is a natural number larger than one, and deciding a reference frequency component containing a reference frequency as a first priority sensing band among the N frequency components; deciding the sensing priorities of the other (N−1) frequency components in such a manner that the sensing priorities spread in both directions from the first priority sensing band; calculating the magnitude of each of the N frequency components in accordance with the decided sensing priorities; comparing the calculated magnitude of the frequency component with a predetermined threshold value; and when the calculated magnitude of the frequency component is larger than the threshold value, determining that the received signal exists.
|INTEGRATED TESTING CIRCUITRY FOR HIGH-FREQUENCY RECEIVER INTEGRATED CIRCUITS - An integrated circuit comprises a receiver and an oscillator circuit. The receiver has a first input port for receiving a first oscillatory input signal, a second input port for receiving a second oscillatory input signal, and an output port for delivering an oscillatory output signal which is a function of both the first input signal and the second input signal. The oscillator circuit has a first output port for delivering a first oscillatory signal, and a second output port for delivering a second oscillatory signal. The first output port of the oscillator circuit is coupled to the HF port, and the second output port of the oscillator circuit is coupled to the LO port. The integrated circuit may be designed such that the HF port may be disconnected from the first output port of the oscillator circuit without affecting the operability of the receiver. An apparatus for testing the proper functioning of an integrated circuit as described above and a method of producing a receiver are also disclosed. The method may facilitate testing a receiver die during production. In particular it may avoid the need for feeding high-frequency signals from an external apparatus to the die.
|Mechanisms for Measuring the I/Q Impairments of a Receiver - Systems and methods for measuring transmitter and/or receiver I/Q impairments are disclosed, including iterative methods for measuring transmitter I/Q impairments using shared local oscillators, iterative methods for measuring transmitter I/Q impairments using intentionally-offset local oscillators, and methods for measuring receiver I/Q impairments. Also disclosed are methods for computing I/Q impairments from a sampled complex signal, methods for computing DC properties of a signal path between the transmitter and receiver, and methods for transforming I/Q impairments through a linear system.
|Mechanism for Measuring Transmitter I/Q Impairments Using Shared Local Oscillators - Systems and methods for measuring transmitter and/or receiver I/Q impairments are disclosed, including iterative methods for measuring transmitter I/Q impairments using shared local oscillators, iterative methods for measuring transmitter I/Q impairments using intentionally-offset local oscillators, and methods for measuring receiver I/Q impairments. Also disclosed are methods for computing I/Q impairments from a sampled complex signal, methods for computing DC properties of a signal path between the transmitter and receiver, and methods for transforming I/Q impairments through a linear system.
|Mechanism for Measuring Transmitter Impairments Using Offset Local Oscillators - Systems and methods for measuring transmitter and/or receiver I/Q impairments are disclosed, including iterative methods for measuring transmitter I/Q impairments using shared local oscillators, iterative methods for measuring transmitter I/Q impairments using intentionally-offset local oscillators, and methods for measuring receiver I/Q impairments. Also disclosed are methods for computing I/Q impairments from a sampled complex signal, methods for computing DC properties of a signal path between the transmitter and receiver, and methods for transforming I/Q impairments through a linear system.
|VOLTAGE MARGIN BASED BAUD RATE TIMING RECOVERY IN A COMMUNICATION SYSTEM - Described embodiments provide a method of recovering timing data from a received signal. An analog-to-digital converter (ADC) of a receiver generates an actual ADC value for each bit sample of a received signal. Each bit sample occurs at an associated sample phase of the receiver. A margin phase detector of the receiver recovers timing information from the received signal by determining a target voltage margin value. The margin phase detector selects a window of n received bit samples, where n is a positive integer, and determines a voltage of a cursor bit of the selected window of bit samples. The margin phase detector determines, based on the target voltage margin value and the voltage of the cursor bit, whether the sample phase is correct. If the sample phase is incorrect, the margin phase detector adjusts the sample phase of the receiver by a predetermined amount.
|Method and Apparatus for Designing Modulation and Coding Set of Communication System - The present invention provides method and apparatus for designing modulation and coding set of communication System. The method for designing modulation and coding set designs a proper set of modulation and coding schemes (MCS), based on probability distribution of the quality of received signal in the communication system, so as to optimize the whole performance of the communication system. The method comprises the steps of: acquiring the probability distribution of the quality of the received signal in the communication system; performing a calculation on the target performance of the communication system based on the acquired probability distribution of the quality of the received signal and a plurality of MCSs, to design a proper set of MCSs for the communication system, so that a region where the probability of the quality of the received signal appears more frequently are provided with more levels of the MCSs.
|DEVICE AND METHOD FOR SEARCHING SELECTED FREQUENCY CHANNELS - A device and method for selecting a frequency channel of given bandwidth in a cognitive radio application is disclosed. In one aspect, the method includes evaluating, at one of a plurality of frequency bins, a function indicative of the frequency occupancy. If the evaluation result indicates free spectrum at the considered frequency bin, the previous step is repeated for a frequency bin adjacent to the considered frequency bin until the free frequency bins constitute a frequency channel of the given bandwidth. Otherwise, the method moves to select a next frequency bin to be considered. It is selected by calculating a measure of the left and right derivative of the function at the considered frequency bin, taking the measure of the left or right derivative as gradient approximation, and determining the next frequency bin by shifting the considered frequency bin over a frequency shift inversely proportional to the gradient approximation.
|Method and System for Detecting a First Symbol Sequence in a Data Signal, Method and System for Generating a Sub-Sequence of a Transmission Symbol Sequence, and Computer Program Products - A method for detecting a first symbol sequence in a data signal is described comprising receiving the data signal in which the first symbol sequence should be detected, wherein the first symbol sequence is expressable as the kronecker product of a second symbol sequence and a third symbol sequence; correlating the first symbol sequence with the third symbol sequence to generate a first correlation result; generating a second correlation result by correlating a fourth symbol sequence derived from the first correlation result with a fifth symbol sequence derived from the second symbol sequence by a transformation that maps all negative symbols of the second symbol sequence to non-negative symbols; and generating a detection result based on the second correlation result.
|METHOD AND EQUIPMENT FOR MEASUREMENTS - The invention relates to determining a quantity to be measured from a communication system, such as a transmission delay or the phase difference of clock times. Measurement messages are transmitted (
|Multiple-Input Multiple-Output System And Method - A multiple-input multiple-output (MIMO) system can transmit on multiple antennas simultaneously and receive on multiple antennas simultaneously. Unfortunately, because a legacy 802.11a/g device is not able to decode multiple data streams, such a legacy device may "stomp" on a MIMO packet by transmitting before the transmission of the MIMO packet is complete. Therefore, MIMO systems and methods are provided herein to allow legacy devices to decode the length of a MIMO packet and to restrain from transmitting during that period. These MIMO systems and methods are optimized for efficient transmission of MIMO packets.
|Systems And Methods For Digital Control Utilizing Oversampling - Methods and systems for digital control utilizing oversampling.
|QUADRATURE RECEIVER AND METHOD OF COMPENSATING FOR I/Q IMBALANCE USING A CALIBRATION SIGNAL - A quadrature demodulator receiver unit (
|TIME-DOMAIN SEARCHING IN A TEST AND MEASUREMENT INSTRUMENT - Embodiments of the invention include devices and methods for searching IQ-based time-domain traces for events, marking the events, and analyzing intervals of interest at or around the events on a display unit of a test and measurement instrument. The test and measurement instrument can include an input terminal to receive an RF signal, an ADC to digitize the RF signal, a digital downconverter to produce I (in-phase) and Q (quadrature) baseband component information from the digitized RF signal, an acquisition memory to acquire and store a record, a trace generation section to generate one or more IQ-based time-domain traces, and a search unit to scan the IQ-based time-domain traces for one or more events. The search unit can locate and mark the events for display on a display unit of the test and measurement instrument.
|Method and Apparatus for Testing Total Isotropic Sensitivity in Multi-Antenna MIMO System - The present invention discloses a method and an apparatus for testing (TIS) in a multi-antenna (MIMO) system. The apparatus includes a base station simulator, a multipath fading channel simulator and a darkroom including a measuring antenna and a device under test placed in the darkroom. During the testing, the base station simulator generates transmitting signals of multiple transmitting antennas, and the transmitting signals have characteristic of orthogonal polarization and adopt STBC or SFBC; the multipath fading channel simulator adds corresponding channel parameters and noise interference parameters to the transmitting signals, and transmits the transmitting signals which have been decayed to the measuring antenna in the darkroom to send the transmitting signals which have been decayed to the device under test; the device under test performs multi-antenna receiving on the transmitting signals, performs MRC on received signals, and acquires the (TIS) according to the received signals which have been combined.
|Doppler Frequency Estimation in Wireless Communication Systems - An apparatus and method for estimating Doppler frequency in a wireless communication network, wherein the method comprises determining a first correlation coefficient (c
|DIGITAL SUBSCRIBER LINE (DSL) NETWORK UPGRADE TOOL - A network upgrade tool creates an upgrade project designating a source digital subscriber line access multiplexer (DSLAM), a target DSLAM, and an upgrade type and determines whether the source DSLAM and target DSLAM are eligible for upgrade based on the upgrade type. At least one new digital subscriber line (DSL) path associated with the target DSLAM is identified when the source DSLAM and target DSLAM are eligible for upgrade. Pre-provisionable elements associated with the at least one new DSL path are identified and the identified pre-provisionable elements are provisioned prior to transition from at least one existing DSL path to the at least one new DSL path. A cutover selection is received that indicates that physical network changes associated with the target DSLAM have been made and non-pre-provisioned elements are provisioned following receipt of the cutover selection.
|DSL Loop Topology Recognition Based on the Insertion Loss (Hlog) Measurements - The topology of a digital subscriber line loop can play an important role in provisioning service. For example, knowledge of certain topological features in a loop can enable telecommunications companies to make better decisions about the kinds of services that can be provisioned on that loop. Additionally, knowledge of those topological features can also assist field engineers in troubleshooting problems in the field. A topology recognition engine can provide key topological features such as the loop length, presence of single and multiple bridge taps and the length of single bridge taps on a loop.
|METHOD AND APPARATUS FOR CANCELING A PEAK OF AN INPUT SIGNAL - According to certain embodiments, a method for removing a peak of an input signal includes forming a peak group including multiple peaks having an amplitude greater than a preset signal threshold value in the input signal, generating a cancellation pulse corresponding to the peak group, and generating a output signal by subtracting the cancellation pulse from the input signal.
|COMMUNICATION DEVICE - A communication device includes: a first signal generator generating an outgoing signal with a first frequency; a transmission terminal outputting the outgoing signal generated by the first signal generator; a receiving terminal receiving an incoming signal; a mixer mixing the incoming signal received by the receiving terminal with the outgoing signal generated by the first signal generator; a second signal generator generating a test signal with a second frequency different from the first frequency; and a coupling circuit coupling a line through which the test signal generated by the second signal generator is transferred with a line connecting to the receiving terminal to input the test signal into the mixer.
|Method, Apparatus and System for Returning Signal Error in Multi-Carrier Communication System - A method for returning a signal error in a multi-carrier communication system is disclosed. A specific sub-carrier interval is determined. The specific sub-carrier interval is larger than an interval between adjacent sub-carriers in the multi-carrier communication system. A signal error is returned to a central office end on a corresponding frequency in a communication frequency band of the multi-carrier communication system at the specific sub-carrier intervals.
|SYSTEM AND METHOD FOR OPTIMIZING USE OF CHANNEL STATE INFORMATION - The present invention relates to a combiner, channel identifier, OFDM receiver and method for optimizing use of channel state information of a received signal. The method comprises analyzing a received signal in a time domain and extracting from the received signal characteristics of a communication channel. The method furthermore comprises determining a dynamic indicator of channel station information accuracy based on the characteristics of the received signal. Additionally, the method comprises applying a weight to the channel state information according to the dynamic indicator.
|METHOD AND APPARATUS FOR SYNCHRONIZING HIGHLY COMPRESSED ENHANCEMENT LAYER DATA - Multimedia application data formats often use data packets and may contain packetized hierarchical layers with a base layer (BL) and one or more enhancement layers (EL). Packets that comprise variable length coded data typically provide padding bits, which can be used for adding checksum information. The checksum information refers to both, the decoded base layer and decoded enhancement layer packet data, and is used for detecting synchronization loss between the layers. Though the packets provide different individual amounts of padding bits, this variable amount of bits per packet is sufficient for adding check-sum information for synchronization related purposes. This allows e.g. out-of-sync detection even if the enhancement layer encoding provides no overhead information for synchronization, in particular no packet headers and no packet synchronization words.
|ARITHMETIC CIRCUIT, SIGNAL SELECTION METHOD, AND COMPUTER PROGRAM - An arithmetic circuit includes: a detection unit that detects a code error for plural signals respectively modulated by different modulation methods and encoded by a predetermined encoding method; a measurement unit that measures a number of times of signal variations at a predetermined frequency or less generated in the plural signals in a period from detection of the code error in the detection unit to first detection of predetermined data contained in the plural signals with respect to each of the plural signals; and a selection unit that selects one signal from the plural signals based on a measurement result of the measurement unit.
|AMPLITUDE PROBABILITY DISTRIBUTION MEASUREMENT APPARATUS - There is disclosed a general-purpose APD measurement apparatus capable of changing a measurement condition, such as the number of channels or a resolution bandwidth (RBW) in compliance with a standard for the subject of measurement, measuring various subjects of measurement, and correcting measurement equipment, thereby enabling a higher accuracy of measurement. The resolution bandwidth (RBW) or the number of channels when measurement is performed can be flexibly changed by controlling the cycle of a clock signal whose data are sampled by A/D conversion means
|SYSTEM AND METHOD TO CALIBRATE THE FREQUENCY RESPONSE OF AN ELECTRONIC FILTER - A system and method provide for calibrating the frequency response of an electronic filter. The system and method include a radio transmitter with both in-phase and quadrature baseband paths. Each baseband path includes a numerically controlled oscillator ("NCO"), a digital signal path, a digital-to-analog converter ("DAC"), and an analog filter. A low frequency tone is applied from the NCO from one of the baseband path, while a high frequency tone is applied from the NCO in the other baseband path. An analog peak detector at output determines which analog filter has the largest amplitude at the output. The peak detector offset between the two analog filters is offset by stimulating the in-phase and quadrature baseband paths with the respective NCOs to find an amplitude difference between the output signals from the NCOs that makes the output of the analog filters the same. Calibration is then performed on the corner frequency and filter peaking through respective stimulation of the in-phase and quadrature baseband paths. The system and method is advantageous as it allows for very accurate calibration of both the filter corner frequency and peaking during a standard transmission operating mode with little additional hardware required.
|USING EQUALIZATION COEFFICIENTS OF END DEVICES IN A CABLE TELEVISION NETWORK TO DETERMINE AND DIAGNOSE IMPAIRMENTS IN UPSTREAM CHANNELS - A system estimates impairment contributions for upstream communications in a cable television system. The system receives equalization coefficients used by end devices in the cable television system. The equalization coefficients are used by equalizers to mitigate distortion in upstream channels for the end devices. The system analyzes the coefficients based on impairment thresholds to determine whether impairment problems exist and to identify the types of impairment problems that exist.
|Dynamic Allocation of Transceivers and Frequency Channels in MIMO Systems - A communication system is provided that switches the communication of multi-antenna transmitter and receiver terminals between MIMO and frequency-bundle modes. In MIMO mode all transmitter and receiver antennas operate in the same frequency channel while in frequency-bundle mode each pair of one transmitter antenna and one receiver antenna is tuned to a different frequency channel. The communication system includes one or more control modules that collect, analyze, and apply configurations to the terminals and switch the operation of one or more transmit/receive terminal pairs between the MIMO and frequency-bundle modes based on the collected information and metrics. The monitored information and metrics include the availability of idle frequency channels in the available frequency band, propagation channel conditions, peak throughput demand by different users, power consumption budget and battery lives of different terminals, distance between transmitter and receiver antennas in each communicating transmitter/receiver pair, and overall traffic demand by terminals.
|Integrated Circuit Including Pulse Control Logic Having Shared Gating Control - An integrated circuit with a pulse clock unit having shared gating control includes one or more logic blocks, each including a clock distribution network configured to distribute a clock signal. The integrated circuit also includes a clock unit coupled to the one or more logic blocks and configured to generate a pulse clock signal formed using a chain of inverting logic gates. The clock unit may be further configured to provide the pulse clock signal to the clock distribution network. The clock unit may also include an enable input that is coupled to one input of one of the inverting logic gates. In addition, the clock unit may be configured to selectively enable and disable the pulse clock signal in response to an enable signal on the enable input.
|Method to Detect Data Transmitted by Multiple Antennas - The present invention relates to a system and a multistage signal detection method to jointly detect the data symbols transmitted from multiple transmit antennas in a communication terminal and received using multiple receive antennas in another communication terminal.
|CLOSED LOOP POWER NORMALIZED TIMING RECOVERY FOR 8 VSB MODULATED SIGNALS - A timing recovery loop includes a sampler, a narrow band filter, an RMS normalizer, a timing error detector, and a sample controller. The sampler samples a received signal. The narrow band filter filters the sampled received signal so as to pass an upper band edge of the received signal and not a lower band edge of the received signal. The RMS normalizer sets an average power level of an output of the filter to a substantially constant value. The timing error detector detects a timing error with respect to an output of the RMS normalizer. The sample controller controls the sampler in response to the detected timing error.
|BACKOFF ADAPTATION FOR DIGITAL COMMUNICATION SYSTEMS WITH CHANNEL QUALITY INFORMATION - System and method for backoff correction of channel quality information (CQI). A correction factor is calculated based on a goodness measure such as packet error rate (PER). The selection of modulation and coding scheme (MCS) is made considering the channel quality information (CQI) adjusted by the correction factor. A meaningful goodness measure can be imposed if the goodness measure is very low. A different correction factor can be calculated for different confidence levels, MCSs and transmission modes.
|System and Method for Adapting Codebooks - A system and method for adapting codebooks are provided. A method for communications device operations includes receiving a pilot signal, computing a channel estimate for a channel between a controller and a communications device, the computing being based on the pilot signal, adapting a codebook based on the channel estimate and positions of codewords in the codebook, computing a representation of the channel using the adapted codebook, transmitting the representation of the channel as feedback information, and receiving a transmission beamformed based on the feedback information.
|POWER BACK-OFF MODE AND CIRCUIT FOR 100BASET - Generally, 100BaseT allows for the establishment of links on cables (such as Category 5 or CATS cables) up to 120 m or more in length. In a given industrial Ethernet system, many of the cables deployed will be less than 120 m in length, and, in fact, many of the cables are much shorter than 120 m. Yet, the transmission amplitude output from each unit is generally the same, regardless of cable length. Here, Power Back Off (PBO) circuitry is provided in a unit that operates in a PBO mode to passively estimate a cable length and adjust its corresponding transmission amplitudes to generally match the estimated cable length so as to reduce power consumption.
|Power Allocation in a Wireless System with Base Stations Having Antenna Arrays - Provided is a method and apparatus for allocating transmit power in a wireless network. The method includes determining powers at which a base station transmits downlink signals to each active user equipment associated with the base station such that each of the downlink signals is associated with a different active user and the base station is permitted to transmit downlink signals with different powers to the associated active user equipments. The method further includes transmitting the associated downlink signals, by the base station, to the active user equipments at the determined powers.
|OFDM Speed Estimation - Techniques are provided for deriving speed estimates by performing a convolution of the output of the Fast Fourier Transform (FFT) stage from different time windows in an orthogonal frequency-division multiplexing (OFDM) modulation scheme. Such techniques enable speed estimation to be performed in the frequency domain, requiring little or no modification to existing OFDM systems.
|SIGNAL PROCESSING APPARATUS AND METHOD - A signal processing apparatus includes a number P of adaptive equalization filters, P being 2 or more, configured to execute a first computing process for equalization on respective input signals, and to issue output signals; a number N of error calculation circuits, N being not more than P, configured to determine, per adaptive equalization filter, a second computing process to calculate an error in order to reduce a difference between a value of the output signal obtained with the first computing process and a predetermined objective value of the output signal; and an update circuit configured to determine a third computing process based on the second computing process determined per adaptive equalization filter by the error calculation circuit, and to update a computing process, which is executed in the adaptive equalization filter, to the third computing process.
|MULTI-DOMAIN TEST AND MEASUREMENT INSTRUMENT - A test and measurement instrument including a time domain channel configured to process a first input signal for analysis in a time domain; a frequency domain channel configured to process a second input signal for analysis in a frequency domain; and an acquisition system coupled to the time domain channel and the frequency domain channel. The acquisition system is configured to acquire data from the time domain channel and the frequency domain channel. Time domain and frequency domain data can be time aligned.
|SELECTIVE JOINT DEMODULATION - Systems, methods and apparatuses for jointly demodulating data signals are disclosed. In accordance with the method, pilot signals are received from a base station and are processed. In addition, from a set of expected co-scheduled data streams, a subset of the co-scheduled data streams that are actually transmitted by the base station are determined based on the pilot signals. Further, a group of the transmitted co-scheduled data streams are selected from the determined subset. The data signals are received and jointly demodulated by employing the selected group of co-scheduled data streams and by suppressing non-selected data streams from the determined subset.
|CALIBRATION METHOD PERFORMING SPECTRUM ANALYSIS UPON TEST SIGNAL AND ASSOCIATED APPARATUS FOR COMMUNICATION SYSTEM - A calibration method for calibrating a communication system includes: generating a test signal at a transmitter; configuring at least one calibration coefficient at the transmitter; configuring at least one calibration coefficient at the receiver; transmitting the test signal to a receiver via the calibration coefficient; performing a spectrum analysis upon the test signal received by the receiver to generate a spectrum analysis result; and adjusting the calibration coefficient according to the spectrum analysis result to calibrate the transmitter. In addition, a calibration method is also provided for calibrating a receiver of a communication system, and related calibration apparatuses are further provided.
|CHANNEL ESTIMATION TECHNIQUE FOR MULTI-CARRIER SYSTEM - The present invention relates to a channel estimation technique for multi-carrier system which uses pilot signal to first obtain pilot subcarrier channel responses, then estimate the mean delay and the root-mean-square delay spread of the channel, and then uses interpolation to obtain the channel responses of arbitrary subcarriers. The present invention is able to perform channel estimation and to accurately estimate various channel delay parameters (such as the initial delay, the mean delay, and the root-mean-square delay spread) with very low quantity of pilot signal and with low computational complexity. In addition, the present invention has broad applicability, as it does not require the channel power-delay profile to be of certain specific types and it can operate in systems where pilot subcarriers have an irregular configuration.
|MULTIPLE INPUT MULTIPLE OUTPUT COMMUNICATION SYSTEM AND COMMUNICATION METHOD OF ADAPTABLY TRANSFORMING CODEBOOK - A multiple input multiple output (MIMO) communication system including a base station and at least one terminal may adaptively transform a codebook. The terminal may calculate one or more correlation matrices based on one or more subchannel matrices included in a channel matrix. The terminal may feed back information for the base station to reconstruct the one or more correlation matrices. The terminal may transform a codebook stored in the memory of the terminal, based on the one or more correlation matrices. The base station may verify the one or more correlation matrices using the information for the base station to reconstruct the one or more correlation matrices. The base station may transform a codebook stored in the memory of the base station such that the transformed base station codebook is the same as the transformed terminal codebook.
|Method For Analyzing Random Telegraph Signal And Threshold Level Determination Method Therefor - A method for analyzing a random telegraph signal according to the present invention includes the steps of: performing band-pass filter processing with respect to signal data; subsequently calculating a histogram; subsequently performing threshold determination processing; further performing, based on a result of the threshold determination, binarization processing with respect to the filtered signal data; and further obtaining, based on a result of the binarization, coefficients τ.
|METHOD FOR TESTING A RADIO FREQUENCY (RF) RECEIVER AND RELATED METHODS - A method for testing a radio frequency (RF) receiver may include measuring a plurality of bit error levels for the RF receiver at a given RF frequency. The method may further include applying a Huber function to the measured plurality of bit error levels to generate a bit error ratio (BER) estimate for the RF receiver. The method would also include using the BER estimate to generate a sensitivity for the RE receiver.
|APPARATUS FOR DECOUPLING A RADIO-FREQUENCY SIGNAL TRANSMITTED ON A DATA TRANSMISSION LINE - An apparatus for decoupling a radio-frequency signal transmitted on a data transmission line having a first line element and a second line element, or for decoupling interference voltages includes: a tapping module, connected to the first and second line elements at a first tapping location of the data transmission line, for decoupling the radio-frequency signal or interference voltages; a current probe module, coupled to the first line element at a second tapping location of the data transmission line; and an output capable of being matched to different input impedances of a device connected to the output.
|METHOD FOR DECODING A COMPOSITE RADIO SIGNAL AND CORRESPONDING RECEIVER - The present invention relates to a method for decoding a composite radio signal at a receiver in an OFDM based radio communication system, said composite radio signal being a superposition of at least two signals sent by at least one transmitter, each signal having signal properties, in particular modulation scheme, coding scheme, said at least two signals being transmitted using the same radio resource on a set of frequency subchannels of said OFDM system.
|DEVICE, CHANNEL QUALITY ESTIMATION METHOD, AND TRANSMISSION METHOD - A mobile device includes a first receiving unit that receives a dedicated pilot signal included in a dedicated pilot signal part of a data unit that is transmitted from a base station to the self-device, an second receiving unit that receives a signal included in a dedicated pilot signal part of a data unit that is transmitted from the base station to the other device other than the self-device, a CQI generating unit that estimates a channel quality indicator that indicates a reception environment when the self-device receives data on the basis of the dedicated pilot signal received by the first receiving unit and the signal received by the second receiving unit, and a radio unit that transmits the channel quality indicator estimated by the CQI generating unit to the base station. Therefore, the present invention can contribute to the assignment optimization of a radio resource of the base station.
|Interpolating GRAKE with Two Step Delay Hypothesis Testing - The present invention provides a method and apparatus for adapting a current path delay estimate for path delay tracking. The method comprises selecting an operating mode, determining a set of hypothesized path delays based on said operating mode, computing a metric for each hypothesized path delay, and adapting a current path delay estimate based on the computed metrics for the hypothesized path delays.
|OPERATING ENVIRONMENT ANALYSIS TECHNIQUES FOR WIRELESS COMMUNICATION SYSTEMS - Methods and systems of analyzing an operating environment of wireless communication equipment in a wireless communication system are provided. A stimulus in the operating environment at a location of the wireless communication equipment is sensed and linearly expanded in Slepian sequences using a multitaper spectral estimation procedure. A singular value decomposition is performed on the linearly expanded stimulus, and a singular value of the linearly expanded stimulus provides an estimate of interference at the location of the wireless communication equipment.
|Architecture to Remove a Bimodal Dynamic DC Offset in Direct Conversion Receiver - Apparatus for controlling the generation of a DC signal at the output of a mixer, so that the DC signal is predictable, enabling a static offset compensation voltage to offset the DC signal. The apparatus comprises a mixer configured to receive a first and a second input signal, the mixer being such as to generate a first DC signal at the output of the mixer when the first and second input signal have the same frequency and a first relative phase, a phase detector for determining the relative phase of the first and second signals, and a phase modifier configured to modify the phase of the second signal relative to the first signal in dependence on the determination of the relative phase between the first and second signals such that the resulting DC signal at the output of the mixer is the first DC signal.
|METHOD, DEVICE AND COMPUTER READABLE MEDIUM FOR DETERMINING WHETHER TRANSMISSION SIGNALS ARE PRESENT IN RECEIVED SIGNALS - A method is provided for determining whether transmission signals are present in received signals, the method comprising: receiving a first signal via a first radio resource; receiving a second signal via a second radio resource; determining whether a first transmission signal is present in the received first signal based on the received second signal; and determining whether a second transmission signal is present in the received second signal based on the received first signal.
|RECEIVING DEVICE AND RADIO QUALITY CALCULATION METHOD - A reception device calculates a radio quality in a downlink by using a plurality of pilot symbols transmitted from a base station. The reception device includes a correlation calculation unit and a radio quality calculation unit. The correlation calculation unit calculates a correlation value between a first pilot symbol and a second pilot symbol on a time axis or a correlation value there between on a frequency axis. If the correlation value obtained by the correlation calculation unit exceeds a predetermined threshold value, the radio quality calculation unit calculates a radio quality in the downlink by using a reception quality of the first pilot symbol and a reception quality of the second pilot symbol.
|METHOD AND SYSTEM FOR IMPULSIVE NOISE CLASSIFICATION AND MITIGATION - A system for classifying impulsive noise on a communications signal comprises an impulse signal generator, an integrator, a first comparator, and an impulse peak detector. The impulse signal generator receives a communications signal that includes impulsive noise and is configured to provide an impulse signal that includes just the impulsive noise. The integrator receives the impulse signal and integrates the impulse signal to determine the power of the impulse signal. The first comparator receives the impulse signal and is configured to compare the impulse signal to a first reference signal and indicate the time during which the value of the impulse signal is greater than the value of the first reference signal. The impulse peak detector receives the impulse signal and is configured to process the impulse signal, compare the processed signal to a second reference signal, and detect the peak value of the impulse signal.
|Method and a System for Estimating a Symbol Time Error in a Broadband Transmission System - The invention relates to a method and a system for estimating a symbol time error in a broadband transmission system, comprising: determination a time error signal of an output-signal of a discrete Fourier-transformation block (
|Apparatus and Method for Monitoring Data Transmitter - For monitoring a data transmitter such as a streaming server, which supplies transmitted data in response to a request of a receiver, an examiner examines a data traffic at the input of a receiver or at the output of the receiver, the examiner being configured to ascertain whether the data traffic falls below a minimum threshold. If the minimum threshold is fallen below, a connection activator initiates a new connection between the receiver and the data transmitter. This serves to enable consistent data-transmitter monitoring, even for non-reliable point-to-point connections via the internet.
|ELECTRICAL PULSE DATA TRANSMISSION USING A LOOK-UP TABLE - Input data is encoded using a look-up table and then transmitted over a conductive transmission medium as a series of electrical pulses. The look-up table includes data elements. The length of each pulse is calibrated to correspond to one of the data elements in the look-up table. Upon receipt at another end of the transmission medium, the data is decoded using a look-up table. This decoding includes measuring the length of each received pulse to match the measured length to a corresponding one of the data elements in the look-up table.
|System forTransmission of Signals in a Domestic Environment - The present invention relates to a wireless transmission system for signals intended more specifically for a domestic environment. It includes a central terminal comprising at least m transmission channels and n directive transmission antennas intended to transmit first signals at least one client terminal having at least one reception channel connected to a reception antenna in order to receive the first signals said central terminal and said client terminal communicating in a transmission channel having a predetermined frequency band, and an estimation device able to generate an item of information representative of the reception quality of first signals in at least one point of a predetermined geographic zone associated with the client terminal and a return channel in order to transmit said at least one item of information to the control means of the central terminal.
|Modulation Evaluation System - A modulation evaluation system associated with frequency modulations periods of a phase-locked loop is described. The system includes a first accumulator for accumulating clock edges a window of the frequency modulation periods; a second accumulator coupled to the first accumulator and operative for accumulating clock edges during whole periods of the frequency modulation periods; a dynamic enable control coupled to a first input associated with the first accumulator and a second input associated with the second accumulator, wherein the dynamic enable control selectively transmits a first enable signal that controls when the first accumulator accumulates clock edges and a second enable signal controls when the second accumulator accumulates clock edges, and accumulating clock edges enable modulation evaluation during production.
|Power-Indexed Look-Up Table Design of Digital Pre-Distortion for Power Amplifiers with Dynamic Nonlinearities - This invention is a method of power amplifier digital pre-distortion which measures a current power level of the power amplifier, stores in a look up table entries consisting of a power level and a corresponding set of digital pre-distortion coefficients, selects a set of digital pre-distortion coefficients corresponding to the measured power level. If the measured current power level is near a power level index, the digital pre-distortion coefficients correspond to the power level index. If the measured current power level is greater than the maximum power level entry, the digital pre-distortion coefficients is of the maximum power level entry. If the measured current power level is less than the minimum power level entry, the digital pre-distortion is of the minimum power level entry. If the measured current power level is not near a power level index, the digital pre-distortion coefficients are an interpolation.
|SERIAL BIT STREAM REGULAR EXPRESSION ENGINE - A test and measurement instrument including a user interface; and a controller is described. The controller is configured to receive a serial bit stream; apply a regular expression to the serial bit stream; and present acquired data, or other data, through the user interface in response to the application of the regular expression to the serial bit stream.
|System Optimization Using Soft Receiver Masking Technique - Communication system optimization using a soft receiver masking technique is disclosed. For example, a method for testing a communication device comprises obtaining a software representation of a receiver portion of a given communication device. A data signal received from a transmitter through a given link channel is then processed, wherein the processing step is performed using the software representation of the receiver portion of the communication device. An output signal is caused to be generated by the software representation of the receiver portion. An eye mask test is then applied to the output signal. Based on a result of the eye mask test, one or more parameters of the transmitter may be adjusted.
|System and Method for Non-Uniform Bit Allocation in the Quantization of Channel State Vectors - A system and method for non-uniform bit allocation in the quantization of channel state vectors is provided. A method for communications node operation includes receiving a bit-allocation profile for use in quantizing channel state information, measuring a communications channel between the communications node and a controller, generating channel state information based on the measurement, computing a bit representation of the channel state information, transmitting the bit representation to the controller, and receiving a transmission from the controller. The computing makes use of quasi-tail-biting trellis decoding, and the computing is based on the bit-allocation policy. The transmission makes use of the channel state information transmitted by the communications node.
|Automated Line Test Action and Monitoring System - A method includes identifying, at a computing system executing a line test engine, a line to be tested by comparing a test entry of a test configuration database to a first database. The first database includes line data descriptive of multiple lines of a network. The method includes determining, at the computing system, a test to be performed on the line based on the test entry and sending a message from the computing system to a line test controller. The message indicates the line and the test to be performed on the line. The line test controller causes a test device to perform the test on the line. The method includes receiving a result message from the line test controller, wherein the result message indicates a result of the test.
|WIRELESS COMMUNICATION DEVICE AND WIRELESS COMMUNICATION SYSTEM - The present invention provides a wireless communication device and a wireless communication system which can improve the error detection accuracy with the sound quality maintained to some extent even if the communication environment is deteriorated. A cordless phone establishes a digital link on a wireless channel between a master device and a slave device, compresses a sound signal in an ADPCM scheme, and carries the sound signal in a sound packet to perform communication. In a master device side, a PCM signal is converted into ADPCM data by an ADPCM encoding unit. Next, the least significant bit of n-bits is set according to the number of "1" of the n-bits of the ADPCM data by a transmission conversion table. In a slave device side, it is determined whether an error has occurred according to the number of "1" of the n-bit data in received data. If the error exists, the n-bit sound data is converted into mute data through a reception conversion table. The sound data converted through the reception conversion table is converted into a PCM signal from an ADPCM format by an ADPCM decoding unit.
|Method and Arrangement for Measuring Delay of a Signal Between Two Stations of the Arrangement - A method and an arrangement for determining the delay of a signal between a first station and a second station of the arrangement, with the aim of determining the spatial distance between the stations. A first series of first signal pulses is generated in the first station at a first pulse repetition rate f
|Method and System for the Serial Transmission of Data - There is provided a system for the bidirectional synchronous transmission of data between a device (
|GEOMETRIC DETECTOR FOR COMMUNICATING THROUGH CONSTANT MODULUS (CM) INTERFERERS - A desired signal modulated with N symbols is detected in the presence of a constant modulus (CM) interferer that produces M symbols. Observation samples corresponding to the desired signal and the interferer are obtained from a signal recovery stage. N observation constellations are defined, each having M constellation points corresponding to the symbols produced by the interferer, and the points form a circular perimeter of the constellation with a radius corresponding to the strength of the interferer. The perimeter of each constellation is centered on one of N defined symbol points representing the different possible symbols of the desired signal. Distances between the observation samples and the circular perimeter of each observation constellation are determined. For each observation sample, the symbol point on which the constellation perimeter closest to the sample is centered, is selected as a symbol of the desired signal.
|Technique for Controlling a Gain of a Receiver - A technique for controlling a gain of a receiver is provided. A method implementation of this technique comprises the steps of receiving at least one signal, initially controlling the gain of the receiver based on a correlation value of a first part of the received signal having a substantially constant signal strength, determining at least one timing-related parameter of the received signal based on the at least first part, identifying based on the at least one timing-related parameter at least a second part of the received signal having a substantially constant signal strength and further controlling the gain of the receiver based on a measured signal strength of the identified second part.
|SYSTEM AND METHOD FOR TESTING RADIO FREQUENCY WIRELESS SIGNAL TRANSCEIVERS USING WIRELESS TEST SIGNALS - A method of facilitating wireless testing of multiple radio frequency (RF) signal transceiver devices under test (DUTs). Using multiple antennas within a shielded enclosure containing the DUTs, multiple wireless RF test signals radiated to the DUTs can have their respective signal phases controlled to maximize the direct-coupled signals to their respective intended DUTs while minimizing the cross-coupled signals. Additionally, the wireless RF test signals radiated to the DUTs can have their respective signal magnitudes controlled to normalize the direct-coupled signals to their respective intended DUTs while still sufficiently reducing the cross-coupled signals. As a result, compensation is provided for the multipath signal environment within the shielded enclosure, thereby simulating wired test signal paths during wireless testing of the DUTs.
|TEST SIGNAL GENERATION AND APPLICATION IN RECEIVERS - One embodiment of the present invention relates to a test signal generator configured to generate a single sideband (SSB) test signal that is used for testing components of one or more receiver chains to identify errors in the receiver chains. In one embodiment, the circuit comprises a SSB signal generator configured to generate an IQ baseband signal comprising a sequence of constellation points corresponding to the SSB test signal. The constellation points are modulated onto a high frequency local oscillator signal to generate the SSB test signal, which is inserted into a reception path of a receiver at a test signal injection point. The reception path comprises a mixer configured to mix the SSB test signal with the local oscillator signal to generate a down-converted, intermediate frequency output signal. The output signal may be analyzed to determine errors in the reception path.
|Wireless Communication System Mapping Data Bits to Symbol Bit Positions According to Error Rates of Those Bit Positions and Data Content - A transmitter-receiver pair encode data as transmitted symbols according to knowledge about variations in noise immunity between different bit positions of the symbols as a decoded. High usefulness data may be preferentially encoded at those bit positions having greatest noise immunity to improve transmission effectiveness.
|METHODS AND SYSTEMS FOR MEASURING DATA PULSES - Some embodiments disclosed herein relate to a method. In the method, a duration of a first synchronization pulse is measured. A fixed, predetermined number of ticks are equally spaced at a first time interval over the first sync pulse, regardless of the duration of the first synchronization pulse. A duration of a first data pulse is then measured by periodically incrementing a tick count value at the first time interval during the entire duration of the first data pulse. The tick count value at an end of the first data pulse is then correlated to a first digital value encoded on the first data pulse.
|CHANNEL ESTIMATION METHOD AND APPARATUS FOR WIRELESS COMMUNICATION SYSTEM - A channel estimation method and apparatus using a self-tracking algorithm is provided for improving channel estimation accuracy. The channel estimation apparatus of a mobile terminal includes a receiver for converting a received radio signal into a baseband signal, a match filter for converting the baseband signal into a digital signal including at least two samples, a channel estimator for buffering the samples, for analyzing multipath signals to predict a maximum power position and multipath energy, and for estimating a channel by selecting a multi-tap at the maximum power position through a slew control, an equalization controller for calculating an equalization tap gain using the multi-tap selected by the channel estimator, and an equalizer for compensating for distortion in the samples output by the channel estimator using the equalization tap gain calculated by the equalization controller.
|WIRELESS REMOTE SENSING SYSTEM USING SURFACE ACOUSTIC WAVE SENSOR - In an ON state, a first switch generates a transmission signal by pulse modulating a carrier. A SAW sensor outputs a reception signal after a delay from receipt of the transmission signal. In an input state, a second switch receives and transmits the transmission signal to the SAW sensor. In an output state, the second switch receives and outputs the reception signal. A SAW delay element outputs a local signal after the delay from receipt of the transmission signal. A mixer generates a synchronous detection signal by mixing the reception and local signals. During the input state of the second switch, the first switch switches from the OFF state, to the ON state, and back to the OFF state. The second switch switches from the input state to the output state before the delay after the first switch switches back to the OFF state.
|BURST TRIGGERED SIGNAL ANALYSIS - An apparatus can include a detector configured to detect a burst event for a selected frequency of a digital input signal having a predetermined bandwidth. The detector can provide a burst trigger, in response to detecting the burst event relative to a threshold, and provide other burst data for the detected burst event. A signal analyzer can be configured to measure signal information for another selected frequency of the digital input signal in response to the burst trigger. The signal analyzer can provide corresponding analysis data based on the measured signal information, the burst trigger, the other burst data, and the corresponding analysis data can be stored in memory.
|RADIO COMMUNICATION DEVICE AND METHOD - A radio communication device includes a first filter configured to receive a first transmission signal, a second filter configured to receive a second transmission signal orthogonal to the first transmission signal, a radio unit configured to perform quadrature modulation on signals output from the first filter and the second filter, and produce a radio signal, a switch configured to provide, when a first test signal and a second test signal are present, the radio signal to a reception unit as a corresponding test radio signal, and a baseband signal processing unit configured to compensate for in-phase/quadrature imbalance by outputting the first test signal to the first filter, output the second test signal to the second filter, and calculate, on a basis of the test radio signal received via the reception unit, a correction factor to be applied to the first transmission signal and the second transmission signal.
|COMMUNICATION ANALYSIS APPARATUS AND COMMUNICATION ANALYSIS METHOD - To obtain a communication analysis apparatus and a communication analysis method that are allowed to analyze a communication message and a waveform signal in such a manner that the communication message and waveform signal are associated with each other.
|PHOTONIC CELL CONTROL DEVICE AND METHOD FOR ULTRA-WIDEBAND (UWB) TRANSMITTERS/RECEIVERS - The present disclosure relates to a cell organisation and method for controlling ultra-wideband (UWB) transmitting/receiving devices, the aim of which is to improve spatial occupancy (number of transmitters/receivers operating per unit area) and spectral efficiency (number of transmitters/receivers operating in a certain frequency range) in a predetermined area. The control method is based on configuring the optimum parameters—transmission power, bandwidth among others—for each UWB transmitter/receiver present in each cell. Said configuration is calculated by monitoring the spectral parameters of the UWB transmitters/receivers operating in the area under control using a series of UWB sensors. In a preferred embodiment of the disclosure the sensors can be interconnected using photonic technology.
|ELECTRONIC DEVICE INSTRUCTIONS PROVIDED USING RADIO SIGNALS - Systems, methods, and machine-readable media are disclosed for controlling an electronic device using data transmitted over radio signals. In some embodiments, a radio source may embed instructions to control an electronic device into a radio signal. For example, the radio source may use the RDS communications protocol to transmit the instructions in an FM radio signal. The electronic device may receive the radio signal and may perform the instructions included in the radio signal. For example, in a testing environment, the instructions can include commands to test the electronic device's radio using test parameters specified in the instructions. Responsive to receiving the test parameters, the electronic device may configure itself (e.g., turn on or off certain components) and record audio from a specified radio station.
|Radio Frequency Integrated Circuit with On-Chip Noise Source for Self-Test - Radio frequency integrated circuits with on-chip noise source for use in the performance of tests and/or calibrations. For example, a radio frequency integrated circuit comprises at least one noise source residing on the radio frequency integrated circuit, the noise source being controllable by a digital input, and a radio frequency circuit residing on the radio frequency integrated circuit and being coupled to the noise source, wherein at least one attribute of the radio frequency circuit is determinable by controlling the noise source via the digital input.
|METHOD USING EQUALIZATION DATA TO DETERMINE DEFECTS IN A CABLE PLANT - A method of estimating a defect location within a network is provided. Information of pre-equalization coefficients of an adaptive pre-equalizer of a terminal network element on the network is received. A total amount of equalization applied by a negative delay portion of the adaptive pre-equalizer relative to a main tap level and a total amount of equalization applied by a positive delay portion of the adaptive pre-equalizer relative to the main tap level is determined. The terminal network element is determined as being affected by a defect if at least one of the total amount of equalization applied by the negative or positive delay portions relative to the main tap level is at an unacceptable level. If a defect is identified, a location of the defect is estimated differently depending upon whether the negative or positive delay portion of the adaptive pre-equalizer applies the greatest amount of equalization.
|APPARATUS AND METHODS FOR LOSS OF SIGNAL DETECTION - Apparatus and methods for loss of signal detection are provided. In one embodiment, a detection circuit for monitoring an input includes a small signal boost circuit, a rectifier circuit, a low-pass filter, and one or more comparators. The small signal boost circuit can generate an amplified signal by providing a first amount of gain to an input signal when the input signal is relatively small, but can saturate and provide reduced gain without external gain control adjustment when the input signal does not have a relatively small magnitude. The rectifier circuit can rectify the boosted signal to generate a rectified signal, and the low-pass filter can filter the rectified signal to generate a filtered signal. The one or more comparators can compare the filtered signal to one or more decision threshold voltages to determine the presence or absence of the input signal on the input.
|ADAPTIVE FILTER BANK FOR DYNAMIC NOTCHING IN POWERLINE COMMUNICATION - An adaptive filter bank can be implemented on a PLC device to dynamically adapt to variations in notching requirements and the performance of the PLC medium. The PLC device can apply filter coefficients to one or more filter elements of the adaptive filter bank to generate one or more notched subcarriers in the PLC band. A performance measurement of one or more subcarriers in the PLC band can be determined and evaluated against corresponding performance measurement thresholds. For a given notched subcarrier, if the performance measurement of the corresponding subcarriers is not in accordance with the performance measurement threshold, updated filter coefficients for the filter element configured to generate the notched subcarrier can be determined based, at least in part, on the performance measurement of the one or more subcarriers. The filter coefficients of the filter element can then be updated using the updated filter coefficients.
|DIGITAL COMMUNICATIONS TEST SYSTEM FOR MULTIPLE INPUT, MULTIPLE OUTPUT (MIMO) SYSTEMS - A digital communications test system and method for testing a plurality of devices under test (DUTs) in which multiple sets of a single vector signal analyzer (VSA) and single vector signal generator (VSG) can be used together to perform error vector magnitude (EVM) measurements for one or more DUTs in parallel, including one or more of composite, switched and multiple input multiple output (MIMO) EVM measurements. This allows N pairs of a VSA and VSG to test N DUTs with NxN MIMO in substantially the sane time as a single VSA and VSG pair can test a single DUT, thereby allowing a substantial increase in testing throughput as compared to that possible with only a single VSA and VSG set.
|ESTIMATING SYSTEM AND TRAFFIC DATA IN A DOCSIS SYSTEM - Methods for computing system data (e.g., the number of CMs per DS-SG or US-SG) and traffic data (e.g., the number of online CMs, the number of active CMs, the percentage of time a CM is online, the percentage of time a CM is active, and the concurrency of CMs) in a DOCSIS system are disclosed.
|Diversity With a Coded Signal - A communications device configured to generate a first diversity signal comprising: a first single coded signal spanning a first frequency sub-band, and a second single coded signal contemporaneous with the first single coded signal spanning a second frequency sub-band offset from the first frequency sub-band such that the total bandwidth of the first diversity signal is greater than the bandwidths of either of the first and second frequency sub-bands alone; and a signal transmitter configured to transmit the first diversity signal to a first counterpart communications device; said first and second single coded signals each being such that, after undergoing a procedure comprising being: transmitted, received, shifted into a receiver frequency sub-band spanning a narrower bandwidth than the total bandwidth of the first diversity signal, and cross-correlated with a replica signal based on the transmitted signal, a single significant peak corresponding to the most direct transmission path is produced.
|Systems and Methods for Probing Wired Communication - Various systems and methods for probing a communication channel. These systems and methods transmit an error vector probe packet from a first transmitter while a second transmitter is active and transmitting. A network device may receive the error vector probe packet and measure an error vector magnitude based on the received error vector probe packet. Using the error vector magnitude, the network device estimates channel characteristics such as signal-to-noise ratio, data capacity, etc. The transmission can occur when more than one transmitter is active and transmitting. At least some of the other transmitters are active and transmit an analog zero signal, e.g., all digital zeros on the input to the digital-to-analog converter of a network device when an error vector probe packet is transmitted.
|COMMUNICATION SYSTEM AND METHOD FOR COMMUNICATING THEREOF - The present invention relates to a communications system and a telecommunication method thereof. In the communications system of the present invention, a communications terminal decides a precoding matrix index, in the reception of a pilot signal through a specific downlink channel, examining a channel quality information of the downlink channel according to the decided precoding matrix index, and transmitting a feedback information including the decided precoding matrix index and the examined channel quality information to a serving base station. In the communications system of the present invention, the serving base station decides a priority factor by using the examined channel quality information, in the reception of the feedback information, compares the decided priority factor with other priority factor, when receiving a backhaul information including the other priority factor from the neighboring base station. As a result of the comparison, a priority is given to a higher priority factor such that a base station having the priority suggests the use of precoding matrix to the neighboring base station.
|Method of Minimizing Feedback Overhead Using Spatial Channel Covariance in a Multi-Input Multi-Output System - Disclosed is a method for minimizing feedback overhead in a multi-input multi-output (MIMO) communication method using multiple transmission and reception antennas. In particular, a method for minimizing feedback overhead in a multi-input multi-output (MIMO) communication system by using spatial channel covariance, as explicit channel status information (CSI) feedback method is disclosed.
|DIGITAL PHASE DETECTOR AND DIGITAL PHASE-LOCKED LOOP - According to one embodiment, a digital phase detector includes a chain of delay devices configured to receive a reference signal through a first stage and delay the reference signal at each stage. The phase detector includes a sampler group configured to include a first sampler samples a first signal of N-phase input signals (N is an integer of at least 2) in accordance with the reference signal and a second sampler samples a second signal of N-phase input signals which lags behind the first signal in phase by 2π/N in accordance with an output signal from the first stage of the chain of delay devices. The phase detector includes a detection circuit configured to detect a time difference between an edge of the reference signal and an edge of the first signal based on sampled signals from the sampler group to convert the time difference into a phase difference.
|RECEIVER, INTEGRATED CIRCUIT, RECEIVING METHOD, AND PROGRAM - A receiver includes a demodulator that demodulates a modulation wave modulated according to orthogonal frequency division multiplexing (OFDM). The demodulator includes an interference wave detector that detects that received modulation wave includes interference wave when received power of each sample of the received modulation wave exceeds a threshold, and upon the detection, executes replacement processing of replacing a received signal exceeding the threshold with a predetermined value, a first interference wave power estimation unit configured to estimate interference wave power included in an OFDM symbol included in the received modulation wave on the basis of the number of samples that have been subjected to the replacement processing, and a demodulated data generator that demodulates the received modulation wave by executing demodulation processing of demodulating the received modulation wave that has been subjected to the replacement processing on the basis of the interference wave power.
|DETECTOR AND METHOD FOR DETECTING AN OSCILLATORY SIGNAL AMONG NOISE - A signal detector is configured to detect a signal of interest in a received signal. The received signal may comprise noise. The signal of interest is oscillatory at least during one or more time segments. The signal detector comprises a frequency discriminator arranged to determine an instantaneous frequency of the received signal, an evaluator arranged to determine an amount of change of the instantaneous frequency during a test interval, and a comparator arranged to determine whether the amount of change is below a given threshold. The signal of interest may be digitally modulated. In this case the test interval may be shorter than the duration of one data bit in the signal of interest. In a related aspect, a signal transmission system comprises a signal generator for generating a signal of interest and a signal detector for detecting the signal of interest in a received signal. A method of detecting a signal of interest in a received signal is also proposed.
|IMPEDANCE MEASUREMENT IN AN ACTIVE RADIO FREQUENCY TRANSMITTER - A transmitter and method for determining impedance measurement in an active radio frequency transmitter of an antenna are provided. Voltage and current samples are obtained from a modulating signal delivered to an antenna. The voltage and current samples are converted from analog to digital format, and decimation occurs to reduce the number of samples. Complex demodulation is performed of each of the voltage and current samples to baseband levels and decimation of the voltage and current samples is performed to reduce the number of samples. An impedance estimate can then be estimated from the voltage and current samples.
|DUAL SQUELCH DETECTORS AND METHODS FOR LOW POWER STATES - Apparatus having corresponding methods comprise: a first squelch circuit configured to detect possible squelch signals in a communication signal; and a second squelch circuit configured to i) operate in a low-power state responsive to the first squelch circuit detecting none of the possible squelch signals in the communication signal, and ii) operate in a high-power state responsive to the first squelch circuit detecting one of the possible squelch signals in the communication signal.
|WIRELESS COMMUNICATION SYSTEM WITH IMPROVED AUTOMATIC GAIN CONTROL - A wireless communication device is disclosed that includes an automatic gain controller capable of accurately adjusting gain of a received signal. The received signal includes a plurality of symbols, including pilot symbols that each includes at least one pilot tone, and data symbols that do not include any pilot tones. A power of a pilot symbol is determined, and a power of a data symbol is determined. The determined data symbol power is then scaled by a scaling factor (that depends on various system parameters) and is subtracted from the determined pilot symbol power to provide an estimate of a power of the pilot tones within the signal. From the estimated pilot tone power, the automatic gain controller can accurately determine a preferred gain for amplifying future frames of the received signal.
|METHOD AND ARRANGEMENT FOR ASYNCHRONOUS RSRP MEASUREMENT IN AN LTE UE RECEIVER - In 3GPP LTE, user equipment must be able to report reference signal received power (RSRP) measurement to the serving cell's base station. A low-complexity method for asynchronous RSRP measurement in an LTE user equipment receiver is provided which comprises frequency shifting the received signal so that the upper or lower half band becomes centered around the DC frequency; decimating the received signal to a width of n·2
|PILOT-BASED TIME OFFSET ESTIMATION APPARATUS AND METHOD - The present invention provides a pilot-based timing offset estimation apparatus and method. The timing offset estimation apparatus includes: a pilot bit channel estimation module, configured to acquire pilot bit frequency-domain channel estimation values of target users through calculation on respective sub-carriers of the target users according to received frequency-domain demodulation reference symbols and local frequency-domain demodulation reference symbols; and a timing offset estimation module, configured to respectively perform timing offset estimation for each target user by using phase differences among the pilot bit frequency-domain channel estimation values on the respective sub-carriers. The present invention performs timing offset estimation for multiple users on the basis of the received pilot sequences, therefore provides more accurate measurement values for timing offset compensation and timing offset reporting, so as to reduce the influence of the timing offset on the receiver performance.
|PROGRAMMABLE ENGINE HAVING A RECONFIGURABLE ACCELERATOR DATA PATH FOR TESTING AND CALIBRATION OF ANALOG FRONT ENDS IN RADIO DEVICES - Briefly, in accordance with one or more embodiments, a radio device comprises an analog front end comprising a radio to transmit and/or receive radio-frequency signals, and a programmable engine coupled to the analog front end. The programmable engine is capable of being programmed to perform one or more tests on the analog front end and includes a reconfigurable data path reconfigurable by the programmable engine to perform one or more tests on the analog front end.
|TEST CIRCUIT - A test circuit may include an analog signal generator having an output and configured to generate an analog output signal at the output in accordance with a timing parameter; an analog-to-digital converter (ADC) having an input connected to the output of the analog signal generator, and an output and configured to generate a first digital output signal dependent on the analog signal; and a configurable digital signal generator comprising an output and configured to generate a second digital output signal in accordance with the timing parameter at the output.
|NEAR-FIELD MIMO WIRELESS TEST SYSTEMS, STRUCTURES, AND PROCESSES - Systems, processes, and structures allow enhanced near-field testing of the uplink and/or downlink performance of MIMO wireless devices (DUT), such as for any of product development, product verification, and/or production testing. Signal channels may preferably be emulated to test the performance of a device under test (DUT) over a range of simulated distances, within a near-field test environment. An enhanced process provides automated testing of a DUT over a wireless network, e.g. such as but not limited to a WLAN. The enhanced MIMO channel emulator may preferably be operated over a high dynamic range.
|METHOD AND APPARATUS FOR IMPLEMENTING SIGNAL QUALITY METRICS AND ANTENNA DIVERSITY SWITCHING CONTROL - A method for detecting the digital quality of a radio signal includes: receiving a radio signal including a digital portion modulated by a series of symbols each including a plurality of samples; computing correlation points between endpoint samples in cyclic prefix regions of adjacent symbols; and using the correlation points to produce a digital signal quality metric. Receivers that implement the method are also provided.
|METHOD, APPARATUS, COMPUTER PROGRAM AND COMPUTER PROGRAM DISTRIBUTION MEDIUM FOR A COMMUNICATION RECEIVER - The invention relates to an apparatus comprising, a sampler configured to receive and sample a signal for producing signal samples; a first configured to receive or determinate a scaling factor for a reliability factor and to determine power or energy of an input signal of an interference canceller; a generator configured to generate an estimated replica of a transmitted desired signal by using the signal samples; a residual processor configured to subtract the estimated replica from the input signal of an interference canceller for generating a residual signal and to determine power or energy of the residual signal; and a divider configured to divide the power or energy of the residual signal by the power or energy of the input signal of an interference canceller and a multiplier configured to multiply a result of the division by the scaling factor of a reliability factor.
|METHODS AND SYSTEMS FOR TRANSMITTING SIGNALS DIFFERENTIALY AND SINGLE-ENDEDLY ACROSS A PAIR OF WIRES - Provided herein are systems and methods for transmitting signals across a pair of wires. In accordance with specific embodiments, a differential signal is transmitted across the pair of wires during one period of time, and two single-ended signals are transmitted across the same pair of wires during another period of time. Low voltage differential signaling (LVDS) can be used to transmit the differential signal across the pair of wires. In contrast, non-differential signaling can be used to transfer the two singled-ended signals across the same pair of wires.
|APPARATUS, METHODS, AND ARTICLES OF MANUFACTURE TO PREDICT VECTORED DIGITAL SUBSCRIBER LINE (DSL) PERFORMANCE GAINS - Apparatus, methods and articles of manufacture to predict vectored digital subscriber line (DSL) performance gains are disclosed. A disclosed example method includes determining a model coefficient of a noise-to-margin ratio (NMR) model from performance data measured for a DSL subscriber loop prior to provisioning of vectoring for the DSL subscriber loop, computing, using the model coefficient, a first NMR value with disturbers enabled and a second NMR value with disturbers disabled, and estimating an expected vectoring performance gain for the DSL subscriber loop based on the first and second NMR values.
|DIGITAL SUBSCRIBER LINE (DSL) ACCESS MULTIPLEXER WIRING VALIDATION - An example method involves electrically coupling first and second nodes of a device to a port of a digital subscriber line access multiplexer (DSLAM) and to a first end of a communication circuit. The communication circuit facilitates electrical coupling of the port of the DSLAM to a central office switch at a second end of the communication circuit. A signature circuit is electrically coupled between the first and second nodes to generate a signature signal in response to a test signal injected onto the communication circuit at a second end of the communication circuit. The signature signal has a magnitude substantially proportional to the test signal. First and second conductors of the communication circuit are electrically coupled to respective ones of the first and second nodes. Third and fourth conductors of the port of the DSLAM are electrically coupled to respective ones of the first and second nodes.
|APPARATUS AND METHOD FOR ENVELOPE DETECTION - An apparatus and a method are described for envelope detection used in fields including voice processing, image processing, data communication, and energy/data transmission. The apparatus and the method for envelope detection eliminate a carrier component from a modulated signal by performing a square-sum operation between two adjacent sampling signals among signals sampled from the modulated signal. The apparatus and the method detect an envelope of the modulated signal from the modulated signal in which the carrier component is eliminated.
|METHOD AND DEVICE FOR GENERATING AND MAPPING CHANNEL STATE INFORMATION REFERENCE SIGNAL SEQUENCE - The present invention provides a method and device for generating and mapping a Channel State Information Reference Signal (CSI-RS) sequence, and the method includes: generating a pseudo-random sequence according to a pseudo-random sequence initial value, performing a Quadrature Phase-Shift Keying (QPSK) modulation on the pseudo-random sequence, and obtaining a first CSI-RS sequence according to maximum bandwidth of system; and cutting the first CSI-RS sequence according to the actual bandwidth of the system, obtaining a second CSI-RS sequence, and mapping the second CSI-RS sequence to a time frequency location of a CSI-RS antenna port. The CSI-RS reference signal sequence can be generated or obtained respectively at the UE terminal and eNB terminal in accordance with the stated methods for generating and mapping the reference sequence according to known parameters by the present invention, so that the calculated CSI-RS sequence can be utilized to measure the channel at the UE terminal.
|SIGNAL PROCESSING METHODS, DEVICES AND SYSTEMS IN BONDING-DSL - In the field of communication, this application discloses a signal processing method, device, and system of bonded DSL channels. A signal processing method of bonded DSL channels: sending a pilot sequence to a receiving end through bonded channels; receiving, through the bonded channels, clipped error sample fragments returned by the receiving end, where the receiving end constructs a clipped error sample according to an error of a received signal and fragments the clipped error sample to acquire the clipped error sample fragments; aggregating the received clipped error sample fragments into a clipped error sample; and calculating a pre-encoding coefficient according to the pilot sequence and the aggregated clipped error sample, where the pre-encoding coefficient is used to perform pre-encoding processing on a signal before the signal is sent.
|METHOD FOR DETERMINING HYBRID DOMAIN COMPENSATION PARAMETERS FOR ANALOG LOSS IN OFDM COMMUNICATION SYSTEMS AND COMPENSATING FOR THE SAME - In a transmit/receive system, the carrier frequency offset (CFO), I/Q imbalance, and DC offset (DCO) can cause serious signal distortions. These analog losses can be compensated for individually or in combination of any two of them by following various methods that have been suggested. However, there have suggested no methods of simultaneously compensating, for these three types of losses that occur in actual devices at the same time. The present invention suggests a novel pilot signal that has a cyclic signal portion and a portion of two equally spaced continual signals. The invention provides a method for compensating for the CFO, I/Q imbalance, and DCO by simultaneously performing the time domain compensation and the channel estimation using those signal portions. The method also compensates for the I/Q imbalance and the channel response on the transmitter side in the OFDM scheme.
|METHODS AND APPARATUS FOR DIRECT SYNTHESIS OF RF SIGNALS USING DELTA-SIGMA MODULATOR - Methods and apparatus are provided for direct synthesis of RF signals using a delta-sigma modulator. An RF signal is synthesized from an input signal by quantizing the input signal using a quantizer, such as a one bit quantizer; determining a quantization error associated with the quantizer; generating an error prediction value using an error predictive filter, wherein the error predictive filter comprises one or more filter zeroes on a unit circle for one or more desired frequencies of f
|Peak detector having extended dynamic range - According to one embodiment, a peak detector having extended dynamic range comprises a first differential output coupled to a supply voltage of the peak detector by a first load and coupled to ground by first and second switching devices, and a second differential output coupled to the supply voltage by a second load and coupled to ground by third and fourth switching devices. The control terminals of the first, second, third, and fourth switching devices receive a common bias voltage, and the respective first and second control terminals are configured as differential inputs of the peak detector. In some embodiments, corresponding first power terminals of the first and second switching devices share a first common node further shared by the first differential output, and corresponding first power terminals of the third and fourth switching devices share a second common node further shared by the second differential output.
|Communication Apparatuses and Wireless Communications Modules - A communication apparatus having a first and second wireless communications modules is provided. The first wireless communications module includes a receiving unit receiving RF signals from an air interface, a signal processing module performing frequency down conversion on the RF signals to generate baseband signals according to a clock signal, and a processor processing the baseband signals. The processor further detects an ON/OFF status of the second wireless communications module to obtain a detection result and compensates for frequency drift of the clock signal according to the detection result.
|ADAPTIVE COVARIANCE MATRIX CONDITIONING FOR A LINEAR EQUALIZER WITH RECEIVE DIVERSITY - A method of wireless communication with improved performance employs an equalizer receiver with multiple receive antennas. Equalizer taps for linear filters of the equalizer receiver are generated by determining a conditioned covariance matrix of a first data path and a second data path based on a first gain (g
|COMPLEX ADAPTIVE PHASE DISCRIMINATOR - A Complex Adaptive Phase Discriminator (PD), as presented in some concepts of the present disclosure, is an adaptive filter that accurately estimates the instantaneous frequency of a dynamic complex signal. The PD can demonstrate accurate instantaneous frequency estimation and rapid convergence in dynamic complex signal environments, even when the frequency of its input may change rapidly. A direct PD architecture can estimate the instantaneous frequency of a complex primary signal, iteratively adapting a phase of a complex exponential by minimizing the mean squared error of a complex error signal. Instantaneous frequency can be directly estimated from the phase of the complex exponential. In contrast, an indirect PD architecture can estimate the instantaneous frequency of a complex primary signal, iteratively adapting a complex coefficient by minimizing the mean squared error of a complex error signal. Instantaneous frequency can be indirectly estimated by extracting the phase of the complex coefficient.
|MULTI-RANGE OBJECT LOCATION ESTIMATION - Estimating the impulse response of a channel by providing an initial signal (
|DIGITAL COMMUNICATIONS TEST SYSTEM FOR MULTIPLE INPUT, MULTIPLE OUTPUT (MIMO) SYSTEMS - A digital communications test system and method for testing a plurality of devices under test (DUTs) in which multiple sets of a single vector signal analyzer (VSA) and single vector signal generator (VSG) can be used together to perform error vector magnitude (EVM) measurements for one or more DUTs in parallel, including one or more of composite, switched and multiple input multiple output (MIMO) EVM measurements. This allows N pairs of a VSA and VSG to test N DUTs with N×N MIMO in substantially the sane time as a single VSA and VSG pair can test a single DUT, thereby allowing a substantial increase in testing throughput as compared to that possible with only a single VSA and VSG set.
|MOBILE WIRELESS TERMINAL, A METHOD OF MEASURING SIGNAL STRENGTH OF A RECEIVED SIGNAL, AND A METHOD OF SEARCHING FOR A BASE STATION - A mobile wireless terminal includes a wireless receiving part configured to receive a wireless signal from a base station which belongs to a mobile communication system using a time-frequency conversion for baseband processing; a received signal processing part that includes a time-frequency converting circuit and is configured to process the wireless signal; a setting part configured to successively set central frequencies within regions, wherein a frequency band that the mobile communication system uses is divided into the regions having a predetermined bandwidth; and a received signal strength measuring part configured to measure signal strength of received signals over the regions of the frequency band that the mobile communication system uses based on time-frequency conversion results from the time-frequency converting circuit, the time-frequency conversion results being obtained for the respective regions using the respective central frequencies set by the setting part.
|APPARATUS AND METHOD FOR SAMPLING AND RECONSTRUCTION OF WIDE BANDWIDTH SIGNALS BELOW NYQUIST RATE - A method and system of reconstructing data signals from one of incomplete measurements comprising a receiver for receiving data signals, an ADC system operatively connected to the receiver that digitizes the received data signal at a slower rate than the Nyquist rate to obtain sparse measurements; first and second dictionaries comprising a plurality of time shifted responses recovered from the data signal; the first dictionary comprising time shifted versions of the previously observed data signals which are sampled at or above the Nyquist minimum sample rate; the second dictionary comprising time shifted versions are sampled below the Nyquist minimum, and at least one processor for reconstruction of the waveform signals by transforming the sub-Nyquist digitized output using the first and second dictionaries to produce the data signal.
|Asynchronous Calibration for Eye Diagram Generation - Techniques are disclosed for asynchronous calibration for eye diagram generation. For example, a method for calibrating a process for generating a data eye associated with a received signal comprises the following steps. Samples of the received signal are obtained for a first unit interval using a first data latch and a roaming latch. A delay offset is determined between the first data latch and the roaming latch by comparing at least one sample obtained using the first data latch and at least one sample obtained using the roaming latch, wherein the delay offset determined by the comparison is used to calibrate the process for generating the data eye associated with the received signal. A similar comparison may be done for a second data latch and used to calibrate the process. The method is able to find the accurate position of each data latch with respect to the roaming latch so as to improve the accuracy of data decoding in a digital receiver, i.e., provide receiver optimization.
|HD RADIO RECEIVER AND AUTOSTORE CONTROL METHOD - An HD radio receiver includes a storage unit for carrying out tuning at a time when autostore is activated and for storing broadcasting station data about a terrestrial digital radio broadcast received by the tuning, a reception quality detecting unit for detecting reception quality of the radio broadcast received, and a control unit for deciding the number of broadcast programs of multicasting that broadcasts a plurality of programs on a single frequency from the terrestrial digital radio broadcast received and for registering in the storage unit broadcasting station data with a greater number of decided broadcast programs in preference to broadcasting station data with better reception quality detected by the reception quality detecting unit.
|SYMBOL TIMING ACQUISITION USING EARLY-LATE INTERPOLATION - Symbol timing acquisition is described for a wireless broadband signal received at a user terminal from a gateway via a satellite. In-phase and quadrature channels of the wireless signal may each be sampled at a rate of one sample per symbol. The samples may be interpolated to generate an early interpolation and a late interpolation for each of the samples. A difference measurement is obtained between the early interpolation and the late interpolation for a set of the samples. A number of the difference measurements may be averaged, and symbol timing may be modified based on the average. This process may be continued on an iterative basis to acquire symbol timing.
|RECEIVING CIRCUIT - A receiving circuit includes: an analog-to-digital converter to convert an input signal in a certain bandwidth to a digital signal; a Fourier transformer to convert the digital signal from a time-domain signal to a frequency-domain signal; a band-elimination filter to extract an interference wave signal from the time-domain signal; and a filter control circuit to measure frequency characteristics of the interference wave signal so that the attenuation characteristics of the band-elimination filter has a attenuation characteristics opposite to the frequency characteristics in a direction.
|METHOD FOR BEAMFORMING TRANSMISSIONS FROM A NETWORK ELEMENT HAVING A PLURALITY OF ANTENNAS, AND THE NETWORK ELEMENT - In one embodiment, the method includes receiving a pilot signal from a terminal at a target antenna of the plurality of antennas of the network element, determining an uplink channel estimate for the target antenna based on the received pilot signal, and obtaining a calibration coefficient associated with the target antenna. The calibration coefficient is based on a channel estimate between the target antenna and a different one of the plurality of antennas. The method further includes beamforming a transmission to the terminal using at least the target antenna based on the determined uplink channel estimate and the obtained calibration coefficient.
|PEAK POWER SUPPRESSING CIRCUIT AND COMMUNICATION DEVICE HAVING THE SAME - An object of the present invention is to provide a peak power suppressing circuit
|Method and Apparatus for Bandpass Digital to Analog Converter - Systems and methods for providing a mechanism by which digital signals can be converted to analog signals with an efficient structure that reduces the number of filters required by providing a mechanism for cancelling images that would otherwise be generated By adjusting three parameters in the system, a selection can be made as to whether to generate upper sidebands, lower sidebands and in which direction the envelope of the output from the system will be skewed.
|Detection of Low-Amplitude Echoes in a Received Communication Signal - A system and method for identifying minor echoes present in an input signal in the situation where a set of major echoes has already been identified from the input signal. The method includes: computing a spectrum F corresponding to a sum of the major echoes; computing a weighted power spectrum S
|COMMUNICATIONS EFFECTS IN NETWORK SIMULATIONS - Real-time, high fidelity communication effects are simulated. A transmitter in a platform simulation is requested to send a surrogate message to a receiver in the platform simulation. Communications effects are computed in response to the message, and the communications effects are saved for later use. When a future communication event involving the transmitter and receiver occurs, the saved effects are used to simulate the communication effects for that event.
|PULSE SIGNAL RECEIVING APPARATUS AND TRANSMISSION SYSTEM - A pulse signal receiving apparatus may include a reception unit that receives a pulse signal modulated by a double-edge modulation scheme, a measurement unit that measures an edge interval of the pulse signal, which has been received by the reception unit, a detection unit that detects a deviation of the edge interval, which has been measured by the measurement unit, for a pulse-width reference value indicating a reference value of a width of the pulse signal, a correction unit that corrects the edge interval, which is to be measured next by the measurement unit, by using the deviation, which has been detected by the detection unit, and a decoding unit that decodes the pulse signal, of which the edge interval has been corrected by the correction unit, so as to output a digital signal.
|METHODS AND APPARATUS FOR REDUCING THE AVERAGE-TO-MINIMUM MAGNITUDE RATIO OF COMMUNICATIONS SIGNALS IN COMMUNICATIONS TRANSMITTERS - A communications transmitter configured to reduce the average-to-minimum magnitude ratio (AMR) of a communications signal includes a symbol mapper, a pulse-shaping filter, an AMR reduction circuit, and a modulator. The symbol mapper operates to generate a sequence of symbols from a binary-source data stream containing a message to be transmitted, and the pulse-shaping filter generates a baseband signal based on the sequence of symbols. The AMR reduction circuit is configured to compare a magnitude of a local minimum of samples of the baseband signal to various magnitude threshold levels, and to modify the baseband signal in one of two manners depending on the relationship of the magnitude of the local minimum and the various threshold levels. Finally, the modulator operates to modulate a carrier signal based on the modulation information contained in the modified baseband signal.
|FEEDBACK SCHEME FOR MULTI-CELL INTERFERENCE MITIGATION CONSIDERATION LEGACY MOBILE USERS - The present invention relates to a Multi-Input Multi-Output (MIMO) communication system and more particularly, to a method for precoding matrix index (PMI) restriction/recommendation in a multi-cell wireless communication system. A method of codebook based precoding matrix index (PMI) feedback considering legacy mobile stations in a multi-cell wireless communication system comprises measuring a channel from at least one neighboring base station generating interference with a signal received from a serving base station; determining a first PMI in which the interference is maximized from PMIs included in a first codebook, wherein the first PMI is determined based on the measured channel; determining a first PMI group including PMIs having high correlation to the first PMI from the PMIs included in the first codebook; determining a second PMI in which the interference is maximized from PMIs included in a second codebook, where in the second codebook is for the legacy mobile stations; determining a second PMI group including PMIs having high correlation to the second PMI from the PMIs included in the second codebook; and transmitting feedback information including the first PMI, a first subset bit indicating the first PMI group, the second PMI and a second subset bit indicating the second PMI group to the serving base station.
|ENHANCED SPATIAL MODULATION - A method of spatial modulation and associated transmission apparatus, receiver apparatus, computer program product and system for identifying a transmitter element within a transmission array of at least two transmitter elements, wherein a signal is transmitted by one active transmitter element at a time over a channel to a receiver. Power is allocated to the transmitter elements, wherein the power is allocated differently between at least two transmitter elements. The transmitted data is received at the receiver. The location of the active transmitter element is detected using knowledge of the power allocated to the transmitter elements.
|NOISE ESTIMATION FILTER - A noise estimation filter for an orthogonal frequency-division multiplexed (OFDM) system can include a filter bank module, a coefficient squaring module, and a summing module. The filter bank module can multiply a unitary vector by an OFDM signal vector to generate scalar products of the OFDM signal vector. The coefficient squaring module can square the scalar products and weight the scalar products to generate a plurality of weighted single estimates. The coefficient squaring module can include a squaring module for squaring the scalar product to generate a plurality of single estimates and a coefficient multiplication module for weighting each of the single estimates with a noise coefficient forming a plurality of weighted single estimates. The summing module can sum the weighted single estimates to generate a noise and interference power estimate.
|TIME ERROR ESTIMATION FOR DATA SYMBOLS - The invention relates to a method and a system for estimating a symbol time error in a broadband transmission system, comprising: determination a timing error signal of an input-signal of a discrete Fourier-transformation block (
|Method and Device for Testing a Mobile Station's Capability of Processing at Least One Second Channel and Communication System Comprising Such Device - A method and a device are provided for testing a mobile station's capability of processing at least two channels in a resource unit is provided, wherein a base station provides a test message to the mobile station; wherein the mobile station's capability of processing the at least two channels is determined based upon the mobile station's feedback. Further, a communication system comprising such a device is suggested.
|Method and apparatus for regaining watermark data that were embedded in an original signal by modifying sections of said original signal in relation to at least two different - Every watermarking processing needs a detection metric to decide at decoder side whether audio signal content is marked, and which symbol is embedded inside the audio signal content. The invention provides a new detection metric that achieves a reliable detection of watermarks in the presence of additional noise and echoes. This is performed by taking into account the information contained in the echoes of the received audio signal in the decision metric and comparing it with the corresponding metric obtained from decoding a non-marked audio signal, based on calculating the false positive detection rates of the reference sequences for multiple peaks. The watermark symbol corresponding to the reference sequence having the lowest false positive error is selected as the embedded one.
|Receiver with On-Demand Linearity - Aspects of a method and system for on-demand linearity in a receiver are provided. In this regard, in a receiver such as on-chip receiver, a strength of a signal received by one or more antennas may be measured and linearity of the receiver may be controlled in response to the measured signal strength. The linearity may be controlled based on signal strength of in-band and/or out-of-band signals and by configuring component(s) of the receiver. Exemplary components may comprise one or more filter, amplifier, mixer, analog-to-digital converter, feedback loop, and equalizer and/or post corrector. Linearity may be increased, by switching one or more feedback loops and/or an equalizers and/or post correctors into a signal path of the receiver. Power consumption may be decreased, at the expense of reduced linearity, by switching one or more feedback loops and/or an equalizers and/or post correctors out of a signal path of the receiver.
|Method and System for Communication Channel Characterization - In accordance with the present invention, a method of processing a signal is described that includes receiving a signal having an encoded digital packet, wherein the digital packet includes packet data and a packet frame, wherein the packet frame includes a common digital signal that is common to each one of a plurality of digital packets. The method further includes sampling a signal associated with the received signal to provide a sampled signal. The method further includes performing a channel characterization by contrasting a signal representative of the sampled signal with a signal representative of the common digital signal. A corresponding system is also described.
|METHOD, APPARATUS, AND SYSTEM FOR MEASURING ASYMMETRIC DELAY OF COMMUNICATION PATH - A method for measuring the asymmetric delay of a communication path includes: sending, by a first node, a first delay measurement message to a second node whose local clock is synchronized with the first node; receiving, by the first node, a second delay measurement message sent by the second node; calculating, according to time when the first delay measurement message is sent by the first node and time when the second node receives the first measurement message, a communication path delay in a direction towards the second node; calculating, according to time when the second node sends the second delay measurement message and time when the second measurement message is received by the first node, a communication path delay in a direction leaving the second node; and obtaining a measured value of the asymmetric delay of the communication path according to the communication path delays in the two directions.
|Controllable Frequency Offset for Inphase and Quadrature (IQ) Imbalance Estimation - Embodiments of user equipment and methods for determining IQ imbalance parameters are described. In some embodiments, a method for determining in-phase (I) and Quadrature (Q) imbalance (IQ imbalance) parameters based on a known signal in a dual-carrier receiver using at least one controllable frequency offset includes receiving a known signal modulated onto a first radio frequency (RF) carrier frequency and a second RF carrier frequency different than the first RF carrier frequency; downconverting the known signal to a baseband signal for the first and second carriers by conversion from the respective RF carrier frequencies to an intermediate frequency (IF) using a common RF local oscillator (LO) and by further conversion from IF to baseband using carrier specific IF LOs, wherein as a controllable frequency offset is used as a part of the conversion from at least one of RF to IF and IF to baseband through the LOs; removing any controllable frequency offset from the baseband signal for the first and second carriers to produce representations of the received signals of the first and second carriers; and deriving IQ imbalance parameters for each representation of the received signals of the first and second carriers using a least square estimate.
|METHODS AND SYSTEMS FOR PRECODER SELECTION ASSISTED BY DEMODULATION REFERENCE SIGNALS (DM-RS) - Systems and methods according to these exemplary embodiments provide for using demodulation reference signals (DM-RSs) to obtain channel state information (CSI) for precoder selection. A method includes: receiving a DM-RS in at least one subframe, determining the CSI from the DM-RS; and using the CSI to perform at least one function.
|ADAPTIVE FREQUENCY SELECTIVE BASEBAND COMMUNICATIONS METHOD USING ORTHOGONAL CODES - An adaptive frequency selective baseband communications method using orthogonal codes includes: a communications testing step of performing communications by using one of a plurality of codes each having a different frequency band; a proper code selecting step of selecting a proper code by using a correlation value of a plurality of codes included in test data transmitted in the communications testing step; a communications performing step of performing communications by using the proper code; and a feedback step of newly selecting a proper code by using the correlation value of the plurality of codes included in the test data transmitted in the communications performing step if a pre-set time duration has lapsed or if a reception error of more than a pre-set reference occurs, and performing the communications performing step again, wherein the test data transmitted in the communications testing step and the communications performing step includes a plurality of codes each having a different frequency band.
|DATA FEEDBACK METHODS AND RELATED APPARATUSES - Embodiments of the present invention disclose data feedback methods and related apparatuses. This enables a beamformer to adjust the communication status according to related channel information about a beamformee no matter whether the number of actual active antennas of the beamformee is larger than or equal to the number of columns set by the beamformer in an NDPA message. The data feedback method according to the embodiments of the present invention includes: acquiring, by the beamformee, the number of columns from the NDPA message; detecting the number of active first spatial streams; comparing the number of first spatial streams with the number of columns, and taking the smaller value obtained from the comparison as the number of second spatial streams required for feedback; and feeding back the number of second spatial streams and spatial stream measurement information about the second spatial streams to the beamformer.
|TRANSMISSION ARRANGEMENT AND METHOD FOR ANALYZING AN AMPLIFIED TRANSMISSION SIGNAL - A transmission arrangement is disclosed having an amplifier which is set up to amplify a transmission signal and to provide it as an amplified transmission signal in differential form, an analysis circuit for determining a property of the amplified transmission signal, and a differential feedback path which is set up to supply the amplified transmission signal to the analysis circuit in differential form.
|PACKET LOSS MITIGATION IN TRANSMISSION OF BIOMEDICAL SIGNALS FOR HEALTHCARE AND FITNESS APPLICATIONS - Certain aspects of the present disclosure relate to a method for compressed sensing (CS). The CS is a signal processing concept wherein significantly fewer sensor measurements than that suggested by Shannon/Nyquist sampling theorem can be used to recover signals with arbitrarily fine resolution. In this disclosure, the CS framework is applied for sensor signal processing in order to support low power robust sensors and reliable communication in Body Area Networks (BANs) for healthcare and fitness applications.
|TRANSMISSION CHARACTERISTIC ADJUSTMENT DEVICE, CIRCUIT BOARD, AND TRANSMISSION CHARACTERISTIC ADJUSTMENT METHOD - A transmission characteristic adjustment device with high reliability in a transmission characteristic that can adjust a circuit before an error occurs and does not generate an error is provided. A transmission characteristic adjustment device that adjusts a transmission characteristic between a transmission element and a receiving element interposing a transmission path, includes: a sight test circuit that is provided on the receiving element side and detects an eye pattern aperture; a margin calculation circuit that calculates a margin with respect to a mask included in the detected eye pattern aperture; a circuit element adjustment circuit that evaluates a setting value of a circuit element of the transmission element or the receiving element having influence on a receiving waveform based on fluctuation of the calculated margin, and changes the setting value of the circuit element of the transmission element or the receiving element based on a result of the evaluation.
|DIGITAL DIAGNOSTICS PARAMETER STORAGE - A method of managing storage of digital diagnostics parameters on a transceiver device may include loading stored digital diagnostics parameters into the system memory, receiving updates to the digital diagnostics parameters in the system memory, and writing the updates to the digital diagnostic parameters in the system memory to persistent memory while providing access to other components to the digital diagnostics parameters by way of the system memory.
|ESTIMATING INTERFERENCE IN MULTI CHANNEL SYSTEMS - A method for estimating interference between a plurality of carrier signals in a multi-channel system including injecting pilot symbols into a first carrier signal and transmitting the first carrier signal, transmitting a second carrier signal, receiving at least the first carrier signal and the second carrier signal, and estimating interference between the received first carrier signal and the received second carrier signal based, at least in part, on measuring the received first carrier signal when a pilot symbol of the first carrier signal is received. A multi-channel communication system including a plurality of transmitters for a plurality of carrier signals, a pilot symbol injector for injecting silent pilot symbols into at least one of the carrier signals, a plurality of receivers for the plurality of carrier signals, and an interference estimator configured to estimate interference between at least two of the plurality of carrier signals based, at least in part, on receiving silent pilot symbols in at least one of the at least two of the plurality of carrier signals. Related apparatus and methods are also described.
|OFDM CHANNEL ESTIMATION SYSTEM AND METHOD COMPONENTS - Channel estimation for high mobility OFDM channels is achieved by identifying a set of channel path delays from an OFDM symbol stream including carrier data, inter-channel interference noise and channel noise; determining the average channel impulse response for the identified set of channel path delays in each symbol; generating a path delay curvature for each channel path delay in each symbol based on stored average channel impulse responses for the identified channel path delays; estimating the carrier data in the symbols in the OFDM symbol stream in the presence of inter-channel interference noise and channel noise from the OFDM symbol steam and the average impulse responses for the identified channel path delays; reconstructing the inter-channel interference noise in response to the path delay curvature, the identified set of channel path delays and estimated carrier data to produce a symbol stream of carrier data and channel noise with suppressed inter-channel interference noise.
|DIGITAL SUBSCRIBER LINE (DSL) NETWORK UPGRADE TOOL - A network upgrade tool identifies at least one new digital subscriber line (DSL) path pre-provisionable elements associated with the at least one new DSL path. The tool provisions the identified pre-provisionable elements prior to transition from at least one existing DSL path to the at least one new DSL path; receives a notification that physical network changes associated with a target digital subscriber line access multiplexer (DSLAM) have been made; and provisions non-pre-provisioned elements following receipt of the notification
|COMMUNICATION APPARATUS AND COMMUNICATION METHOD IN MOBILE COMMUNICATION SYSTEM - The communication apparatus includes: a processing unit
|METHOD FOR DETERMINING A SIGNAL VECTOR AND DETECTION CIRCUIT - A method for determining a signal vector comprising a plurality of components from a received signal vector is provided comprising generating an estimation of the signal vector; determining a channel matrix characterizing the communication channel via which the signal vector was received; carrying out a plurality of determination iterations based on the channel matrix, wherein for each iteration a first set of possible sub-vectors of the signal vector is determined based on a second set of possible sub-vectors for the previous iteration and from the first set of possible sub-vectors, a number of sub-vectors is selected based on the distance of the sub-vectors to the estimated signal vector according to a pre-selected metric to form a strict subset of the first set as the second set of possible sub-vectors for the iteration; determining the signal vector based on a possible sub-vector for the last iteration.
|CALIBRATION SIGNAL GENERATOR - A calibration signal generator for use in a balancing circuit calibration device in a radio receiver, the calibration signal generator comprising: a means of amplifying a clocking signal from a clocking signal generator to provide a first calibration signal; a means of generating a second calibration signal from the clocking signal, the first and second calibration signals being transmissible to a one or more mixing circuits in the balancing circuit calibration device; and a means synchronising the operation of other circuit elements in the balancing circuit calibration device with the clocking signal; characterised in that the clocking signal generator is present in the radio receiver and used therein for other functions.
|INCIDENT AND REFLECTED SIGNAL PHASE DIFFERENCE DETECTION - Embodiments include methods and apparatus for detecting a phase angle between an incident signal and a reflected signal. The apparatus comprises a plurality of phase shifters and additional circuitry. The plurality of phase shifters is adapted to apply first phase shifts to a representation of the incident signal and to apply second phase shifts to a representation of the reflected signal. The additional circuitry, which is operatively coupled to the plurality of phase shifters, is adapted to produce a first indication of a location of a relative phase difference between the incident signal and the reflected signal within a first region of a first reference circle, and to produce a second indication of the location of the relative phase difference within a second region of a second reference circle, wherein the second reference circle is rotated with respect to the first reference circle.
|Method, Apparatus and System for Antenna Calibration - The present invention discloses a method, an apparatus and a system for calibrating antenna, wherein channel transfer functions are obtained for subcarriers on at least one antenna to be calibrated and on a reference antenna, and the obtained channel transfer function of a first subcarrier is filtered by multiplying a symmetry filter with channel transfer functions of said first carrier's neighboring subcarriers, and the filtered channel transfer function is normalized; and a signal carried by the first subcarrier on the antenna to be calibrated is multiplied with the ratio of the filtered and normalized channel transfer function of the first subcarrier on said reference antenna to the filtered and normalized channel transfer function of said first subcarrier to get compensated. This enables to perform joint compensation on a subcarrier basis and thus reduce computation complexity.
|CHANNEL ESTIMATION APPARATUS AND METHOD IN MOBILE COMMUNICATION SYSTEM HAVING DISPERSED PILOT - Provided are a channel estimation method and apparatus in mobile communication system having dispersed pilot. The channel estimation apparatus includes an entire band channel estimation unit and an edge channel estimation unit. The entire band channel estimation unit performs channel estimation on an entire frequency band. The edge channel estimation unit performs channel estimation on an edge region. By separately performing the gating operation of the entire band channel estimation unit and the gating operation of the edge channel estimation unit, a channel frequency response is more accurately calculated even in an edge region.
|Systems and methods for probing wired communication channels - Various systems and methods for probing a communication channel. These systems and methods transmit an error vector probe packet from a first transmitter while a second transmitter is active and transmitting. A network device may receive the error vector probe packet and measure an error vector magnitude based on the received error vector probe packet. Using the error vector magnitude, the network device estimates channel characteristics such as signal-to-noise ratio, data capacity, etc. The transmission can occur when more than one transmitter is active and transmitting. At least some of the other transmitters are active and transmit an analog zero signal, e.g., all digital zeros on the input to the digital-to-analog converter of a network device when an error vector probe packet is transmitted.
|EVALUATION UNIT AND A METHOD FOR DEMODULATION OF OFDM DATA - The present disclosure provides an evaluation unit which includes a central data-processing unit, at least one storage unit and an allocation unit, wherein the allocation unit and the at least one storage unit (
|SIGNAL PROCESSING DEVICE AND SIGNAL PROCESSING METHOD - A signal processing device includes a mixer
|Extension of Physical Downlink Control Channel Coverage - It is provided an apparatus, including observing means configured to observe a first parameter; deciding means configured to decide, based on the first parameter, whether or not an original search space of a downlink control channel of an orthogonal frequency division multiplex technology is to be redefined; and redefining means configured to redefine the original search space, thus obtaining a redefined search space.
|REFERENCE SIGNAL TRANSMISSION METHOD FOR DOWNLINK MULTIPLE INPUT MULTIPLE OUTPUT SYSTEM - A reference signal transmission method in a downlink MIMO system is disclosed. The downlink MIMO system supports a first UE supporting N transmission antennas among a total of M transmission antennas (where M>N) and a second UE supporting the M transmission antennas. The method includes transmitting, by a base station (BS), subframe-associated information which designates a first subframe in which data for the first UE and the second UE is transmitted and a second subframe in which data only for the second UE can be transmitted within a radio frame having a plurality of subframes, and transmitting the first subframe and the second subframe. Reference signals corresponding to antenna ports '0' to 'N−1' of the N antennas are mapped to the first subframe, and reference signals corresponding to antenna ports '0' to 'M−1' of the M antennas are mapped to the second subframe.
|PAPR (PEAK-TO-AVERAGE POWER RATIO) DETERMINING DEVICE AND COMMUNICATION DEVICE - A PAPR determining device includes a detecting unit and a PAPR determining unit. The detecting unit detects a predetermined value's changes, which is a cause of changes in a saturation power of a power amplifier. When the detecting unit detects any change in the predetermined value, the PAPR determining unit determines a PAPR value that corresponds to the saturation power of the power amplifier.
|SAMPLING POINT DETECTION CIRCUIT, TRANSMISSION SYSTEM, PRE-EMPHASIS INTENSITY ADJUSTMENT METHOD, LOGIC ANALYZER, AND EVALUATION METHOD FOR EVALUATING TRANSMISSION PATH - A sampling point detection circuit
|CHANNEL ESTIMATION FILTERING - The disclosed methods and systems for improved OFDM channel estimation filtering take advantage of the presence of highly correlated adjacent subcarriers to reduce the computational intensiveness of channel estimation filtering. Specifically, baseband signals corresponding to a channel are received. The cyclic prefixes of the baseband signals are removed, and the resulting signal is transformed into the frequency domain, and compensated by a first time offset of the baseband receive signal. Subcarrier signals used to transmit the baseband signal are then extracted. Adjacent subcarriers having channel responses highly correlated to the subcarriers of the channel are identified, and the signal is compensated by a second time offset that corresponds to a minimal angle of the autocorrelation function of the subcarrier and adjacent subcarriers. The resulting signal is filtered to produce filtered channel estimates, using a filter having a filter length corresponding to the number of highly correlated subcarriers that were identified.
|COMMUNICATION APPARATUS AND RECEPTION POWER MEASURING METHOD - A communication apparatus includes: a quadrature detection unit 13 for performing a quadrature detection on a baseband OFDM signal and generating a complex OFDM signal; an FFT unit for performing a Fourier transform process on the complex OFDM signal and outputting a complex symbol with respect to each subcarrier; and a reception power calculation unit for obtaining a reception power of a reception signal based on the sum of squares of an in-phase signal and a quadrature signal of the complex symbol of the subcarrier outputted from the FFT unit. The reception power calculation unit includes a table indicating the relationship between the reception power and the sum of squares of the in-phase signal and the quadrature signal of the complex symbol, and obtains the reception power of the reception signal by using the table.
|METHOD FOR TESTING A RADIO FREQUENCY (RF) RECEIVER AND RELATED METHODS - A method for testing a radio frequency (RF) receiver may include measuring a plurality of bit error levels for the RF receiver at a given RF frequency. The method may further include applying a Huber function to the measured plurality of bit error levels to generate a bit error ratio (BER) estimate for the RF receiver. The method would also include using the BER estimate to generate a sensitivity for the RF receiver.
|SYSTEM AND METHODS FOR DETERMINING RADIATED RADIO FREQUENCY (RF) RECEIVER SENSITIVITY - A test method is for determining RF sensitivity of an RF receiver for a plurality of channels extending over a frequency band(s) using an RF source coupled to the RF receiver by an RF communications link. The plurality of channels may include channels having a predictable RF sensitivity and a channel(s) having a non-predictable RF sensitivity. The test method may include measuring an RF sensitivity for one or more of the channels having the predictable RF sensitivity, and generating a partial RF sensitivity function for the channels having the predictable RF sensitivity based thereon. The method may further include measuring an RF sensitivity for the channel(s) having the non-predictable RF sensitivity. Additionally, an overall RF sensitivity function may be generated for the plurality of channels based upon the partial RF sensitivity function, and based upon the measured RF sensitivity for the channel(s) having the non-predictable RF sensitivity.
|Processing of Channel Coefficients of a Network - The present subject matter discloses a system and a method for processing of channel coefficients of networks. In one embodiment, the method includes ascertaining at least one probable synchronization position of a received sequence and projecting, by oblique projection, at least one given noise basis vector spanning a given noise space onto the null space, so as to determine a channel impulse response at the at least one probable synchronization position. Based on a criterion related to the channel impulse response, a synchronization point for the received sequence is identified from the at least one probable synchronization position. The method also includes determining the noise contribution at the synchronization point and determining the noise coefficient of the at least one given noise basis vector based on the noise contribution so as to recover a signal substantially similar to the originally transmitted signal.
|System and Method for Non-Uniform Bit Allocation in the Quantization of Channel State Vectors - A system and method for non-uniform bit allocation in the quantization of channel state vectors is provided. A method for communications node operation includes receiving a bit-allocation profile for use in quantizing channel state information, measuring a communications channel between the communications node and a controller, generating channel state information based on the measurement, computing a bit representation of the channel state information, transmitting the bit representation to the controller, and receiving a transmission from the controller. The computing makes use of quasi-tail-biting trellis decoding, and the computing is based on the bit-allocation policy. The transmission makes use of the channel state information transmitted by the communications node.
|Method and Apparatus for Estimating a Doppler Frequency - A method for supporting wireless communication over a physical channel in a mobile broadband system includes providing an estimate of the channel and obtaining a channel autocorrelation function of a channel impulse response of the channel. The method also includes expressing the channel autocorrelation function as a zero order Bessel function and applying Taylor expansion to the zero order Bessel function. Additionally, the method includes performing derivation of the channel autocorrelation function to obtain an estimate of the maximum Doppler frequency and using the obtained estimate of the maximum Doppler frequency to compensate for a current Doppler effect in a receiver receiving the signals.
|METHOD AND APPARATUS FOR DIGITALLY PROCESSING OFDM SIGNALS FOR RADAR APPLICATIONS - The present invention relates to a method and also a device for digitally processing OFDM signals which are emitted by a transmission apparatus with modulation symbols as information carriers, reflected at one or a plurality of objects at least to some extent and received by a receiving apparatus. The modulation symbols are extracted without prior channel equalisation from the OFDM signals received and the extracted modulation symbols are normalised by a complex division to the respectively transmitted modulation symbol. The radar analysis for determining the distance and/or determining the speed of the objects then takes place on the basis of the normalised modulation symbols. With the method and the device, on the one hand, both distance and speed of the objects can be determined independently of one another. On the other hand, the method works very reliably, as it is not influenced by the transmitted information.
|APPARATUS AND METHOD FOR WIRELESS COMMUNICATION - In a wireless communication method, a first wireless communication apparatus transmits through a first wireless resource to a second wireless communication apparatus a first signal generated from a second signal for use in processing performed by the second wireless communication apparatus and a third signal for use in error checking of the second signal. The second wireless communication apparatus detects a second wireless resource to be used in the processing on the basis of the first signal, and performs the processing by using the second signal and the detected second wireless resource. For the detection, a section of the first signal corresponding to the second wireless resource is scrambled, or the first signal is scrambled with a scrambling sequence corresponding to the second wireless resource, or the bit order in at least part of the first signal is changed in a manner corresponding to the second wireless resource.
|POLAR TRANSMITTER AND RELATED SIGNAL TRANSMITTING METHOD - A polar transmitter includes: a processor arranged to convert signals from a specific coordinate system to a polar coordinate system, wherein the signals in the polar coordinate system comprises a phase component and an amplitude component; a PM path configured to have a constant PM group delay, for processing the phase component; an AM path, of which an AM group delay is capable of being determined, for processing the amplitude component; and an adjustable delay circuit, arranged to adjust delay of the signals in the specific coordinate system according to the constant PM group delay and the calibrated AM group delay.
|DIGITAL SYSTEM AND METHOD OF ESTIMATING NON-ENERGY PARAMETERS OF SIGNAL CARRIER - Navigation satellite receivers have a large number of channels, where phase discriminators and loop filter of a PLL operate in phase with data bits and control of numerically controlled oscillator (NCO) carried out simultaneously on all channels. Since symbol boundaries for different satellites do not match, there is a variable time delay between the generation of control signals and NCO control time. This delay may be measured by counting a number of samples in the delay interval. A proposed system measures non-energy parameters of the BPSK-signal carrier received in additive mixture with noise when a digital loop filter of PLL controls NCO with a constant or changing in time delay. A control unit controls bandwidth and a LF order by changing transfer coefficients based on analyzing estimated signal parameters and phase tracking error at a PD output.
|COMMUNICATION DEVICE, A COMMUNICATION SYSTEM AND A COMMUNICATION CONTROL METHOD - Provided is a communication device which can handle variation in transmission power accompanying switching of a modulation system.
|LIN RECEIVER PROVIDING IMMUNITY AGAINST ISO PULSES - A LIN receiver circuit includes filtering circuitry receiving an input signal and producing a filtered signal, a first comparator comparing the filtered signal to a threshold voltage, and a driver block producing the receiver output signal. The receiver circuit further includes an input comparator, signal-adjusting circuitry, and deglitching circuitry. The input comparator detects a low voltage on the input signal, and the signal-adjusting circuitry drives the filtered signal to a particular value to shorten the length of a glitch at the output of the first comparator. Meanwhile, the deglitching circuitry detects and removes the glitch to produce a deglitcher output signal. The deglitcher output signal is received by the driver block, which outputs the receiver output signal, wherein the receiver output signal contains no glitches, and is delayed by no more than 7.5 μs, thus providing immunity to ISO pulses.
|IMPAIRMENT COMPENSATION - A method is provided for compensating for impairment of an electrical signal output from a device under test (DUT), the impairment resulting from an impairment network. The method includes measuring an impaired electrical signal received at an electronic analyzer via the impairment network; applying a coded pulse sequence to the impairment network; estimating an impairment transfer function corresponding to the impairment based on the applied pulse sequence; and correcting the measured electrical signal using the impairment transfer function to determine the electrical signal output from the DUT.
|TECHNIQUES AND SYSTEMS FOR WIRELESS COMMUNICATIONS - Techniques, apparatus and systems for providing radio frequency wireless communications based on time reversal of the channel impulse response of an RF pulse in a transmission channel between an RF transmitter and an RF receiver to enhance reception and detection of an RF pulse at the RF receiver against various effects that can adversely affect and complicate the reception and detection of the RF pulse at the RF receiver.
|SHIELDING FLAW DETECTION AND MEASUREMENT IN QUADRATURE AMPLITUDE MODULATED CABLE TELECOMMUNICATIONS ENVIRONMENT - Signal egress from a shielding flaw in a cable telecommunication system is detected, even where signals carried by the cable telecommunication system are quadrature amplitude modulated signals that statistically resemble broadband noise by generating a marker signal comprising a double side band, suppressed carrier signal in the fringes of contiguous frequency bands and at a power level which cannot cause perceptible interference with signals in those contiguous frequency bands. The separation of the sidebands comprising the marker signal can unambiguously identify the marker signal and can distinguish between different cable telecommunication systems installed in the same geographic area. The marker signal can be additionally coded by varying the frequency and/or amplitude of the modulating signal used to create the marker signal.
|Switching Transistor States to Communicate Faulty Wire in Cable - An electronic device has a transmitter, a microprocessor in communication with the transmitter, a receiver that communicates with the transmitter along a cable using differential signaling, and a transistor. The transistor switches states to communicate a signal to the microprocessor when a wire in the cable is faulty.
|Recursive frequency estimation - A system for receiving signals is set forth. The system includes an open loop frequency offset updating system adapted to receive an input signal. The open loop frequency offset updating system updates a frequency offset recursively, using a real time update value for value Γ(ƒ,N). The system samples the signal and calculates an alternate quantity based on Γ(ƒ,N) to determine a maximum value of the alternate quantity.
|Method and Apparatus for Enhancing the Accuracy of the Estimated Covariance Matrix in Wideband-CDMA Systems - A set of channelization codes to be monitored is divided into two groups. The first group includes those codes for which an associated symbol modulation and transmit-diversity scheme is known. In the second group are those codes that are characterized by an unknown symbol modulation or unknown transmit-diversity scheme. The quality of the transmission of each code is then evaluated, using a metric. The metric in turn is used to determine whether the code should be used in estimating the covariance matrix by correlating the RAKE data corresponding to the code (i.e., by computing a correlation matrix for the code) or by first subtracting the channel estimates from the channel samples before correlation (i.e., by computing a covariance matrix for the code). An impairment covariance matrix is computed from the covariance matrices and correlation matrices so computed.
|System and Method for Determining Channel Loss in a Dispersive Communication Channel at the Nyquist Frequency - The present invention includes receiving a signal from an output of a dispersive communication channel established between a transmitter and a receiver, determining normalized Nyquist energy of the signal transmitted along the dispersive communication channel established between the transmitter and the receiver, and generating a mapping table configured to identify peaking value at or above a selected tolerance level at or near the Nyquist frequency for a signal received by the receiver based on the normalized Nyquist energy.
|SMART FEED LINE AUTOMATION SYSTEM BASED ON 10KV CARRIER COMMUNICATION - An embodiment of the present invention provides a smart feed line automation system based on 10 kV carrier communication. The system monitors smart switches of the line via 10 kV carrier communication, detects smart transformers, and calls up and returns centralized meter-reading information of smart transformer region. Furthermore, the detection of the state of a 10 kV power line may realize real-time monitoring of the temperature, insulating level and change of voltage and current of a 10 kV aerial line and cable line, and realize alarm for an abnormal state and fault information report, so as to rapidly identify, position, isolate and recover the fault.
|SOFT BIT METRIC GENERATION - Soft bit metric generation computational complexity can be reduced by identifying and utilizing only the dominant terms in a reliability calculation such as a logarithmic likelihood ratio (LLR). The dominant terms are those terms for which the signs of the x and y components match those of channel outputs of the channel outputs. One technique for identifying the dominant terms is by determining the most likely transitions from two consecutive channel output samples Values for the dominant terms can be estimated by either the joint reliability of two consecutive samples of the in-phase component (x
|METHOD, PROGRAM PRODUCT, AND TEST DEVICE FOR TESTING BIT ERROR RATE OF NETWORK MODULE - A method for testing Bit Error Rate (BER) of a network module of a communication device includes executing a BER test program to begin a BER test; obtaining a current time and a test data of the BER test program; recording the current time and the test data corresponding to the current time in the test data recording document. The method also determines whether a time interval between the current time and a time when a last test data was recorded is greater than a predetermined value, and if so records a new time and a new test data.
|PROCESS OF SYNCHRONIZATION IN THE TIME AND FREQUENCY DOMAIN OF MULTIPLE EQUIPMENTS IN A TRANSMISSION SYSTEM WITH OFDM MODULATION - A system for determining a frequency error of an orthogonal frequency division multiplexing (OFDM) signal having a first frequency. The system includes a plurality of filters configured to output a plurality of second signals, each of the plurality of second signals corresponding to a respective one of a plurality of different frequency bands of the OFDM signal. Each of the plurality of second signals includes a corresponding synchronization symbol associated with the OFDM signal. A Fourier transform circuit is configured to receive the plurality of second signals from each of the plurality of filters and output the plurality of second signals. The system is configured to determine the frequency error of the OFDM signal based on the synchronization symbols of the plurality of second signals.
|METHOD AND ARRANGEMENT IN A DSL VECTORING SYSTEM - Method and arrangement in a Vectoring Control Entity, VCE, for handling disorderly events in a Digital Subscriber Line, DSL, system. The method involves a number of actions, to be performed when a disorderly event occurs on a line min a vectored group of DSL lines, and the transmission on line m is continued. The method comprises obtaining(
|SECTORIZED BASE STATIONS AS MULTIPLE ANTENNA SYSTEMS - Methods and apparatus for improved utilization of air link resources are discussed in wireless communications systems employing multi-sector base stations and wireless terminals with multiple antennas. Timing synchronization is maintained across the base station sectors, and the same set of tones are used in adjacent sectors. In a sector boundary region, which is typically a high interference region, a wireless terminal is set to a sector pair state and operated in a MIMO mode of operation, communicating with two adjacent base station antenna faces of the same base station concurrently, the two different adjacent base station antenna faces corresponding to different adjacent sectors. Thus, typically high interference sector boundary regions, are converted into high capacity regions by having the sectors coordinated and utilizing MIMO techniques.
|Method and System For Calibrating a Transmitting System - The invention relates to a method and a system for calibrating a transmitting system (
|MEASUREMENT OF IQ IMBALANCE IN A VECTOR MODULATOR - Described are methods of determining imbalance in an IQ modulator. Example methods include applying a set of at least three test signals to the I channel and Q channel to generate an output, then receiving output from a frequency measuring device coupled to the IQ modulator. Some of the set of test signals may be substantially different than other test signals in the set. After the frequency specific output is received, the method measures one or more values and derives the imbalance in the IQ modulator from the measured values. Embodiments also include adjusting parameters of the test signals until a minimum distance is measured. A device is also described, which includes a test signal generator, an output analyzer, and a minimizer structured to cause the test signal generator to generate a set of test signals that cause a distance measured in the output to be a minimum distance.
|COMMUNICATION SYSTEM, COMMUNICATION DEVICE, AND METHOD FOR OPERATING COMMUNICATION SYSTEM - A communication system includes a first communication device and a second communication device that performs power line communication with the first communication device via an electric power line, wherein the first communication device transmits a plurality of times an initial packet signal added with an error detection code in each of reference timing at regular intervals in the vicinity of zero crossing timing. The second communication device determines whether a reception state is good or poor based on a result of the error detection on each of the received initial packet signals, and when the reception state is poor, the second communication device transmits an ACK signal in timing shifted by micro time from the reference timing after receiving the initial packet signal. Then, the first communication device transmits a data packet signal in timing at the regular interval after the timing of receiving the ACK signal.
|WIRELESS COMMUNICATION SYSTEM, WIRELESS COMMUNICATION APPARATUS AND WIRELESS COMMUNICATION METHOD - In a wireless communication system performing wireless communication via a wireless transmission path, a first wireless communication apparatus includes a receiver that receives a wireless signal via a wireless transmission path, a disconnection detector that detects disconnection of a wireless line connected to a second communication apparatus, a modulation controller that selects a modulation scheme, enabling communication under poor conditions in a transmission path, rather than a modulation scheme which has been used in wireless communication, and a transmitter that notifies the modulation scheme selected by the modulation scheme controller to the second wireless communication apparatus. The second wireless communication apparatus includes a receiver that receives the selected modulation scheme from the first wireless communication apparatus, and a transmitter that transmits signals to the first wireless communication apparatus based on the selected modulation scheme which is received by the receiver.
|COMMUNICATION SYSTEM WITH PROACTIVE NETWORK MAINTENANCE AND METHODS FOR USE THEREWITH - A transmitter for use in a cable modem termination system includes a data processing module that generates a plurality of OFDM symbols from a data packet. A probe symbol generator generates a probe symbol, as one of a plurality of probe symbol types. The probe symbol is selectively inserted within the plurality of OFDM symbols, at a pre-defined probe symbol interval.
|SELF-CALIBRATING SIGNAL RECONSTRUCTION SYSTEM - An approach for calibrating a signal reconstruction system. A signal may be input to a low-pass filter. An output of the filter may be converted to a digital signal which goes to a processor which outputs a reconstruction of the signal to the filter. The reconstruction may be based on an expression that maintains the accuracy of the reconstruction. The expression may include information about samples of the input signal and a low value of the reconstruction. The expression may permit initial calibration and then maintenance of the calibration. The calibration may include compensating for inexpensive components of the filter which have values significantly different than indicated values and/or have large drifts over temperature changes.
|METHOD, DEVICE AND SYSTEM FOR CLOCK SYNCHRONIZATION - A method, a device and a system for clock synchronization are provided. The method includes: under a first transfer mode, generating a first receiving timestamp by using a first link, and acquiring a first transmitting timestamp of a master clock device; under a second transfer mode, generating a second transmitting timestamp by using the first link, and acquiring a second receiving timestamp of the master clock device; and acquiring a time difference to the master clock device according to the first receiving timestamp, the first transmitting timestamp, the second transmitting timestamp and the second receiving timestamp, and realizing a clock synchronization with the master clock device by using the time difference. A slave clock device and a master clock device are provided in the embodiments of the present invention, as well as a system for clock synchronization.
|Multi-Channel Active Noise Control System with Channel Equalization - A multiple error filtered-x least mean square (MEFxLMS) algorithm using a channel equalization virtual secondary path for an active noise control/cancellation (ANC) system for treating noise in a Multiple-Input Multiple-Output (MIMO) system. The channel equalization technique equalizes amplitude levels of the estimated response of all primary channels to overcome limitations caused by the frequency dependent property of standard filtered-x least mean square (FxLMS) algorithm, reduce the variation of convergence speed existed in the multiple channels, and improve the overall performance of the control system. The convergence property of the algorithm is analyzed in the frequency domain.
|SIGNAL COMPRESSION APPARATUS AND METHOD FOR DYNAMIC COMPRESSIVE SENSING USING SPARSITY INFORMATION OF INPUT SIGNAL - Disclosed are a signal compression apparatus and method for dynamic compressive sensing, including: a signal input unit configured to simultaneously output an input signal, and generate and output a linear measurement reference signal based on the input signal; a linear transform unit configured to receive the linear measurement reference signal and variably generate a linear measurement matrix value according to the linear measurement reference signal; a signal compressor configured to output a compressed signal for the input signal based on the generated linear measurement matrix value; and a signal processor configured to reconstruct the compressed signal and perform spectrum sensing of the input signal. Accordingly, it is possible to increase signal compression efficiency of compressive sensing and improve signal reconstruction performance by using sparsity information of the input signal, and also by performing signal compression by using a compression matrix suitable for the sparsity information of the input signal.
|METHOD AND APPARATUS OF USING CDD LIKE SCHEMES WITH UE-RS BASED OPEN LOOP BEAMFORMING - A method and apparatus of wireless communication are disclosed. The wireless communication performs pilot signal transmissions using a first precoding matrix for user equipment specific pilot signals, the pilot signal transmissions having a first transmission rank. The wireless communication also performs data transmissions using a second precoding matrix for data when the data transmissions have a second transmission rank less than the first transmission rank, in which the second precoding matrix includes a transformed version of the first precoding matrix. Alternatively, the wireless communication can perform data transmissions using at least two precoding matrices for data when the data transmissions have a second transmission rank less than or equal to the first transmission rank. Accordingly, the precoding matrix used for data is a transformed version of the precoding matrix used for user equipment specific pilot signals.
|Confirmation of Presence of Narrowband Interference By Harmonic Analysis - One or more processing units confirm existence of narrow band interference in a signal by using an estimate f of the frequency, to check for one or more harmonics. In illustrative embodiments, the estimate f is automatically identified as a second harmonic if a predetermined criterion is satisfied by the signal (in the frequency domain) at either of two frequencies namely (A) frequency f/2 and (B) frequency (M−f)/2 and whichever of these two frequencies is stronger is identified as the fundamental frequency. In several such embodiments, the estimate f is automatically identified as a third harmonic if a predetermined criterion is satisfied by the signal (in the frequency domain) at any of three frequencies namely (C) frequency f/3 and (D) frequency (M−t)/3 and (E) frequency (M+f)/3. If the predetermined criteria are not met at all five frequencies (A)-(E) then f is identified as the fundamental frequency.
|Detection and Estimation of Narrowband Interference By Matrix Multiplication - One or more processing units are programmed to select from among M tones in a frequency domain representation of a signal, a set of tones including at least a strongest tone (relative to background noise) and a tone adjacent thereto. From among M complex numbers in the frequency domain representation of the signal, a set of complex numbers are identified and denoted as a vector Z, corresponding to the selected set of tones. Vector Z is then multiplied with each of M columns of a matrix G which is predetermined to identify a sub-resolution maxima in Z. The M products that result from the vector multiplication of Z and G are used to determine and store in memory at least one or both of: (A) a flag indicating presence or absence of narrowband interference in the signal; and (B) an estimate of a frequency of the narrowband interference.
|Methods and Devices for Determining the Impulse Response of Propagation Channels Involving Emitters, Reflectors and Sensors that are Fixed or Mobile - Method for measuring certain parameters of the impulse response of a propagation channel involving emitters and reflectors that are fixed or mobile, so as to detect and determine the parameters regarding the position and kinematics of these emitters and reflectors, or to auto-locate the reception system implementing the invention, in a system comprising N sensors receiving signals from said emitters or from the reflection on said reflectors, and comprising at least the following steps: determination of an ambiguity function which couples the spatial analysis and the delay-distance/Doppler-kinematic analysis, determination of at least one sufficient statistic C(l, m, K) corresponding to the correlation between the known signal s(kTe) corresponding to the complex envelope of the signal emitted and the output of a filter w(l,m) where l corresponds to a temporal assumption (delay-distance, temporal ramp, etc.) and m to a frequency assumption (Dopper-kinematic, Doppler ramp, etc.), determine the values of the pair (l, m) by comparing the value of the statistic for the pair (l, m) with a threshold value.
|SYSTEMS AND METHODS FOR COMBINING VARIABLE BIT RATE DATA STREAMS - Systems and methods for combining variable bit rate data streams are provided. A plurality of data streams may be identified by a service provider system that includes one or more computers. Each data stream may be a variable bit rate data stream. Based upon an analysis of the respective variable bit rates, the service provider system may determine a subset of the plurality of data streams to be combined. The subset of data streams may then be combined and output by the service provider system for transmission to one or more consumer devices.
|TESTING APPARATUS AND METHOD FOR MIMO SYSTEMS - Four (=M) transmission information signals are output from transmission information generating unit to linear transform unit, where they are transformed into synthesis signals by linear transform expressed by multiplication by a 2×4 matrix having complex numbers as elements. Signal processors perform signal processing corresponding to the modulation technique of test target on synthesis signals. On the resultant signals, 2×2 channel processing unit performs 2×2 pseudo channel processing, thereby forming equivalent M×N channels. Parameter setting unit sets information necessary to acquire desired M×N channel characteristics as the synthesis characteristics of linear transform unit and N×N channel processing unit.
|METHODS AND DEVICES FOR ACQUIRING CONTINUOUS PHYSICAL SIGNALS - Provided is a method for acquiring continuous physical signal such as temperature, pressure and the like. The method comprises the following steps: inputting a voltage signal u representing continuous physical signal; obtaining a sampled signal u
|COMMUNICATION CIRCUIT AND ASSOCIATED METHOD FOR CALIBRATING COMMUNICATION CIRCUIT - The present invention provides a method for calibrating a communication circuit. In an embodiment, the method may include: cooperating start of a calibration procedure, and, by the communication circuit, signaling a calibration signal between a test equipment and the communication circuit. The calibration signal may include a plurality of coexisting component signals respectively at a plurality of calibration frequencies. Associated communication circuit is also disclosed.
|SYSTEMS AND METHODS FOR DETERMINING BITLOADING - A method can include calculating an indication of signal quality for a communications channel based on a message from a node over a communications channel of a network. The calculated indication of signal quality can be adjusted based on a prior indication of signal quality to provide an adjusted indication of signal quality. Bitloading for the communications channel can be determined based on the adjusted indication of signal quality.
|Apparatus and method for changing communication mode in multi-antenna system considering channel environment - An apparatus and a method for determining a multi-antenna transmission mode at a base station in a multi-antenna system are provided. The method for determining the multi-antenna transmission mode includes when using a Multiple Input Multiple Output (MIMO) transmission mode as a multi-antenna transmission mode, determining a reference set point; updating a set point for transmit power control of a terminal according to an error occurrence of a signal received from the terminal; determining whether a channel to the terminal is a channel for applying the MIMO transmission mode by comparing the updated set point with the reference set point; and when the channel to the terminal is not a channel for applying the MIMO transmission mode, changing the multi-antenna transmission mode to a fixed transmission mode.
|METHOD FOR CALCULATING CFO AND I/Q IMBALANCE COMPENSATION COEFFICIENTS, COMPENSATION METHOD USING THE SAME, AND METHOD FOR TRANSMITTING PILOT SIGNAL - The OFDM scheme based communication system is currently being put into practical use because of its effective use of frequencies and its enhanced resistance to multipath. However, since the OFDM scheme treats multiplexed signals with overlapped spectra, the orthogonality between carriers are corrupted and the error rate characteristic is degraded in the presence of CFO. Furthermore, since locally oscillated signals different by a phase of π/2 are difficult to obtain in demodulating the I/Q signal, an imbalance is caused between the I/Q signals, resulting in degradation in the error rate characteristic. The invention suggests a novel pilot signal, and a method for analytically determining compensation values for CFO and I/Q imbalance and compensating for those distortions using the resulting values. Furthermore, the invention is applicable not only to the OFDM scheme but also to any protocol that involves pilot signals.
|METHOD FOR DETECTING ABNORMAILTY OF INPUT SIGNAL AND SLAVE STATION FOR USE IN SAME - A management data region including a plurality of pulse-like signals is included in a series of pulse-like signals output from the master station to the common data signal line, and different from a control/monitoring data region including data of a control data signal and data of a monitoring data signal. Further, when data corresponding to a signal level of an input part is larger than a lower limit threshold value and smaller than an upper limit threshold value, an abnormal state is determined to have been occurred, a low sensitivity state of a signal of an input part is detected based on the determination result of the abnormal state, and a signal configuring data indicating the low sensitivity state is superimposed on the management data region.
|SPACE-TIME BLOCK CODING SYSTEMS AND METHODS - Although orthonormal space-time coding matrices provide for optimal communication system performance in that associated correlation matrices include no non-zero off-diagonal elements, unity code rate orthonormal coding matrices are difficult to identify for arbitrary communication network equipment. According to embodiments of the present invention, non-orthonormal space-time coding matrices, for which associated correlation matrices include non-zero off-diagonal elements, are used to encode data symbols. The non-orthonormal space-time coding matrices are more easily determined, and undesirable effects of the non-zero off-diagonal components are reduced by selecting a coding matrix from among a number of such matrices. For example, a particular space-time coding matrix may be selected from a number of generated space-time coding matrices based on a number of non-zero off-diagonal elements or a power of a trace of the associated correlation matrices.
|METHODS AND SYSTEMS FOR DISTINGUISHING A SIGNAL OF INTEREST FROM INTERFERENCE SIGNALS - A method for distinguishing a signal of interest from one or more interference signals in a received analog signal comprises receiving an analog signal at a radio front end, and transmitting the received analog signal to an analog-to-digital converter to sample data in the received analog signal and output a digital signal. A sub-channel Fast Fourier Transform (FFT) is performed on the digital signal, and sub-channel FFT bin magnitudes are averaged over a set period of time to determine a shape of the received signal. The shape of the received signal is compared to one or more signal reference patterns by computing a metric for the shape of the received signal, and computing a metric for the one more signal reference patterns. The computed metrics are then compared to a predetermined threshold value to determine the presence, or lack thereof, of a signal of interest in the received signal.
|IMPAIRMENT COMPENSATION - A method is provided for compensating for impairment of an electrical signal output from a device under test (DUT), the impairment resulting from an impairment network. The method includes measuring an impaired electrical signal received at an electronic analyzer via the impairment network; applying a stimulus signal to the impairment network; estimating an impairment transfer function corresponding to the impairment based on the applied stimulus signal; and correcting the measured electrical signal using the impairment transfer function to determine the electrical signal output from the DUT.
|DECODING A SIGNAL - Method, receiver and computer program product for processing a signal transmitted from a plurality of spatially separated transmit antennas using a Multiple-Input Multiple-Output transmission over a wireless network. The signal is received at a plurality of spatially separated receive antennas, the signal comprising a plurality of data streams and the quality/reliability of each of the data streams in the received signal is determined. Based on the determined quality/reliability of the data streams, a decoding technique is selected to be one of (i) a successive decoding technique for successively decoding data streams in which one of the data streams is decoded and a signal corresponding to said one of the data streams is removed from the received signal prior to decoding further data streams in the received signal, and (ii) a non-successive decoding technique in which each data stream is decoded from the received signal by treating the other data streams as noise in the received signal. The received signal is then decoded using the selected decoding technique.
|METHOD AND APPARATUS FOR AN ADAPTIVE FILTER ARCHITECTURE - A system that incorporates teachings of the subject disclosure may include, for example, a method for identifying a spectral region in a radio frequency spectrum, determining a signal strength of the spectral region, determining a correlation factor by correlating the signal strength of the spectral region, detecting according to the correlation factor interference in the spectral region, generating coefficient data to substantially suppress the interference in the spectral region, configuring a filter according to the coefficient data to substantially suppress the interference in the spectral region and produce a digital filtered signal, and transmitting the digital filtered signal to a base station. Other embodiments are disclosed.
|SIGNAL PROCESSING UNIT EMPLOYING A BLIND CHANNEL ESTIMATION ALGORITHM AND METHOD OF OPERATING A RECEIVER APPARATUS - A receiver apparatus receives a transmit signal through a plurality of transmission channels, wherein each transmission channel is described by its channel vector. A sparseness evaluation unit (
|RECEIVING DEVICEAANM Soma; NamiAACI TokyoAACO JPAAGP Soma; Nami Tokyo JP - A receiving device reduces a frequency of performing AF check per a predetermined amount of time during a reception of a digital broadcast through a hybrid broadcast to less than a frequency of performing AF check per a predetermined amount of time during a reception of an analog broadcast through the hybrid broadcast.
|SELECTION OF WINDOW LENGTH BASED ON MULTIPLE METRICS - Techniques for windowing a transmission are disclosed herein. In one aspect of the disclosure, the length of a window used for windowing may be configurable and determined for a transmission based on a configuration of the transmission. The configuration of the transmission may be determined based on one or more parameters such as a system bandwidth, a bandwidth assigned for the transmission, the location of the assigned bandwidth within the system bandwidth, a modulation type used for the transmission, etc. In another aspect of the disclosure, a preferred length for a window may be determined for each of a number of possible configurations of a transmission. Different possible window lengths may be evaluated for each possible configuration based on one or more performance metrics. For each configuration, a window length that can provide the best performance for that configuration may be selected as a preferred window length for that configuration.
|DEVICE FOR RECEIVING A DIGITAL SIGNAL - The present invention concerns the field of digital signal receivers provided with means of synchronisation with the transmitter and more particularly digital synchronisation means.
|COMMUNICATION APPARATUS - The present invention provides a communication apparatus (RFIC) capable of performing a DC offset correction of an orthogonal modulation unit with a degree of accuracy higher than conventional. The orthogonal modulation unit of the RFIC includes first and second mixers, an adder and first and second switches. The first mixer receives a first local oscillation signal therein through the first switch. The second mixer receives a second local oscillation signal therein through the second switch. During calibration, a DC offset of the first mixer is adjusted in a state in which the first switch is brought to an ON state and the second switch is brought to an OFF state. Further, a DC offset of the second mixer is adjusted in a state in which the first switch is brought to an OFF state and the second switch is brought to an ON state.
|Echo Profile Probe - In an orthogonal frequency division multiplex (OFDM) communication network, a node transmits an echo profile probe to other nodes in the network. The echo profile probe is a message that allows characterization of the unique echo profile through the communication channel between each node pair. The echo profile is used to calculate the cyclic prefix length needed for optimum communication from one node to the other.
|DIGITAL DATA-AIDED FREQUENCY OFFSET ESTIMATION - Techniques are provided herein for digital data-aided frequency offset estimation offering better performance and increased accuracy over existing solutions. These new techniques also allow a trade-off between complexity and accuracy to be performed. The embodiments of the techniques for frequency offset estimation can be used for correction in both feedback and feed-forward control.
|METHOD FOR CHANNEL ESTIMATION - The invention relates to a method of estimating BEM coefficients of the Channel taps of a transmission Channel of an OFDM System having a given pilot arrangement, comprising, at the receiver side of the transmission Channel, the Steps of a) subsampling a received OFDM symbol in the frequency domain into a set of subsequences, b) inverse Fourier transforming each subsequence into a transformed subsequence, and c) estimating Fourier coefficients of a truncated Fourier series expansion model of the Channel taps from the set of transformed subsequences.
|SIGNAL MEASUREMENT DEVICE, SIGNAL MEASUREMENT METHOD, AND RECORDING MEDIUM - In a signal measurement device, a plurality of mixers output a signal having a frequency equal to a difference between two input frequencies, and a single local signal source feeds a common local signal input to the plurality of mixers. A difference measurement unit measures a level and a phase difference between outputs of the plurality of mixers if a common correction signal input is fed to the plurality of mixers, and a level/phase measurement unit measures the level and the phase of the output of the plurality of mixers if inputs of signal to be measured common in frequency are fed to the plurality of mixers. A difference correction unit corrects a measurement result of the level/phase measurement unit based on a measurement result of the difference measurement unit if a common input of signal to be measured is fed to the plurality of mixers.
|METHOD, APPARATUS AND SYSTEM FOR MEASURING LATENCY IN A PHYSICAL UNIT OF A CIRCUIT - In an embodiment, an apparatus includes a counter to count between a start value and an end value according to a local clock signal, a first register to store an output of the counter, a mirror elastic buffer to store samples of the counter output received from the first register, where the mirror elastic buffer is to mirror an elastic buffer of a receiver circuit, and a resolution logic to receive a counter output sample from the mirror elastic buffer and a current counter value output from the counter, and to determine a transit latency for a data element to traverse the receiver circuit based at least in part on the counter output sample and the current counter value. Other embodiments are described and claimed.
|ADAPTIVE TRANSMISSION AND RECEIVING METHOD AND DEVICE IN WIRELESS COMMUNICATION SYSTEM WITH MULTIPLE ANTENNAS - Disclosed is an adaptive transmit and receive method and device in a multiple-antenna wireless communication system. A transmit mode comprises different main transmit modes each of which includes one or both of a sub-transmit mode based on STBC and a sub-transmit mode based on SM. A receiver calculates an STBC performance parameter and a SM performance parameter, and a transmitter uses the parameters to determine a main transmit mode with maximum data rates and select a sub-transmit mode for minimizing power consumption. The transmitter channel-encodes, modulates and antenna-maps input data according to the selected transmit mode, and outputs results to the receiver. The receiver antenna/symbol-demodulates and channel-decodes the received data.
|APPARATUS AND METHOD FOR QUANTIFICATION OF THE DESYNCHRONIZATION BETWEEN THE CLOCKS OF TWO HBC ACTIVE IMPLANTS - A method for quantification of the desynchronization between the clocks of two medical devices communicating wirelessly, for example, by HBC signals. The devices are separately clocked by slow clocks (CLK
|Adaptive Offset Adjustment Algorithm - An apparatus and method is disclosed to compensate for one or more offsets in a communications signal. A communications receiver may carry out an offset adjustment algorithm to compensate for the one or more offsets. An initial search procedure determines one or more signal metric maps for one or more selected offset adjustment corrections from the one or more offset adjustment corrections. The offset adjustment algorithm determines one or more optimal points for one or more selected offset adjustment correction based upon the one or more signal maps. The adaptive offset algorithm adjusts each of the one or more selected offset adjustment corrections to their respective optimal points and/or each of one or more non-selected offset adjustment corrections to a corresponding one of a plurality of possible offset corrections to provide one or more adjusted offset adjustment corrections. A tracking mode procedure optimizes the one or more adjusted offset adjustment corrections.
|ALL-DIGITAL FREQUENCY SYNTHESIS WITH DCO GAIN CALCULATION - An all-digital frequency synthesizer architecture is built around a digitally controlled oscillator (DCO) that is tuned in response to a digital tuning word (OTW). In exemplary embodiments: (1) a gain characteristic (K
|DATA COMMUNICATION METHOD AND APPARATUS - According to an embodiment there is provided a method of modifying a symbol constellation for use in a data transmission apparatus. The method comprises receiving at a processor a starting symbol constellation suitable for use in a frequency domain parallel modulation system and defined in a complex space. The starting symbol constellation does not necessarily comprise a symbol at a zero point in the complex space. The processor is used to locate or move one of the symbols of the starting symbol constellation at the zero point of the complex space. The newly created symbol constellation may be stored in a storage medium, such as volatile or non-volatile storage, or immediately used for data transmission by mapping bits of data to the symbol constellation and by transmitting the mapped data to a receiver of a frequency domain parallel modulation system.
|METHOD AND APPARATUS FOR CONTROLLING SIGNAL GAIN IN DIGITAL SIGNAL PROCESSING SYSTEM - A method and an apparatus control a signal gain in a digital signal process system are provided. In the method, a peak power of an input signal for each of a plurality of periods is measured. The peak power for each period is compared with a threshold power. A magnitude of a signal of a period where the peak power is greater than the threshold power is controlled.
|OVERPOWER DETECTION DEVICE AND RADIO COMMUNICATION DEVICE - The present invention relates to an overpower detection device
|RECEIVER CIRCUIT AND METHOD PERFORMED BY A RECEIVER CIRCUIT - A method includes a step of correlating a received signal with a pilot sequence to determine a correlation result. The method further includes a step of determining a channel estimate based on a Minimum Mean Square Error scheme that is conditional to an observed parameter, wherein the observed parameter includes the correlation result.
|Method and A Processing Unit for Processing A Data Signal
|TRANSMITTER AND COMMUNICATION APPARATUS - Provided is a transmitter which is small in size and operates with high efficiency and compensates a delay error with high accuracy. A signal generation section
|APPARATUS FOR MEASURING IQ IMBALANCE - The present general inventive concept relates to apparatuses and/or methods for measuring an IQ imbalance. In one embodiment, a signal generator can provide a first IQ signal of a DC component during a first period and the first IQ signal of a first angular frequency during a second period, an IQ up-conversion mixer can up-convert the first IQ signal by a second angular frequency during the first period and up-convert the first IQ signal by a third angular frequency during the second period to output a second IQ signal, an IQ down-conversion mixer can down-convert the second IQ signal by the third angular frequency to output a third IQ signal and an IQ imbalance detector can obtain a first IQ imbalance (e.g., Rx IQ imbalance) from the third IQ signal during the first period and a second IQ imbalance (e.g., Tx/Rx IQ imbalance) during the second period.
|Method and Apparatus for Detecting Communication Channel Delay Asymmetry - The invention provides a method and apparatus for detecting communication channel delay asymmetry between transmission line protection devices. The method comprises: calculating, repeatedly, clock disparity between clocks of the protection devices and communication delays at different paths of the communication channel; comparing the latest calculated clock disparity and communication delays with previously calculated clock disparities and communication delays, respectively; determining a channel switching has happened if a change of the calculated clock disparity exceeds a first threshold, or a change of the calculated communication delays for any path exceeds a second threshold; and determining the channel delays as asymmetrical if a difference between the calculated communication delays of the different paths after the channel switching exceeds a third threshold.
|RE-SAMPLING S-PARAMETERS FOR SERIAL DATA LINK ANALYSIS - A device and method of re-sampling a plurality of S-parameters for serial data link analysis is disclosed. The method includes storing a plurality of S-parameters sets, each S-parameter set being associated with a subsystem and having associated impulse responses and a time interval. An increased time interval is determined based on the time interval associated with each S-parameter set. The impulse responses are zero filled in each S-parameter set to maintain any wrapped ripples and increase the time interval. A plurality of resampled S-parameter sets are generated with a finer frequency resolution to cover the increased time interval.
|DETERMINISTIC SYNCHRONIZATION FOR TRANSMITTING SIGNALS BETWEEN DIFFERENT CLOCK DOMAINS - One embodiment sets forth a technique for deterministic synchronization of signals that are transmitted between different clock domains. The relative phase difference between a source clock domain and a destination clock domain is characterized and the source clock and/or the destination clock are delayed as needed to generate phase-shifted versions of the source and destination clocks for use during a deterministic operating mode. The phase-shifted versions of the source and destination clocks are non-overlapping, meaning that the rising edge of the destination clock does not occur when the source clock is asserted. The non-overlapping source and destination clocks are used by a deterministic synchronization unit to ensure that signals being transmitting from the source clock domain to the destination clock domain are not sampled within a metastability window.
|Detection of Frame Marker Quality - For example, a method of detecting frame marker quality includes: detecting, in a bit-stream sent from a first component to a second component of a common hardware unit, a frame marker having a bit pattern different from an uncorrupted frame marker specified by a communication protocol; and assigning a quality level indicator to the frame marker based on a difference between said bit pattern and a bit pattern of said uncorrupted frame marker.
|SYMBOL MODULATION ACCURACY MEASURING DEVICE, METHOD, PROGRAM, AND RECORDING MEDIUM - An accuracy of a symbol modulation is accurately measured. A symbol modulation accuracy measuring device receives a signal to be measured from a signal output device, which outputs ideal symbol data generated by the ideal symbol data generating unit, and modulated by the symbol modulation unit according to a symbol modulation as the signal to be measured, via a memory, and measures the accuracy of the symbol modulation. The symbol modulation accuracy measuring device includes a symbol demodulation unit that demodulates the signal to be measured according to a symbol demodulation, and a modulation accuracy measuring unit that measures the accuracy of the symbol modulation based on a result of the demodulation by the symbol demodulation unit, and the ideal symbol data recorded in the ideal symbol data generating unit of the signal output device. The symbol modulation accuracy measuring unit acquires the ideal symbol data from the ideal symbol data generating unit via a digital interface or a recording medium.
|METHOD AND APPARATUS FOR REFERENCE SIGNAL PROCESSING IN AN ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING COMMUNICATION SYSTEM - A wireless communication includes a base station that configures a set of non-zero power reference signals corresponding to multiple potential transmission points to one or more users equipment UEs and configures at least one zero-power reference signal, with zero transmission power from one or more of the multiple transmission points. The base station transmits configuration information to at least one UE of the one more UEs, wherein the configuration information corresponds to a set of resource elements that are associated with a set of channel state information reference signals and wherein the set of channel state information reference signals include the set of nonzero-power reference signals and the at least one zero-power reference signal. The UE then performs a channel measurement based on one or more non-zero-power reference signals of the set of non-zero-power reference signals and performs an interference measurement based on the at least one zero-power reference signal.
|Pilot Signal Cancellation Scheme for Mobile Broadband Systems Based on OFDM - Certain aspects of the present disclosure relate to a technique for pilot based inter-carrier interference (ICI) cancellation in time-varying channel environments, such as wireless mobile broadband systems based on Orthogonal Frequency Division Multiplexing (OFDM).
|Method for determining modulation and coding scheme - There is provided a method of determining a Modulation and Coding Scheme (MCS). The method includes predicting an error rate of a symbol and determining a MCS of the symbol using the error rate. Since a MCS level is determined using an estimated error rate and user data is scheduled, multi-user diversity gain can be obtained and the transmission rate can be improved.
|AUTOMATIC GAIN CONTROLLER, TRANSCEIVER AND AUTOMATIC GAIN-CONTROL METHOD THEREOF - An automatic gain-control method for a communication system is comprised of determining a communication distance between the first and second transceivers and controlling gain values of transception stages of the first and second transceivers in correspondence with the communication distance.
|MULTI-ANTENNA WIRELESS COMMUNICATION METHOD, MULTI-ANTENNA WIRELESS COMMUNICATION SYSTEM, AND MULTI-ANTENNA WIRELESS COMMUNICATION DEVICE - Wireless communication devices A and B perform wireless communication with the MIMO technology. The wireless communication devices A and B determine the optimal diversity combining information that optimizes a diversity reception state through a two-way training signal transfer. This determination can be made based on reception level information, baseband reception IQ information, correlation information between a diversity-combining received signal and a predetermined information sequence, or the like, which are obtained when the diversity combining information with respect to each antenna is sequentially changed. The optimal diversity combining information can be determined by receiving training frames or symbols (the number of antennas+1) times.
|SIGNAL DEMODULATION METHOD AND APPARATUS AND SIGNAL MODULATION METHOD AND APPARATUS IN RETURN LINK OF SATELLITE SYSTEM - A technology for modulating and demodulating a burst signal in a return link of a satellite system, in which the burst signal is modulated and transmitted from a transmission end of the return link and a symbol of the burst signal is identified and demodulated at a receiving end. The method includes estimating symbol timing of a burst received through the return link and synchronizing the estimated symbol timing of the burst to reference symbol timing; synchronizing a location of the timing-synchronized burst having the symbol timing synchronized to a location of a reference burst using a preamble symbol and a post-amble symbol of the timing-synchronized burst; and recovering a carrier of the location-synchronized burst whose location has been synchronized to the location of the reference burst using a pilot symbol of the location-synchronized burst.
|Methods and Apparatus for Detecting Errors in Encoding and Decoding of Data - Systems and techniques for improved error detection in data communication. A sending station encodes unencoded data to create an encoded message and passes the encoded data to transmission elements for transmission to a destination receiver. At the same time, error detection is performed using copies of the unencoded data and the encoded message. The encoded message is decoded using a decoding procedure identical to that to be used by the destination receiver. The copy of the unencoded data is compared to the decoded copy of the encoded message, and if the copy of the unencoded data does not match the decoded copy, the presence of an error is identified and error recovery procedures are performed.
|Method and Apparatus for Producing a Desired Data Compression Output - A method and apparatus for testing the functionality of a data decoder is provided. The functionality of a decoder is examined through the used of a functional bitstream. The functional bitstream is a bitstream which when decoded by a properly functioning decoder, produces a desired output. Such a bitstream can be created by receiving an input bitstream, compressing the input bitstream, thereby creating a compressed input bitstream. The compressed input bitstream is then decompressing, thereby creating an intermediate bitstream. The intermediate bitstream is then compressed, thereby creating a compressed intermediate bitstream. The compressed intermediate bitstream is then decompressed, thereby creating an output bitstream. Finally, a comparison is performed to determine if the output bitstream is equivalent to a desired bitstream.
|Underwater data transfer system - The present invention relates to a system that provides underwater data transfer between two remote client systems via an underwater cabled network operable. The cabled network includes at least two data access points each having an access point electromagnetic transceiver; and each remote client system comprising a client electromagnetic transceiver. Each data access point is operable to transfer data between said cabled network and one of said client electromagnetic transceivers via one of inductive magnetic and electromagnetic signals carried through the water.
|FORENSIC DIAGNOSTIC CAPABILITY INCLUDING G.INP - There is a need for a forensic diagnostic capability to facilitate a greater understanding of why xDSL transceivers are subject to otherwise inexplicable service interruptions during Showtime (steady state data transmission mode). In certain exemplary embodiments, diagnostic data from a previous Showtime is stored and then communicated to another transceiver and/or reported (or communicated) to a management entity. The stored diagnostic data can be used to determine why the service interruption occurred. In other embodiments, one or more portions diagnostic data from a last Showtime are stored. In additional embodiments, this diagnostic data is collected immediately prior to exiting Showtime and/or retraining (the "last" data collected prior to exiting Showtime and/or retraining). Alternatively, or in addition, the diagnostic data can be collected during a current Showtime using a sliding window that covers the most recently received signals and communicated to another transceiver and/or a management entity during the current Showtime.
|POSITIONER - The invention relates to a positioner (
|Methods and Apparatus to Combine Data from Multiple Sources to Characterize Communication Systems - A data collector combiner, a network management system, a DSL Optimizer (DSLO), or any combination thereof collects data, parameter(s), characteristic(s), information, or any combination thereof from two or more data sources. The data collector probabilistically combines at least the first and second data to estimate at least one DSL characterizing parameter.
|CIRCUITS, SYSTEMS, AND METHODS FOR MANAGING AUTOMATIC GAIN CONTROL IN QUADRATURE SIGNAL PATHS OF A RECEIVER - A system provides closed-loop gain control in a WCDMA mode and open loop control in an EDGE/GSM mode. Gain control is distributed across analog devices and a digital scaler in a wireless receiver. In the WCDMA mode, a loop filter generates an error signal that is forwarded to analog and digital control paths. The analog control path includes a first adder, a programmable hysteresis element, and a lookup table. The analog control signal is responsive to thresholds, which when used in conjunction with a previous gain value determine a new gain value. The digital control path includes a second adder, a programmable delay element, and a converter. A control word is responsive to a difference of the error signal, a calibration value, and the analog control signal. Blocker detection is provided in the WCDMA mode of operation. A controller sets system parameters using a state machine.
|SYSTEM AND METHOD FOR CLOSED LOOP POWER CONTROL CALIBRATION - A system for calibrating a closed power control loop includes an adder configured to inject a test signal into an adjustable element, a first peak detector configured to determine an amplitude of the injected test signal, a second peak detector configured to determine an amplitude of a return test signal, a comparator configured to determine the difference between the injected test signal and the return test signal, and a calibration engine configured to adjust the adjustable element so that the return test signal is offset from the injected test signal by a predetermined amount.
|Testing Device and Method for a Multiple-Input Multiple-Output Wireless Terminal - An apparatus and method for testing a multi-in multi-out (MIMO) wireless terminal are provided. In the apparatus, a MIMO transmission mode selecting unit includes: a mode selecting module, which is configured to select a MIMO downlink transmission mode currently requiring testing and trigger a corresponding MIMO downlink transmission module during the real-world over-the-air (OTA) test for the MIMO wireless terminal; and the downlink transmission module, which is configured to output downlink test signals which conform to the feature of the selected MIMO downlink transmission mode according to the triggering of the mode selecting module. The method includes: during the OTA test for the MEMO wireless terminal, selecting a MIMO downlink transmission mode currently requiring testing from multiple configured MIMO downlink transmission modes, and outputting downlink test signals that conform to the feature of the selected MIMO downlink transmission mode.
|FREQUENCY DRIFT ESTIMATION FOR LOW COST OUTDOOR UNIT FREQUENCY CONVERSIONS AND SYSTEM DIAGNOSTICS - Systems and devices for controlling frequency drift in satellite broadcast systems. A receiver antenna system for a direct broadcast satellite signal communications system in accordance with one or more embodiments of the present invention comprises an oscillator, a mixer, coupled to the oscillator, for converting satellite signals at a first frequency to signals at an intermediate frequency, an analog-to-digital (A/D) converter, coupled to the mixer, for receiving the signals at the intermediate frequency and for converting the signals at the intermediate frequency at near-real-time to a digital data stream, a Digital Signal Processor (DSP), coupled to the A/D converter, for processing the digital data stream, and a drift estimator, coupled to the DSP, the drift estimator determining a frequency drift of the oscillator, wherein the receiver antenna system corrects the frequency drift of the oscillator using the determined frequency drift.
|Method and Arrangement of Delay Calibration for OFDM System - A method and arrangement in a network entity of delay calibration for an OFDM system in a mobile communication system are disclosed. The delay calibration technique as disclosed includes estimating a time delay difference according to a phase difference between two adjacent sub-carriers, dividing the estimated time delay difference into a coarse time delay and a fine time delay, and compensating the coarse time delay in time domain and the fine time delay in frequency domain respectively.
|MANAGING AVAILABILITY STATUS IN A COMMUNICATIONS NETWORK - A system and a method are disclosed for a presence engine and a method of operating a presence engine for encoding or decoding availability status into a signal representative of an audio signal. The presence engine is configured to manage availability status of a user. The presence engine comprises an input configured to receive a signal representative of an audio signal and an output configured to send a signal representative of an audio signal. The presence engine also comprises a processor configured to encode availability status of a user into a signal representative of an audio signal and/or configured to decode availability status of a user from a signal representative of an audio signal.
|Integrated Transceiver Loop Back Self Test by Amplitude Modulation - This disclosure relates to radio frequency (RF) functional testing of transceivers of wireless devices.
|INPUT MODULE OF PLC - Disclosed is an input module of a programmable logic controller (PLC) capable of counting coefficient values of multiple channels. An input module of a PLC includes a plurality of detection units, a decision unit and a control unit. The plurality of detection units receives a pulse signal corresponding to each channel, applied from a load having a plurality of channels, detects rising and falling edges of the pulse signal, and transmits an output signal that is the detected result. The decision unit receives a plurality of output signals respectively transmitted from the plurality of detection units, detects edges of the plurality of channels, and transmits a detection signal that is the detected result. The control unit identifies the presence of occurrence of an interrupt using the detection signal transmitted from the decision unit and performs a counting process using the applied pulse signal when the interrupt occurs.
|MEASUREMENT OF SYSTEM TIME DELAY - Apparatus and method are presented for measuring the transmitter and antenna system time delay (TAD) of the cadence sync at the input of a conventional 8 VSB data processing system until the emission of the segment sync of the corresponding data frame sync data segment. This includes sequentially conditioning a multi-bit input digital signal containing an initial cadence sync, inserting data patterns into the digital signal, inserting a known data pattern into the data frame at a known position of the data frame and receiving the cadence sync and the known pattern and measuring the time delay therebetween.
|ADJUSTING PHYSICAL LAYER TRANSMISSION PROPERTIES - A transmitting device may determine a physical layer transmission properties based upon an amount of data to transmit via a communications channel. The physical layer transmission properties may comprise a derated tone map that has a lower physical layer transmission throughput capability than an original tone map. An indication regarding the derated tone map may be included in a first message, a portion of a physical layer framing protocol, a physical layer control transmission (such as a frame control symbol), or other transmissions such that the receiving device can derive the derated tone map without significant added overhead.
|RANK ESTIMATION DEVICE, RECEIVER, COMMUNICATION SYSTEM, RANK ESTIMATION METHOD, AND PROGRAM RECORDING MEDIUM - A rank estimation device in which a load on a rank estimation process can be reduced is provided.
|RADIO COMMUNICATION APPARATUS AND RADIO COMMUNICATION METHOD - Provided are a radio communication apparatus and a radio communication method capable of changing an order of interpolation between time domain interpolation and frequency domain interpolation based on a degree of channel variation. According to the present invention, a radio communication apparatus (
|LONG TERM EVOLUTION (LTE) UPLINK CANONICAL CHANNEL ESTIMATION - A method and system for canonical channel estimation in the Long Term Evolution uplink where a multi-frequency signal is generated and then converted to frequency spectrum which is then convolved in the frequency domain with a truncated window function to obtain a time domain channel impulse response. The time domain channel impulse response can be then transformed to a frequency domain to produce a down sampled user channel response, which can be then linearly interpolated to provide a channel estimate for a plurality of subcarriers. Such an approach achieves channel estimation within Long Term Evolution at only canonical locations to reduce complexity without loss in channel entropy.
|SIGNAL TESTING APPARATUS AND METHODS FOR VERIFYING SIGNALS IN SATELLITE SYSTEMS - A signal testing apparatus is provided. The signal testing apparatus generally comprises a recording device that is configured to receive a plurality of signals representative of a plurality of electromagnetic waves that correspond to a pre-defined period of time. The recording device is further configured to record a plurality of digital representations of the signals such that each digital representation corresponds to a separate signal. A processing device is coupled to the recording device, wherein the processing device is configured to introduce at least one operational parameter to each of the digital representations. A play-back assembly is coupled to the recording device and to the processing device, wherein the play-back device is configured to play each of the digital representations simultaneously in real-time to facilitate verification of each of the signals.
|Method and Apparatus for Reference Signal Muting Detection in a Wireless Communication Network - The present invention provides a method and apparatus for autonomously detecting whether a reference signal within an OFDM signal transmitted by a remote transmitter is or is not muted for a given transmission time. Muting or puncturing may be applied to all or only a portion of the reference signal. The method, which may be carried out in an appropriately configured radio apparatus, includes receiving the OFDM signal and calculating a first comparison metric from signal samples of the OFDM signal corresponding to a first set of resource elements of the OFDM signal, and calculating a second comparison metric from signal samples of the OFDM signal corresponding to a second set of resource elements of the OFDM signal. The method continues with determining whether the reference signal is or is not muted for the given transmission time, by comparing the first and second comparison metrics, and foregoing or performing reference signal measurements responsive to determining that the reference signal is or is not muted.
|Periodic Calibration For Communication Channels By Drift Tracking - A method and system that provides for execution of a first calibration sequence, such as upon initialization of a system, to establish an operation value, which utilizes an algorithm intended to be exhaustive, and executing a second calibration sequence from time to time, to measure drift in the parameter, and to update the operation value in response to the measured drift. The second calibration sequence utilizes less resources of the communication channel than does the first calibration sequence. In one embodiment, the first calibration sequence for measurement and convergence on the operation value utilizes long calibration patterns, such as codes that are greater than 30 bytes, or pseudorandom bit sequences having lengths of 2
|Systems, methods, and devices for electronic spectrum management for identifying signal-emitting devices - Systems, methods, and apparatus are provided for device sensing in white space, by identifying sources of signal emission by automatically detecting signals, analyzing signals, comparing signal data to historical and reference data, and creating corresponding unique signal profiles.
|SYNTHETIC INSTRUMENT UNIT - Systems and other embodiments associated with synthetic instrumentation are presented. A reconfigurable synthetic instrumentation unit comprises an input module, with dual input/output ports and conditioning logic to condition an input signal. An RF down converter selectively down converts the conditioned input signal. A sampled RF down converter selectively samples the conditioned input signal. A pair of narrowband A/D converters are configured to convert one of the conditioned signal, the down converted signal and the sampled signal to produce a narrowband digital signal. A pair of broadband A/D converters convert at least one of the conditioned signal, the down converted signal and the sampled signal to produce a broadband digital signal. Signal processing logic selectively performs digital signal processing on the broadband digital signal or the narrow band digital signal.
|SIGNAL TRANSMISSION APPARATUS AND METHOD OF CONTROLLING THE APPARATUS - According to an aspect of the embodiment, According to an aspect of the invention, a signal transmission apparatus transmits a first signal to a transmission line. The apparatus measures a reflection characteristic of the transmission line based on a signal resulting from reflection of the first signal, and measures a transmission characteristic of the transmission line based on a signal resulting from transmission of the first signal through the transmission line. The apparatus determines a transmission clock frequency and a multi-value number based on the reflection characteristic and the transmission characteristic, and modulates information using the transmission clock frequency and the multi-value number to transmit a second signal resulting from the modulation to the transmission line. The apparatus receives the second signal through the transmission line and demodulates the received second signal.
|DATA RECEIVER, DATA COMMUNICATION SYSTEM, AND DATA COMMUNICATION METHOD - A data receiver is disclosed, including an equalization process part, a multi-value oversampling part, and an equalization controller. The equalization process part equalizes serial received data before binarization and outputs the serial received data being equalized. The multi-value oversampling part binarizes the serial received data being equalized by multiple threshold values, conducts oversampling, and generates the multi-value sampling data. The equalization controller detects an eye pattern of the serial received data being equalized based on the multi-value oversampling data, and controls an equalization characteristic of the equalization process part based on a detection result.
|METHOD AND APPARATUS FOR EVALUATING A TIME VARYING SIGNAL - A method for evaluating a received signal varying over an interval includes: (a) obtaining a data sample and a sample time; (b) determining whether the sample exceeds a previous exceeded extremum of the signal; (c) if the sample does not exceed an exceeded extremum, storing the sample; (d) if the sample exceeds the an exceeded extremum, in no particular order: (1) extracting and storing cycle information involving the exceeded extremum; and (2) replacing an earliest exceeded extremum with the sample; (e) outputting first selected data from a storage unit; (f) determining whether the interval has completed; (g) if the interval has not completed, repeating steps (a) through (f); (h) if the interval has completed, checking whether an output buffer is empty; (i) if the buffer is not empty, outputting second selected data from the buffer; 0) if the buffer is empty, terminating the method.
|TESTING A DECISION FEEDBACK EQUALIZER ('DFE') - Testing a Decision Feedback Equalizer ('DFE'), the DFE including a summing amplifier operatively coupled to a plurality of latches and an input signal line for receiving a data signal, including: preventing a differential data signal from being received by the summing amplifier; and iteratively for each tap to be tested: setting a tap coefficient for each tap to zero; setting an output of the plurality of latches to a predetermined value; setting a tap coefficient for the tap to be tested to a full scale value; and determining whether a resultant output signal from the DFE matches a predetermined expected output signal.
|METHOD AND DEVICE FOR THE TIME-SERIAL TRANSMISSION OF RECEPTION SIGNALS OF ELECTROACOUSTIC TRANSDUCERS - A method for the time-serial transmission of received signals of electroacoustic transducers (
|TRANSMITTER AND CONTROL METHOD FOR TRANSMITTING AND CALIBRATING A PHASE SIGNAL AND AN AMPLITUDE SIGNAL - A transmitter for transmitting and calibrating a phase signal and an amplitude signal. The transmitter comprises a phase modulation path, an amplitude modulation path, and a control unit. The phase modulation path transmits the phase signal. The amplitude modulation path transmits the amplitude signal. The control unit delays the signal on at least one of the phase modulation path and the amplitude modulation.
|High Peak to Average Power Ratio (PAPR) Mitigation in High Speed Data Networks Using Symbol Mapping Adjustment - Embodiments provide techniques for high peak to average power ratio (PAPR) event mitigation in high speed data networks, such as cable networks, for example. Embodiments are applicable to multi-carrier and single-carrier modulation systems. Embodiments operate by predicting or detecting the occurrence of a peaking event at the transmitter, and then mitigating potential effects of the peaking event at the transmitter, including application of alternative constellation symbol mappings.
|IMPULSE NOISE MEASUREMENT BY SPECTRAL DETECTION - A method and device are provided for measuring impulse noise in a signal. The method includes: measuring at least one first signal; converting the first signal in the frequency domain; defining a variable-frequency triggering threshold on the basis of stationary characteristics of the first signal; measuring a second signal; converting the second signal in the frequency domain; storing the second signal when the second signal reaches or passes the triggering threshold; and high-pass-filtering the stored signal.
|METHOD AND APPARATUS FOR AN ADAPTIVE FILTER ARCHITECTURE - A system that incorporates teachings of the subject disclosure may include, for example, a method for identifying a spectral region in a radio frequency spectrum, determining a signal strength of the spectral region, determining a correlation factor by correlating the signal strength of the spectral region, identifying from the correlation factor interference in the spectral region, repeating a determination of the correlation factor and an identification of the interference until a desired confidence level has been achieved, and generating coefficient data to substantially suppress the interference in the channel responsive to achieving the desired confidence level. Other embodiments are disclosed.
|CHANNEL FREQUENCY RESPONSE ESTIMATOR FOR A WIRELESS RF CHANNEL - A channel frequency response estimator for estimating the channel frequency response of a wireless RF channel having a time or frequency varying channel frequency response is disclosed. The channel frequency response estimator includes a wireless receiver. An ambiguous channel frequency response estimator is also included and configured to establish multiple channel frequency response estimate candidates for the channel frequency response of the channel. An ambiguity resolver is configured to select a channel frequency response estimate from the multiple channel frequency response estimate candidates that maximizes a goodness of fit of the selected first channel frequency response estimate, and at least two further channel frequency response estimates to a channel model. The channel model models the time or frequency dependent variance of the channel frequency response.
|System And Method To Actively Drive The Common Mode Voltage Of A Receiver Termination Network - An active termination circuit for a differential receiver includes a first receiver element configured to receive a first component of a differential signal, a second receiver element configured to receive a second component of a differential signal, a common mode measurement element configured to receive the differential signal and generate a transmit common mode signal (Vcm) representing an average value of the differential signal, and a receiver (RX) common mode signal node. The termination circuit also comprises an active element configured to receive the transmit common mode signal (Vcm) and provide an output to the receiver common mode signal node, the output configured to drive the value of the signal at the receiver common mode signal node to the value of the transmit common mode signal (Vcm), and a capacitive element coupled to the receiver common mode signal node in parallel with the active element.
|Method and Apparatus for Generating Channel Quality Information for Wireless Communication - A method and apparatus for generating channel quality information, such as may be used for transmit link adaptation, provide different operating modes, such as a first mode that may be used when propagation channel estimates are not reliable, and a second mode that may be used when the propagation channel estimates are reliable. In one or more embodiments, channel quality information is generated using receiver performance information that characterizes receiver performance in terms of a defined channel quality metric, e.g., supported data rates, for different values of receiver input signal quality over a range of propagation channel realizations. Channel quality information can be generated by selecting channel quality metrics according to receiver input signal quality and a desired probability of meeting a defined performance requirement over a range of propagation channel realizations, or by selecting channel quality metrics according to receiver input signal quality and particularized propagation channel realizations.
|SATELLITE RECEIVER PERFORMANCE ENHANCEMENTS - Long time interleaver and listenable audio performance enhancements for a satellite receiver are presented. One enhancement includes comparing a correlation and a predetermined threshold value and blocking satellite signal data transmission from entry into long time interleaver (LTI) device circuitry and forward error correction (FEC) circuitry when the correlation value is the same as, or less than the predetermined threshold value. Another enhancement includes using Reed-Solomon codeword error checking to prevent erroneous baseband signal data from being accepted as good baseband signal data. A further enhancement includes storing symbol timing and frequency data during a strong signal condition of the satellite receiver and using this stored data when the satellite receiver encounters a weak signal condition. Another enhancement includes mitigating DC offset noise in a satellite receiver having a zero-IF tuner.
|CHANNEL SELECTION EXPLOITING MULTIPLE OBSERVATIONS OF THE CHANNEL DELAY SPREAD - A method, a mobile system, and a user device for determining a delay spread are disclosed. A memory
|TRANSMISSION UNIT AND DIAGNOSIS METHOD - A transmission unit connected to a reception unit via a communication cable. The transmission unit includes: a diagnostic data transmitting section to transmit, to the reception unit via the communication cable, diagnostic data converted into signals under a signal conversion condition for a diagnosis, of which a value of at least one parameter is different from a signal conversion condition for a transmission defined as a data-to-signal conversion condition for transmitting data to the reception unit; and a diagnosing section to diagnose a status of the communication cable on the basis of a diagnostic data error rate measured by the reception unit receiving the diagnostic data.
|Signal Classification for Adaptive Signal Detection - Signal received in a wireless network are detected by arranging samples of the signal in a set of windows. For each window, estimating interference, an average signal, noise and interference ratio (SINR), and a channel. For each window, also classifying a type of a process of a set of processes of a receiver. Then, selecting the process for each windows according to the type to detect the signal in the window.
|COMMUNICAITON SYSTEM WITH MODULATION CLASSIFIER AND METHOD OF OPERATION THEREOF - A method of operation of a communication system includes: calculating a shift distance of a received signal having a distortion; calculating an approximate likelihood of the received signal matching a transmitted signal from the shift distance; determining a bias factor from the distortion; and selecting a determined modulation maximizing a combination of the approximate likelihood and the bias factor for communicating with a device.
|Periodic Calibration For Communication Channels By Drift Tracking - A method and system that provides for execution of a first calibration sequence, such as upon initialization of a system, to establish an operation value, which utilizes an algorithm intended to be exhaustive, and executing a second calibration sequence from time to time, to measure drift in the parameter, and to update the operation value in response to the measured drift. The second calibration sequence utilizes less resources of the communication channel than does the first calibration sequence. In one embodiment, the first calibration sequence for measurement and convergence on the operation value utilizes long calibration patterns, such as codes that are greater than 30 bytes, or pseudorandom bit sequences having lengths of 2
|COMMUNICATION CHANNEL CALIBRATION FOR DRIFT CONDITIONS - A method and system provides for execution of calibration cycles from time to time during normal operation of the communication channel. A calibration cycle includes de-coupling the normal data source from the transmitter and supplying a calibration pattern in its place. The calibration pattern is received from the communication link using the receiver on the second component. A calibrated value of a parameter of the communication channel is determined in response to the received calibration pattern. The steps involved in calibration cycles can be reordered to account for utilization patterns of the communication channel. For bidirectional links, calibration cycles are executed which include the step of storing received calibration patterns on the second component, and retransmitting such calibration patterns back to the first component for use in adjusting parameters of the channel at first component.
|Operation of a Transmission Device of a Magnetic Resonance Device - A method for operating a transmission device of a magnetic resonance device is provided. In order to actuate coil elements of a radiofrequency coil with different phases, phase differences in a reference plane are taken into consideration. In a first calibration measurement to be performed once for each transmission path, a first phase of a transmitted radiofrequency signal is measured by an internal measuring device installed permanently in the transmission device spaced apart from the reference plane. A second phase of the transmitted radiofrequency signal is measured by a second, external measuring device to be connected to the reference plane for the first calibration measurement. At least one phase of the first phase and the second phase is taken into consideration in the phase-accurate actuating of the coil elements and/or for correcting further measurements with the internal measuring device.
|ADAPTABLE RECEIVER DETECTION - Methods and apparatuses for adaptable receiver detection are provided. Embodiments include providing, by receiver detection circuitry at a transmitter coupled to a communication link, a voltage to the communication link; determining, by the receiver detection circuitry, a rise time corresponding to a rising edge change of the voltage on the communication link; determining, by the receiver detection circuitry, a fall time corresponding to a falling edge change of the voltage on the communication link; and determining, by the receiver detection circuitry, whether the rise time and the fall time are consistent with the transmitter being coupled through the communication link to a remote receiver.
|TELECOMMUNICATION SIGNALING USING NONLINEAR FUNCTIONS - One exemplary embodiment can describe a method for communicating. The method for communicating can include a step for identifying characteristics of a communications channel, a step for identifying a set of nonlinear functions used to generate waveforms, a step for assigning a unique numeric code to each waveform, a step for transmitting a numeric sequence as a series of waveforms, a step for receiving the series of waveforms, and a step for decoding the series of waveforms.
|PROXIMITY CONTACTLESS COMMUNICATION APPARATUS CAPABLE OF SELECTING APPROPRIATE ENCODING METHOD ACCORDING TO BANDWIDTH BETWEEN ANTENNAS - A comparator circuit compares a test pattern generated by a test pattern generator circuit, with a test pattern transmitted to a memory card and returned from the memory card. A control circuit determines a bandwidth corresponding to frequency components correctly transmitted between a host apparatus and the memory card, based on the returned test pattern, and selects an encoding method requiring a maximum available bandwidth. The control circuit generates a notification message indicating the selected encoding method, and encodes the notification message using the selected encoding method, and transmit the encoded notification message to the memory card. The control circuit establishes communication between the host apparatus and the memory card, when receiving a response message including an acknowledgement to the notification message, from the memory card.
|OPTIMIZATION METHOD OF OPTIMALLY SETTING EMPHASIS AND OPTIMIZATION DEVICE FOR OPTIMALLY SETTING EMPHASIS - In an emphasis optimization device, a calculating unit calculates an inverse characteristic of an amplitude characteristic based on the amplitude characteristic of a transmission path, and an inverse Fourier transform unit performs an inverse Fourier transform on the inverse characteristic to obtain an impulse response. An extracting unit extracts, from the obtained impulse response, an impulse response corresponding to the number of taps necessary for emphasis to be added to a digital signal to be transmitted on the transmission path. An emphasis amount calculating unit converts the extracted impulse response into a value of the emphasis to calculate an emphasis amount.
|METHOD FOR IDENTIFYING AND DETECTING A RADIO SIGNAL FOR A COGNITIVE COMMUNICATION SYSTEM - A method of identifying an RF signal for a cognitive radio system. The signal is identified with a digital watermarking performed downstream from the digital modulation of the symbols to be transmitted. A method of detecting an RF signal watermarked is also disclosed. The identification method includes demodulating the received RF signal as a baseband, converting it digitally, and correlating the digital signal obtained with a predetermined digital signature. The correlation values are averaged using a recursive filter and the maximum value of the average values output from the filter is compared to a threshold to decide whether the RF signal is present.
|DYNAMIC RECEIVER SWITCHING - Dynamic receiver switching is implemented by a receiving device that selects a first receiver having operating characteristics associated with a first optimal operating region to decode one or more first transmissions. The receiving device then selects a second receiver to decode subsequent transmissions. The second receiver has operating characteristics and an optimal operating region that are different from those of the receiver.
|SYSTEMS FOR DETERMINING A REFERENCE SIGNAL AT ANY LOCATION ALONG A TRANSMISSION MEDIA - Systems comprising sensing devices (SD), a signal combiner (SC), signal subtractors (SS), and signal multipliers (SM). SD (
|TRANSMISSION LINE DISCONNECTION DETECTION METHOD AND SLAVE STATION USED FOR THE METHOD - A control/monitor signal transmission system that employs a transmission synchronization scheme in which a master station connected to a single control unit and a plurality of slave stations corresponding to a plurality of controlled apparatuses synchronize with each other through a transmission clock and data is transmitted therebetween over a common data signal line, a transmission line disconnection detection method that enables a disconnection of a transmission line to be detected precisely; and a slave station that is used for this method. A continuous pulse signal that the master station outputs to the common data signal line is provided with a management data region that includes a plurality of pulse signals and that differs from a control/monitor data region including data of a control data signal and data of a monitor data signal.
|Adaptive Partitioning of Traffic Without Additional Probe Traffic - A method is disclosed for adaptively and intelligently partitioning traffic among a plurality of communications channels, without injecting probe traffic into any of the channels. In accordance with the illustrative embodiment, a source node transmits traffic to a receiving node via K communications channels in accordance with partition coefficients α
|SPECTRUM ANALYZER AND SPECTRUM ANALYSIS METHOD - There is provided a spectrum analyzer and a spectrum analysis method capable of promptly performing measurement while preventing the spectrum waveform caused by the fractional spurious components from being displayed.
|Voltage Margin Monitoring for an ADC-Based Serializer/Deserializer in Mission Mode - Various embodiments herein include one or more of systems, methods, software, and/or data structures to determine voltage margin for a high-speed serial data link. Advantageously, the margin determination may be made during normal operation of the data link ("mission mode") such that the performance of the data link is not affected by the voltage margin measurements. That is, the margin measurements may be performed "on line" rather than "off line." To facilitate the voltage margin measurement, a plurality of digital samples from an analog to digital converter (ADC) may be evaluated to determine the most probable bit values (i.e., digital 1's and 0's) that are represented by the digital samples. Then, a method may be used to remove or compensate for ISI effects from one or more of the digital samples, thereby providing an accurate representation of the voltage margin present in a data link. Subsequently, the voltage margin may be periodically monitored over time to detect degradation of the data link.
|PEAK SUPPRESSOR, RADIO COMMUNICATION APPARATUS AND PEAK SUPPRESSION METHOD - There is provided a peak suppressor including a first peak position detector to detect a first time when amplitude of a transmission signal changes in a convex manner and exceeds a specific level as a first peak position, a second peak position detector to detect a second time that is different by a predetermined time from the first peak position when the amplitude of the transmission signal exceeds the specific level as a second peak position, a suppression signal generator to generate a suppression signal for suppressing the amplitude of the transmission signal to a value that is equal to or lower than the specific level, based on amplitude and phase of the transmission signal corresponding to the first and second peak positions detected by the first and second peak position detectors, and an adder to add the suppression signal generated by the suppression signal generator to the transmission signal.
|TRANSMISSION POWER CALIBRATING METHOD AND SYSTEM APPLIED TO WIRELESS APPARATUS - A transmission power calibrating method and a system are provided for a wireless apparatus. The wireless apparatus are controlled by a computer host to be tested at several channels and gains, and a simplified transmission power calibration table is established accordingly. The simplified transmission power calibration table is compared with each of complete transmission power calibration tables in a database. A match is detected between a first complete transmission power calibration table and the simplified transmission power calibration table. When the match is detected, a mapping table is obtained from the first complete transmission power calibration table and stored in a memory of the wireless apparatus. When the match is not detected, the wireless apparatus is controlled by the computer host to establish a second complete transmission power calibration table from which the mapping table is obtained and the mapping table is stored in the memory of the wireless apparatus.
|Doppler Frequency Estimation and Adaptation for MediaFLO Systems - A technique for Doppler frequency estimation and adaptation in a MediaFLO™ (Forward Link Only) receiver system includes receiving Orthogonal Frequency Division Multiplexing (OFDM) symbols in the receiver, dividing a Doppler frequency range into N ranges corresponding to N interpolation filters; determining a correlation between two OFDM symbols separated by time; estimating a Doppler frequency by the correlation of OFDM symbols; determining a ratio of the correlation of OFDM symbols; comparing the determined ratio of the correlation of OFDM symbols with a look up table of α stored at a receiver to determine a corresponding Doppler frequency; mapping α ranges stored at the look up table to suitable interpolation filters; estimating an interpolation filter from the mapped α ranges mapped against determined α ratio; adapting Time Domain Interpolation (TDI) to the selected interpolation filter; and synchronizing receiver to the TDI filter.
|SIGNAL RECEIVING METHOD AND RECEIVER - A demodulation unit demodulates a received signal in which carrier wave of a navigation message that is modulated according to a BPSK modulation scheme are included. An error detection processing unit performs an error detection process on the demodulation result using an error detection bit that is included in the demodulation result. A verification word generator generates a verification word using the demodulation result and a check code when an error is detected by the error detection process, the check code being determined in advance for each bit of the navigation message based on a predetermined encoding rule. An estimation unit estimates an originating bit of a demodulation error by comparing the verification word generated by the verification word generator with a verification word table stored in a storage unit. A correction unit corrects the demodulation result by inverting the bit values of bits subsequent to the estimated originating bit.
|HIGH RESOLUTION SYMBOL TIMING TRACKING - Embodiments of the present disclosure prove an apparatus and method for symbol timing tracking. Such embodiments are configured to obtain a sampling time for sampling a signal pulse; generate a symbol value for the sampling time from actual sample values of the signal pulse corresponding to predetermined sampling times by interpolating the symbol value utilizing the predetermined sampling times and the actual sample values, wherein the sampling time is not included as one of the predetermined sampling times; and utilize the symbol value to determine an optimal sampling time for sampling the signal pulse.
|METHODS AND DEVICES FOR DETECTING ELECTROMAGNETIC INTERFERENCE ON DATA TRANSMISSION LINES - A method for remotely detecting electromagnetic interference on a data transmission line of a communication network includes measuring at a client site a noise power spectrum on the data transmission line as a function of frequency, for a frequency range. The noise is present when the data transmission line is not carrying a data signal. The method further includes forwarding the measured noise power spectrum to a remote computer at a network operator's site, determining periodicities in the measured power spectrum by the remote computer, and determining the switching frequency of a power supply unit at the client site by the remote computer based on periodicities in the power spectrum.
|METHOD WHICH PERMITS A BLOCK-BASED FILE TO BE PLAYED OUT DURING TRANSMISSION - A file (FI) is transmitted via a first channel (CH
|MULTIPLE-CHANNEL TRANSMISSION OVER A SINGLE-WIRE BUS - A method for transmitting at least a synchronization and a data signal on a single-wire bus between a master device and at least one slave device, wherein a first transmission channel from the master device to the slave device modulates the periodic pulse width between a first level and second level of a same sign voltage relative to a reference potential, and a second transmission channel amplitude modulates at least one of the voltage levels between the level and at least one third level different from the two others and from the reference potential.
|DEVICE AND METHOD OF ESTIMATING SYMBOL USING SECOND ORDER DIFFERENTIAL PHASE VECTOR - Provided is a method of estimating a symbol. The method may include deriving phase components of input data, applying a second order differentiation to the phase components to obtain a second order differential phase vector, and estimating symbols corresponding to the input data using the second order differential phase vector.
|Communication Via A Multimode Constellation - An apparatus includes a digital data transmitter capable of sequentially exciting different sets of one or more propagation modes in a physical communication channel. Each set of one or more propagation modes has a different spatial distribution of transmitted energy in the channel. The digital data transmitter is configured to sequentially change the excited set of one or more propagation modes to transmit a different value of data to the communication channel.
|Decision Boundary Estimation for MIMO Wireless Receivers - In a wireless receiver, an estimated decision boundary for use in detecting symbol values from one group of combined received symbols is calculated based on a estimated traffic-to-pilot channel scaling ratio or an estimated decision boundary corresponding to another group of combined received symbols. By properly combining the information derived from the latter group of combined received symbols with channel estimation information for the former group, a decision boundary estimate for the former group can be obtained without the use of amplitude or power information for the latter group of symbols.
|TRANSMISSION CHARACTERISTIC ADJUSTMENT DEVICE, TRANSMISSION DEVICE AND METHOD FOR ADJUSTING TRANSMISSION CHARACTERISTIC - A transmission characteristic adjustment device includes: a setting process portion that sets a setting value concerning each transmission characteristic of a plurality of electric signals to at least one of a sending device that sends the plurality of electric signals and a receiving device that receives the plurality of electric signals; a generation process portion that acquires each error rate calculated based on identification information included in each of the plurality of electric signals whenever the setting value is changed, and generates a table on which a plurality of sets of the setting value and the error rate are recorded; and an adjustment process portion that adjusts the setting value based on the table.
|Determining Spectral Samples of a Finite Length Sequence at Non-Uniformly Spaced Frequencies - Techniques disclosed herein are generally related to methods and devices for determining spectral samples for a finite length sequence. Some example methods include, for each time-indexed sample in a data sample sequence comprising a plurality of samples, generating a sample-specific phase value set associated with a respective time index of the sample and a set of predetermined frequencies. Some examples further include, mapping each sample-specific phase value set to a corresponding sample-specific iso-phasor set and calculating an altered iso-phasor set. Some examples include generating a rotated sample value set by unmapping the altered iso-phasor set to obtain real and imaginary components of the sample rotated by the corresponding sample-specific phase value set. Some addition examples include summing selected rotated sample values from each of the sets of rotated sample values to create a spectral sample vector having a spectral sample of the sequence and outputting the spectral sample vector.
|Precoding Method and Apparatus in Multiple Input Multiple Output System - Embodiments of the present invention disclose a precoding method and apparatus in a multiple input multiple output system. The method includes receiving a non-constant modulus channel information matrix fed back by a UE; processing the non-constant modulus channel information matrix and removing amplitude information, and obtaining a precoding matrix according to a constant modulus channel information matrix; and precoding data to be sent by using the precoding matrix.
|Dsl System Estimation - Estimates of a communication system configuration, such as a DSL system, are based on operational data collected from a network element management system, protocol and users. The operational data collected from the system can include performance-characterizing operational data that typically is available in the OSL system via element-management-system protocols. Generated estimates and/or approximations can be used in evaluating system performance and directly or indirectly dictating/requiring changes or recommending improvements in operation by transmitters and/or other parts of the indication system. Data and/or other information may be collected using internal means or using system elements and components via e-mail and/or other extra means. The likelihood of the models accuracy can be based on various data, information and/or indicators of system performance, such as observed normal operational data, test data and/or prompted operational data that shows operating performance based on stimulation signals.
|MULTI-VALUED DRIVER CIRCUIT - A multi-valued driver circuit selectively outputs, to a transmission line, one from among multiple voltages according to a selection signal. A memory circuit stores setting data which define the respective levels of the multiple voltages. According to the selection signal, a selector circuit selects one from among the multiple setting data stored in the memory circuit. A Thevenin termination circuit outputs a voltage that corresponds to the upper M bits of the data thus selected by the selector circuit. An R-2R ladder circuit outputs a voltage that corresponds to the lower Nl bits of the data thus selected by the selector circuit.
|WAKE-UP CONTROL SYSTEM AND METHOD FOR CONTROLLING RECEIVER WAKE-UP - A wake-up control system comprises a plurality of different signal analyzer units. The plurality of different signal analyzer units may process a value of a different parameter of an incoming signal received at an input of a receiver and provide a false wake-up indication for the parameter when the value of the parameter is outside an acceptance range for the value. The system further comprises an evaluation unit connected to the plurality of different signal analyzer units for receiving the false wake-up indications. The evaluation unit may provide a false wake-up parameter information identifying an identified parameter of the different parameters when a sum of the false wake-up indications is outside an occurrence range for the false wake-up indications for the identified parameter.
|ITERATIVE ESTIMATOR AND METHOD OF CHANNEL AND NOISE VARIANCE FOR MULTIPLE INPUT MULTIPLE OUTPUT ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING SYSTEM - A reception apparatus including: a detection unit detecting extrinsic information based on an output of a tentative symbol decision unit, an output of a channel estimation unit, and an output of a noise variance estimation unit that are obtained from a previous iteration process; a Cyclic Redundancy Check (CRC) aided channel decoding unit outputting an encoded and interleaved bit, or a posteriori information thereof based on the extrinsic information; the tentative symbol decision unit determining a tentative transmission symbol based on an output of the CRC aided channel decoding unit; the channel estimation unit estimating a channel based on an output of the tentative symbol decision unit or a pilot symbol; and the noise variance estimation unit estimating a noise variance or an initial noise variance based on the output of the tentative symbol decision unit and the output of the channel estimation unit is provided.
|RESOURCE ADAPTIVE SPECTRUM ESTIMATION OF STREAMING DATA - Streaming environments typically dictate incomplete or approximate algorithm execution, in order to cope with sudden surges in the data rate. Such limitations are even more accentuated in mobile environments (such as sensor networks) where computational and memory resources are typically limited. Introduced herein is a novel "resource adaptive" algorithm for spectrum and periodicity estimation on a continuous stream of data. The formulation is based on the derivation of a closed-form incremental computation of the spectrum, augmented by an intelligent load-shedding scheme that can adapt to available CPU resources. Experimentation indicates that the proposed technique can be a viable and resource efficient solution for real-time spectrum estimation.
|Method and Device for Determining a Quality of a Clock Signal - Method, device and system for detecting a disturbance, e.g., at least one short mechanical impact (shock or vibration) on a clock of a slave device by detecting a non-typical variation of a tracking error, i.e., a tracking error having a deviation that exceeds a predetermined threshold, wherein such a non-typical variation can be determined by the deviation from a statistical measure, e.g., a variance or a standard deviation, such that the determination of the quality of a clock signal is advantageously allowed and thus suitable counter-measures are provided. The method, device and system are applicable for all kinds of technical systems comprising slave devices that have a clock, e.g., devices in industrial and automation systems. The method, device and system are also applicable in communication systems that use a protocol to synchronize the clocks of its devices, e.g., Profinet.
|CROSSTALK CONTROL METHODS AND APPARATUS UTILIZING COMPRESSED REPRESENTATION OF COMPENSATION COEFFICIENTS - An access node of a communication system is configured to control crosstalk between channels of the system. Vectoring circuitry in the access node is configured to determine estimates of crosstalk from one channel of the system into another channel of the system on multiple sub-channels, to determine compensation coefficients for respective ones of the multiple sub-channels based on the crosstalk estimates, and to generate compensated signals for respective ones of the multiple sub-channels based on the compensation coefficients. At least a given one of the compensation coefficients is determined for use in the generation of compensated signals by decompressing a compressed representation of the given compensation coefficient. The compressed representation is decompressed by evaluating a parameterized function of a plurality of control parameters at least one of which does not correspond to any of the compensation coefficients. The compensated signals may be pre-compensated signals or post-compensated signals.
|COMMUNICATION ADDRESS DETECTION APPARATUS, CONNECTOR WITH BUILT-IN CONTROL CIRCUIT, AND COMMUNICATION ADDRESS DETECTION METHOD - There is provided a communication address detection apparatus, a connector with a built-in control circuit, and a communication address detection method capable of preventing abnormal operations even in cases when a voltage level to be input to any one of a plurality of communication address setting terminals has inverted due to some faults. In a communication address detection apparatus for detecting a communication address in accordance with a combination of voltage levels of high or low levels input to a plurality of communication address setting terminals, the combination of the voltage levels with the assigned communication address is set which is stored in a communication address information storing unit (
|METHOD FOR IDENTIFYING RECEIVED SYMBOLS CORRUPTED BY BURST NOISE AND RELATED DEVICE - A method for identifying a corrupted received signal at a receiver is described. A received signal may include symbols. Each symbol may have a value of a Galois field associated therewith. The receiver may be configured to store a logarithm of normalized probability mass functions and corresponding Galois field values for each of the plurality of symbols. The normalized probability mass functions may be normalized with respect to a greatest probability mass function of a given symbol of the plurality of symbols. The method may include comparing, for each of the plurality of symbols, a logarithm of normalized probability of an n-th best probability value with a respective threshold, counting a number of the logarithms that exceed the respective threshold and generating, for each of the plurality of symbols, a score corresponding to the number. The method may also include calculating a moving average of the scores, and comparing the calculated moving average with an output threshold and flagging a just received one of the plurality of symbols as corrupted based upon the comparison.
|RECEIVER CIRCUIT - A receiver circuit includes: a first sampling circuit to sample input data in synchronization with a first edge of a sampling clock signal; a second sampling circuit to sample the input data in synchronization with a second edge of the sampling clock signal; a duty-cycle-distortion detection circuit to detect a duty-cycle-distortion amount indicating an error in a duty ratio of the sampling clock signal based on first data which is sampled by the first sampling circuit and second data which is sampled by the second sampling circuit; a correction circuit to correct the first data or the second data to generate first corrected data or second corrected data, respectively, based on the duty-cycle-distortion amount; and a clock data recovery circuit to select data out of the first corrected data and the second data and to recover the selected data.
|Methods and Devices for Transmission Line Analysis - Improved diagnostics of transmission line (
|CALIBRATION OF SMART ANTENNA SYSTEMS - The present invention relates to a method, system, apparatus, and computer pro-gram product for transmitting or receiving a plurality of time-duplexed transmission signal components via respective transmission or reception chains and respective antenna elements of a smart antenna system. A calibration signal is temporarily coupled into or from the transmission or reception chains via a selected one of the transmission or reception chains by using a portion of the transmission signal components, and a calibration signal parameter, influenced by said transmission or reception chains, is measured relative to a selected one of the transmission or reception chains. Then, a beamforming process of said smart antenna system is calibrated in response to a result of the measuring.
|TEST DEVICE AND METHOD OF DETECTING AN IMBALANCE IN A POWER LEVEL OF A DIGITAL CHANNEL - The present invention provides a test device and a method enabling automatic detection of an imbalance in a power level of a digital channel. The test device includes an attenuator, a tuner, a demodulator, and an evaluation unit. According to the method, a plurality of channels are attenuated at a plurality of attenuation levels, by means of the attenuator. A digital channel is selected from the plurality of channels, by means of the tuner. A modulation error ratio (MER) of the digital channel is measured at the plurality of attenuation levels, by means of the demodulator. A variation of the MER of the digital channel with attenuation level is then evaluated, by means of the evaluation unit, to detect an imbalance in a power level of the digital channel.
|Channel Estimator and Channel Estimation Method - A channel estimator and a channel estimation method are provided. The channel estimator comprises a storage module, for storing a plurality of channel responses of first pilot signals over a plurality of continuous pilot sub-channels, and a plurality of channel responses of second pilot signals over a scatter pilot sub-channel; and a calculation module, for calculating a channel response at a time point without a pilot signal over the scatter pilot sub-channel according to the channel responses of the first pilot signals and the channel responses of the second pilot signals.
|APPARATUS AND METHOD OF CONTROLLING DRIVING CURRENT OF TRANSMISSION - A method of tuning a driving current of a data transmission interface includes: utilizing a driving current with a present current value to continuously send a test data to a receiving end; accumulating a number of times that the test data is sent to generate a transmission counting result; determining whether a transmission error occurs while the test data is sent to the receiving end and accumulating a number of times that the transmission error occurs to generate a transmission error counting result; and when the transmission counting result reaches a predetermined value, determining how to tune the present current value of the driving current according to the transmission error counting result.
|METHOD OF TAGGING SIGNALS USED FOR LEAKAGE DETECTION AND/OR MEASUREMENT IN xDSL DATA TRANSMISSION NETWORKS AND APPARATUS FOR DETECTION AND/OR MEASUREMENT OF LEAKAGE SOURCES IN xDSL DATA TRANSMISSION NETWORKS - A method of tagging signals for leakage detection and measurement in xDSL data transmission networks which uses additional signals carrying the tagging information and transmitted in these networks. A narrowband tagging signal or signals are placed in unused parts of an xDSL signal frequency spectrum or in its proximity.
|APPARATUS FOR DYNAMICALLY ADJUSTING VIDEO DECODING COMPLEXITY, AND ASSOCIATED METHOD - An apparatus for dynamically adjusting video decoding complexity includes a decoding resolution control circuit and an adaptive spatial resolution decoder. The decoding resolution control circuit is arranged to dynamically determine whether at least one portion of a plurality of frames should be decoded in accordance with a specific resolution differing from an original resolution of the plurality of frames. In addition, the adaptive spatial resolution decoder is arranged to decode the plurality of frames according to whether the at least one portion of the plurality of frames should be decoded in accordance with the specific resolution. In particular, the apparatus further includes a system capability analyzing circuit arranged to analyze system capability of at least a portion of the apparatus, in order to generate analyzing results for being sent to the decoding resolution control circuit. An associated method is also provided.
|APPARATUS, AND ASSOCIATED METHOD, FOR COMMUNICATING A DATA BLOCK IN A MULTI CARRIER MODULATION COMMUNICATION SCHEME - Apparatus, and an associated method, for sending a data block in an OFDM, or other MCM, communication system with reduced PAPR is provided. The data block is combined with a random scrambling sequence. An IDFT operation is performed upon the combined sequence, and its PAPR, peak-to-average power ratio, is calculated. The PAPR is compared against a threshold. If the PAPR is smaller than a threshold, the transformed, combination sequence is transmitted. Otherwise, a different scrambling sequence, if available, is used to form a new combination sequence, and the process iterates until either a PAPR smaller than the threshold is obtained, or a pre-defined maximum number of iterations is reached. If the maximum number of iterations is reached and no combination sequence is created that leads to an acceptable PAPR, then the transformed, combination sequence that exhibits the smallest PAPR level is selected for transmission.
|POWER SPECTRAL DISTRIBUTION MEASUREMENT TO FACILITATE SYSTEM ACQUISITION - Wireless devices and techniques providing improved system acquisition in an environment of multiple co-existing technologies over a common frequency band are disclosed. In one aspect, at a remote terminal, a power spectral distribution (PSD) of received signals is sequentially measured in contiguous segments of a frequency band of interest. One or more characteristics of the measured PSD is compared to at least one predetermined metric to identify the presence or absence of at least one technology type of the received signals in frequency locations across the band. A system acquisition operation is performed in accordance with the identification, such as a tailored scan of channels at locations where a desired technology is identified.
|METHOD AND APPARATUS FOR PERFORMING MULTI-ANTENNA TRANSMISSION - A method and apparatus for performing beamforming are provided herein. During operation, a mobile device will notify a base station of the situation in which one or more of its antennas has become unusable. Using this technique, the Multiple Input, Multiple Output (MIMO) algorithms employed at the base station will be adjusted accordingly.
|METHOD FOR DETERMINING AUDIO BROADCAST TRANSMISSION SIGNAL COVERAGE - Computer implemented methods and systems for the prediction of the reception of a desired in-band on-channel digital audio broadcast signal (IBOC DAB) are described. A method includes computing a first ratio of a weaker undesired adjacent broadcast signal to a stronger undesired adjacent broadcast signal; computing a second ratio of the desired IBOC DAB signal to the stronger undesired adjacent roadcast signal. The method also includes computing a minimum allowable reception ratio based on the second ratio and the slope and intercept of a line, wherein the slope and intercept of the line is based on both (i) a plurality of ratios of a weaker adjacent broadcast signal to a stronger adjacent broadcast signal and (ii) a plurality of ratios of a desired IBOC DAB signal to a stronger adjacent broadcast signal. Reception is predicted when the computed minimum allowable reception ratio is less than the first ratio.
|SYSTEMS AND METHODS FOR BEAMFORMING MEASUREMENTS - Systems and methods are disclosed herein to provide communication test systems for the testing of multiple-input multiple-output (MIMO) radio frequency wireless data communication devices, systems and networks, including Multi-User MIMO (MU-MIMO) devices and systems. In accordance with one or more embodiments, a test system containing an integrated MIMO signal analyzer is disclosed that includes a protocol engine operative in conjunction with a waveform generator and waveform analyzer that analyzes the signal waveform of a device under test. Such a test system may offer improved capabilities such as a simpler and more flexible measurement of complex MIMO signal waveforms, more automated measurements of MIMO waveforms including beamforming functions, and more accurate measurement of the efficiency of MIMO related functions such as channel estimation, transmit precoding and beamforming.
|TRANSMITTING METHOD AND TRANSMISSION SYSTEM USING THE SAME - A transmitting method and transmission system using the same is applied to selectively use a space block-coding module to transmit a transmitted data. Each data stream of the transmission data is transmitted using the transmitting paths, and the transmission qualities of the transmitting paths are detected to decide whether the space-block encoding module works or not.
|Powerline Control Interface in Photovoltaic Environment for Frequency and Amplitude Modulation Transmitter - An apparatus is disclosed where a Maximum power point tracking (MPPT) circuit is used to transmit data into the photovoltaic network, where the PLC communication is pulling the required transmit energy from the photovoltaic network, where the transmit chain is using the MPPT transistor of the photovoltaic DC Optimizer, where the transmit chain is transmitting data using Standard modulation such as ASK, FSK, S-FSK, BPSK, OFDM, etc. . . . where the transmitted data are passed on to the powerline network by the use of an "Input signal" adaptation stage, where signals summation is performed to create a command signal used to control the transmission of data by providing enough voltage to polarize the Transistor (i.e: MOS FET) used in the powerline path.
|Controlling a Transmit Path Based on Monitored Error Vector Magnitude (EVM) Performance - Embodiments provide systems and methods to dynamically control a radio frequency (RF) transmitter based on monitored error vector magnitude (EVM) performance. Embodiments are enabled by a feedback path that allows estimating the EVM at the output of the transmitter and controlling the transmitter, including the power amplifier (PA), accordingly. As such, the transmitter (and the PA) can be operated as close as possible to the ideal operating point that meets, based on actual conditions, a specified EVM performance and desired output power. By doing so, the overall power consumption of the transmitter is reduced.
|Method for reliable injection of deterministic jitter for high speed transceiver simulation - A method and a corresponding system for characterizing the performance of a clock and data recovery circuit in a digital transceiver is presented. The method comprises phase modulating a jitter-free data signal by a testing signal having added data jitter and measuring the time the clock and data recovery system takes to achieve bit lock of a phase modulated signal. Data uncorrelated timing jitter corresponding to a user defined probability distribution is included in the jitter testing signal. Utilization of a variable probability distribution in generating data uncorrelated timing jitter, as provided by the present invention, allows for greater flexibility and accuracy in clock and data recovery circuit testing and characterization.
|METHODS AND APPARATUS FOR LOW POWER AUDIO VISUAL INTERFACE CALIBRATION - Methods and apparatus for calibration of interface operation of a display device. In one exemplary embodiment of the invention, an embedded DisplayPort (eDP) source element (such as a graphics processing unit (GPU)) configures itself to support the minimum requirements necessary to support a sink element (such as a screen display). Unlike prior art solutions, minimum sink requirements are identified during a calibration process, and the source is configured accordingly. By tailoring the source to the specific requirements of the sink, the device can initialize faster, consume less power, etc. Moreover, in another aspect of the present invention, if a device does not initialize to an expected configuration based on prior calibration settings, the device can be flagged as having faulty or failing components.
|Multiple Input Multiple Output Antenna Module and Associated Method - A multiple input multiple output (MIMO) antenna module, comprising a first signal feed port coupled to a first antenna element disposed along a first edge of a PCB, a second signal feed port coupled to a second antenna element disposed on the PCB and a transceiver operable to be selectively coupled to either or both of the first and second signal feed ports. The first and second antenna elements form a plurality of antenna elements confined to a peripheral section surrounding a central region of the PCB of the MIMO antenna module.
|Method and System for Compensating a Delay Mismatch Between a First Measurement Channel and a Second Measurement Channel - A method and a system for compensating a delay mismatch between a first measurement channel and a second measurement channel is disclosed. A method for compensating a delay mismatch between a first measurement channel and a second measurement channel includes providing a reference point for starting the first and second measurement channel, and starting the first measurement channel after expiration of a first delay period which begins at the reference point. The method further includes starting the second measurement channel after expiry of a second delay period which begins at the reference point, wherein a difference between a length of the first delay period and a length of the second delay period is substantially equal to the delay mismatch between the first measurement channel and the second measurement channel.
|SIGNAL TRANSITION DETECTION CIRCUIT AND METHOD OF THE SAME - A signal transition detection circuit is provided. The signal transition detection circuit comprises a counter module, a DAC, a comparator and a digital sampling module. The counter module generates a digital step signal. The DAC converts the digital step signal into an analog input signal and transmits it to an under-test circuit such that the under-test circuit generates an output signal transiting from a first stable level to a second stable level, wherein a transition section is located between the first and the second stable level. The comparator receives and compares the output signal with a default value to generate a normalized output signal. The digital sampling module samples the normalized output signal to retrieve impulses such that when the number of the impulses is accumulated to be larger than a reference value, a corresponding step of the digital step signal is determined to be a transition point.
|Time-Stamped Emissions Data Collection for Process Control Devices - The claimed method and system provide a process control device monitoring system and a process control valve assembly with a process control device monitoring system to measure one or more operating states of a process control device. The process control device monitoring system may also associate a time-stamp with the one or more measured operating states of the process control device in response to a trigger generated based on the one or more measured operating states. The process control device monitoring system may also transmit the time-stamp and an indication of the one or more operating states to a monitoring device.
|MEASURING THE I/Q IMPAIRMENTS OF A RECEIVER - Systems and methods for measuring transmitter and/or receiver I/Q impairments are disclosed, including iterative methods for measuring transmitter I/Q impairments using shared local oscillators, iterative methods for measuring transmitter I/Q impairments using intentionally-offset local oscillators, and methods for measuring receiver I/Q impairments. Also disclosed are methods for computing I/Q impairments from a sampled complex signal, methods for computing DC properties of a signal path between the transmitter and receiver, and methods for transforming I/Q impairments through a linear system.
|METHOD FOR CONTROLLING RECEIVING DIVERSITY OF A RECEIVER AND A MOBILE STATION - A method for controlling receiving diversity of a receiver and a mobile station are provided. The method comprises determining single antenna receiving quality indicators for all activated antennas if a receiver receiving quality indicator of the receiver is above a first threshold, and deactivating all the activated antennas except one activated antenna with a single antenna receiving quality indicator indicating best receiving quality based on the determined single antenna receiving quality indicators.
|Method and Arrangement in a Wireless Communication System - The invention relates to methods and arrangements for rank adaptation for transmissions over a multipie-input-muttipie-output, M1MO, channel in a wireless communications system. A receiving node (
|METHODS AND APPARATUS FOR ERROR RATE ESTIMATION - Methods and apparatus for estimating received error rates. In one embodiment, the estimation of received error rates is conducted in relation to a bus interface such as a high-speed High-Definition Multimedia Interface (HDMI) interface, and the method utilizes corrupted symbols that violate TMDS symbol rules, the corrupted symbols being easily detected and counted. In one exemplary implementation, a symbol error rate (SER) can be estimated from the number of detected invalid symbols. The SER can be used to diagnose the performance of the HDMI interface, and optionally as a basis for selecting or implementing corrective action(s).
|Synchronous Mode Tracking of Multipath Signals - In one embodiment, a method comprising sampling by a first sampling unit a first signal received via a first antenna; and sampling by a second sampling unit a second signal received via a second antenna, the sampling of the second signal commencing in synchronization with the sampling of the first signal by the first sampling unit based on an accumulated value, the first and second signal sharing common information.
|TESTING A DECISION FEEDBACK EQUALIZER ('DFE') - Testing a Decision Feedback Equalizer ('DFE'), the DFE including a summing amplifier operatively coupled to a plurality of latches and an input signal line for receiving a data signal, including: preventing a differential data signal from being received by the summing amplifier; and iteratively for each tap to be tested: setting a tap coefficient for each tap to zero; setting an output of the plurality of latches to a predetermined value; setting a tap coefficient for the tap to be tested to a full scale value; and determining whether a resultant output signal from the DFE matches a predetermined expected output signal.
|SELF SYNCHRONIZING DATA COMMUNICATION METHOD AND DEVICE - A method of receiving a data transmission includes detecting a first switching of a transmission signal to a first signal value, starting a duration measurement of a first time interval that begins with detecting the first switching of the transmission signal, detecting a second switching of the transmission signal to a second signal value, stopping the measurement of the first time interval duration and starting a second duration measurement of a second time interval, detecting a third switching of the transmission signal to the first signal value or to a third signal value, stopping the second measurement in response to detecting the third switching, determining a relation of the first and second time interval durations from the first and second measurements, and determining a data value of the transmission signal based on the determined relation.
|Protection of Communication Systems Against Repetitive Electrical Impulse Noise - A method limits the effect of repetitive electrical impulse noise in a communication system. The presence of the repetitive electrical impulse noise is detected during communication service. If the repetitive electrical impulse noise is detected, then a message is transmitted which signals that the repetitive electrical impulse noise is present. Other systems and methods are disclosed.
|Narrowband Diagnostics for Twisted Pair Wiring - A test system for diagnosing twisted pair wiring includes a system processor in communication with a subscriber line interface module, which includes a codec and a SLIC (Subscriber Line Interface Circuit). The SLIC transmits a waveform having a frequency used for voice or baseband modem transmissions onto the twisted pair wiring. The system processor transmits a digital PCM (Pulse Code Modulation) stream to the codec, and the codec converts the digital PCM stream into the waveform transmitted onto the twisted pair wiring. In response to the transmitted waveform, the SLIC senses current on the twisted pair wiring. The codec generates an output waveform corresponding to the sensed current. The system processor receives the output waveform from the codec as a digital PCM stream, synchronizes the transmitted waveform and the output waveform at a single sample, and determines electrical properties of the twisted pair wiring from the output waveform.
|COMMUNICATION SYSTEM, APPARATUS AND METHODS FOR CALIBRATING AN ANTENNA ARRAY - A method for calibrating (
|Detecting the Modulation Type and/or Constellation Order of a PSK/QAM-Modulated Signal - A system and method for determining the modulation type and constellation order of an input signal given that the modulation type and constellation order are known to belong to set of possible types/orders. A computer operates on samples of the input signal to compute signal features. The computer classifies the modulation type and the constellation order by comparing each feature to one or more corresponding threshold values. The results of the comparisons are used to determine the modulation type and constellation order of the input signal from the set of possible types/orders. The classification may be performed based on a decision tree, each leaf node of the decision tree corresponding to a type/order combination, and each non-leaf node corresponding to one or more of the comparisons. The set of possible types/order may include PSK with a number of different constellation orders and QAM with a number of different constellation orders.
|Identifying Rogue GSM Base Stations by Intercepting Downlink Beacon Channels - System and methods and memory media for identifying a rogue base station. A receiver captures an input signal that includes a mixture of the rogue station's transmission and the transmission of a victim base station. The victim station's transmission is removed from the mixture. A plurality of channel signals are extracted from the residual signal. The channel signals are analyzed which of them are "valid", i.e., contain a GMSK-modulated GSM signal. The "valid" channel signals are low pass filtered and then analyzed to determine which of them corresponds to the beacon channel. Information identifying the rogue base station is extracted from the beacon channel.
|CALIBRATION SYSTEM AND METHOD - Receiving a modulated carrier signal that is modulated using a reference signal, wherein an acquisition by a digitizer is synced to the reference signal such that the modulated carrier signal has known timing with respect to a start of an acquisition within the digitizer. Further including routing the modulated carrier signal through a receiver system to generate a processed signal, receiving the processed signal at the digitizer, digitizing the processed signal at the digitizer, and determining a delay of the modulated carrier signal routed through the receiver system based on the timing of the processed signal.
|Method of Using Average Phase Difference to Measure a Distance and Apparatus for the Same - Apparatus for positioning and method for the same are disclosed. The apparatus comprises two transceivers and four time-to-digital converters. The time-to-digital converters compare the phase difference between two signals, one is the crystal oscillation and the other is the phase of the IF (intermediate frequency) signal extracted before ADC receiving by the transceiver. The method comprises the following steps: The first place transmits a first wireless signal by a first transceiver to the second place. The second place then responds a second wireless signal by a second transceiver to the first place. The first phase difference at the first place is then measured by the time-to-digital converter. The second phase difference at the second place is also measured. The distance between the first place and the second place is proportional to one half of the sum of first phase difference and the second phase difference.
|Rejection of Interferers - A filter for filtering a received signal to attenuate an interferer therein, the interferer having a component at an interferer frequency, and the filter comprising: an intermediate filter providing a passband and a stopband; a first frequency converter configured to form a first intermediate signal by frequency-shifting an input signal derived from the received signal such that a component of the input signal at the interferer frequency is shifted to a frequency in the passband of the intermediate filter, and to input the first intermediate signal to the intermediate filter so as to cause the first intermediate signal to be filtered by the intermediate filter to form a second intermediate signal; a second frequency converter configured to form a cancellation signal by frequency-shifting the second intermediate signal such that a component of the second intermediate signal in the passband of the intermediate filter is shifted to the interferer frequency; and a cancellation unit configured to cancel the cancellation signal from the received signal to attenuate the interferer therein.
|DIGITAL COMMUNICATIONS TEST SYSTEM FOR MULTIPLE INPUT, MULTIPLE OUTPUT (MIMO) SYSTEMS - A digital communications test system and method for testing a plurality of devices under test (DUTs) in which multiple sets of a single vector signal analyzer (VSA) and single vector signal generator (VSG) can be used together to perform error vector magnitude (EVM) measurements for one or more DUTs in parallel, including one or more of composite, switched and multiple input multiple output (MIMO) EVM measurements. This allows N pairs of a VSA and VSG to test N DUTs with N×N MIMO in substantially the sane time as a single VSA and VSG pair can test a single DUT, thereby allowing a substantial increase in testing throughput as compared to that possible with only a single VSA and VSG set.
|DETECTION OF START FRAME DELIMITERS IN A WIRELESS DIGITAL COMMUNICATION SYSTEM - Forward error correction is used in conjunction with detection of a start frame delimiter (SFD) to provide flexibility and to reduce missed instances of an SFD. Candidate SFDs in an incoming signal are identified using a lower-than-normal detection threshold, and corresponding markers are stored in a buffer. For each stored marker, a physical layer header following the candidate SFD is decoded with error-correction techniques, to determine whether uncorrectable errors exist. If so, the candidate is discarded and the next candidate is evaluated. If no uncorrectable errors exist, the candidate is declared a valid SFD, and the remaining signal is decoded. Dual detection thresholds can be employed in networks that permit both error-encoded and non-coded packets. A technique for selecting SFD patterns that facilitate higher performance is also disclosed.
|HDMI SIGNAL ADJUSTING METHOD, HDMI SIGNAL RECEIVING APPARATUS, HDMI SIGNAL TRANSMITTING APPARATUS, AND HDMI SIGNAL PROCESSING SYSTEM - An HDMI signal adjusting method is provided. A method for adjusting an HDMI signal of a high definition multimedia interface (HDMI) signal receiving apparatus includes: setting an equalizer gain for an HDMI signal, receiving an HDMI signal which is adjusted according to signal adjustment information set by an HDMI signal transmitting apparatus from the HDMI signal transmitting apparatus, signal-processing the received HDMI signal according to the set equalizer gain, detecting an error rate of the signal-processed HDMI signal, and transmitting signal adjustment information corresponding to an HDMI signal having a lowest error rate from among a plurality of the signal-processed HDMI signals corresponding to a plurality of different combinations of the equalizer gain and the signal adjustment information to the HDMI signal transmitting apparatus.
|INVERTER-AND-SWITCHED-CAPACITOR-BASED SQUELCH DETECTOR APPARATUS AND METHOD - A squelch detector includes is configured to receive a time-varying differential communication signal, and includes switched capacitors and an inverter configured to provide an indication of whether a level of the received communication signal is above or below a threshold value.
|METHOD, DEVICE AND SYSTEM FOR DETECTING RADIO FREQUENCY INTERFERENCE - A method for detecting radio frequency interference (RFI) is provided. The method includes the following steps. Parameters of at least two pairs of digital subscriber lines (DSLs) are acquired. Sub-carriers having RFI in each pair of the at least two pairs of DSLs are detected according to the parameters. The number of line pairs having RFI on the same sub-carrier in the DSLs is counted, and if the number of the line pairs occurring RFI on the sub-carrier is greater than a preset threshold, or if a ratio of the number of the line pairs occurring RFI on the sub-carrier to a line pair number of the at least two pairs of DSLs is greater than a preset threshold, it is determined that RFI exists at a frequency corresponding to the sub-carrier. A device and a system for detecting RFI are further provided. Therefore, RFI frequency existing in xDSL can be detected.
|RECEIVING APPARATUS - A receiving apparatus has counters
|Identifying An Optimized Test Bit Pattern For Analyzing Electrical Communications Channel Topologies - Identifying an optimized test bit pattern for analyzing electrical communications channel topologies, including: ranking according to channel quality, from worst to best, a set of channel topologies for an electrical communications channel; and for each ranked channel topology beginning with the worst, carrying out the following steps in an iterative loop until a concatenated test bit pattern and a previously optimized test bit pattern are functionally equally fit: concatenating to a previously optimized test bit pattern an additional test bit pattern; optimizing the concatenated test bit pattern values for a next ranked channel in the subset, leaving the optimized values of the previously optimized test bit pattern unchanged; and comparing through use of a fitness function the relative qualities of the previously optimized test bit pattern and the optimized concatenated test bit pattern.
|METHOD FOR BUILDING SETS OF MOBILE STATIONS IN MIMO SYSTEMS, CORRESPONDING MOBILE STATION, BASE STATION, OPERATION AND MAINTENANCE CENTRE AND RADIO COMMUNICATION NETWORK - The invention relates to a method for building sets of mobile stations in a radio communication network (RCS
|Low-1/f-Noise Local Oscillator for Non-Overlapping Differential I/Q Signals - The present invention relates to a circuit arrangement (
|ESTIMATION OF SIGNAL AND INTERFERENCE POWER - Wireless receiver and method of operating a wireless receiver in a wireless communication network for: receiving a signal, the received signal comprising data containing at least one symbol from a symbol alphabet, the symbol alphabet consisting of complex values that define a direction in the complex plane, the received signal further comprising interference; measuring the variance of a first component of the received signal that is perpendicular to the defined direction in the complex plane; estimating the interference power of the received signal using the measured variance of the first component of the received signal; estimating a total power of the received signal; estimating the power of the at least one symbol of the received signal by subtracting the estimated interference power from the estimated total power of the received signal; and based on the estimated interference power and the estimated power of the at least one symbol of the received signal, performing at least one of the steps of: processing the received signal, and generating control information related to the transmission of a further signal from the wireless receiver.
|Close-loop power transmission calibration - A close-loop power calibration algorithm is performed on a wireless communication device to correct power amplifier pre-distortion or PADR correction curves. In addition to peak to average power ratio or PAPR detection techniques, an algorithm or process is implemented that uses a transmitted reference packet, such as an orthogonal frequency domain multiplexing (OFDM) packet. The reference packet is used to learn the linear response of a detector that measures output of the power amplifier. The transmitted packet can include a linear response. The included linear response can determined by subtracting a normal packet from the reference packet.
|MULTI-DOMAIN TEST AND MEASUREMENT INSTRUMENT - A test and measurement instrument including a time domain channel configured to process a first input signal for analysis in a time domain; a frequency domain channel configured to process a second input signal for analysis in a frequency domain; and an acquisition system coupled to the time domain channel and the frequency domain channel. The acquisition system is configured to acquire data from the time domain channel and the frequency domain channel. Time domain and frequency domain data can be time aligned.
|METHOD FOR TRACKING THE PHASE OF A SIGNAL MODULATED BY CONTINUOUS PHASE MODULATION AND SYNCHRONIZATION DEVICE IMPLEMENTING SAID METHOD - A method for tracking the phase of a signal modulated by a continuous phase modulation includes: a complex vector representative of the received signal is determined for each symbol period with an offset of a half symbol period relative to the symbol rate of the receiver; a level measurement is performed on two complex samples distributed with an offset roughly of a half symbol period either side of the instant of estimation of the complex vector; the complex vectors are associated with one of the points of the constellation of the modulation making it possible to find the point which is closest; average estimation of the offset of the phase is calculated by calculating the difference between the average estimation of the phase of the signal and the theoretical phase value associated with each point of the constellation; an absolute estimation and a differential estimation of the offset of the phase is calculated.
|METHODS AND DEVICES FOR UPLINK TRANSMIT DIVERSITY - Methods and devices are described for use in a wireless communications system supporting uplink transmit diversity. If it is detected that a user equipment is currently in one of a predetermined set of situations, a set of restrictions associated with the detected situation is applied when the user equipment changes pre-coding weights. The set of restrictions limits how much the pre-coding weights can be changed. A user equipment in soft handover may also be restricted to only consider feedback information from a serving base station when selecting pre-coding weights. Thus it is possible to ensure that pre-coding weights are carefully selected in situations where there is a high risk for detrimental interference and/or inferior uplink/downlink performance. A network node may be configured to detect such a situation and notify the user equipment of any restrictions to be applied on the pre-coding weight selection.
|LOAD INSENSITIVE QUADRATURE POWER AMPLIFIER POWER DETECTOR - A power detector includes a first phase shift element implemented to shift a phase of a first input signal to generate a first phase-shifted signal, a second phase shift element implemented to alter a phase of a second input signal to generate a second phase-shifted signal, a combiner for combining the first phase-shifted signal and the second phase-shifted signal to generate a combined single-phase signal, and a single element power detector for determining a power of the combined single-phase signal.
|ENCODER - An average quantization error value of each of I, P, and B pictures in an encoded unit of processing is calculated as an actually measured value having a large variation. An average quantization error value of each of I, P, and B pictures in an uncoded unit of processing is set as a target value having a small variation. In the encoding of the uncoded unit of processing, a result of the encoding of the encoded unit of processing is referenced and fed back thereto. By uniformly setting respective quantization errors of images and further by uniformly setting the respective qualities of the images, the image quality of a whole stream can be subjectively improved. Since the prefetch of the uncoded unit of processing is not needed, it is possible to perform real-time processing without any increase in the circuit scale.
|APPARATUS, AND ASSOCIATED METHOD, FOR COMMUNICATING A DATA BLOCK IN A MULTI CARRIER MODULATION COMMUNICATION SCHEME - Apparatus, and an associated method, for sending a data block in an OFDM, or other MCM, communication system with reduced PAPR is provided. The data block is combined with a random scrambling sequence. An IDFT operation is performed upon the combined sequence, and its PAPR, peak-to-average power ratio, is calculated. The PAPR is compared against a threshold. If the PAPR is smaller than a threshold, the transformed, combination sequence is transmitted. Otherwise, a different scrambling sequence, if available, is used to form a new combination sequence, and the process iterates until either a PAPR smaller than the threshold is obtained, or a pre-defined maximum number of iterations is reached. If the maximum number of iterations is reached and no combination sequence is created that leads to an acceptable PAPR, then the transformed, combination sequence that exhibits the smallest PAPR level is selected for transmission.
|DIFFERENTIAL PHASE SHIFT KEYING DEMODULATOR, RECEIVER APPARATUS EMPLOYING THE DEMODULATOR, AND DEMODULATION METHOD - A differential phase shift keying demodulator having an input structured to receive current data representing a current phasor and past data representing at least two past phasors, and a phase differentiator structured to process the current data and reference data representing a reference phasor to provide resulting data representing a phase difference between said current and reference phasors. The differential phase shift keying demodulator also includes a reference phasor computational module configured to generate said reference data basing on said past data representing the at least two past phasors.
|Data Exchange Between Antenna and Modem of Mobile Device - In one embodiment, a method includes accessing data encoding a response shift in a signal received through an antenna of a mobile device. The signal corresponds to wireless communication to the mobile device from another device. The response shift is detected and encoded by a modem of the mobile device coupled to the antenna. The method also includes determining an environmental or operational state of the mobile device based at least in part on the response shift encoded in the data.
|USER APPARATUS AND CELL SEARCH METHOD - A user apparatus for performing cell search includes: a timing information detection unit configured to detect timing information of a synchronization signal transmitted from a connected base station; a secondary synchronization channel correlation detection unit configured to detect a correlation of a secondary synchronization channel included in a synchronization signal transmitted by other base station other than the connected base station by using the timing information detected by the timing information detection unit; and a secondary synchronization channel detection unit configured to detect the secondary synchronization channel based on a result of the correlation detection by the secondary synchronization channel correlation detection unit.
|METHOD AND APPARATUS FOR OBTAINING CHANNEL STATE INFORMATION REQUIRED FOR BEAMFORMING - The present invention provides a method for obtaining channel state information required for beamforming, comprising: estimating current channel state information according to a received signal; predicting future channel state information which is expected to be used by a transmitter in the next beamforming based on the current channel state information and historical channel state information; reading previous channel state information used by the transmitter in the current beamforming; determining feedback information based on the future channel state information and the previous channel state information; and sending the feedback information to the transmitter. The present invention further provides a method for performing beamforming, comprising: receiving feedback information from a receiver; reading previous channel state information used in the last beamforming; reconstructing channel state information based on the feedback information and the previous channel state information; and performing beamforming according to the reconstructed channel state information.
|ANTENNA MEASUREMENT SYSTEM AND METHOD - The present invention relates to an antenna measurement system and a corresponding method for measuring parameters of the transfer function of an antenna transmission system comprising a transmit antenna, a receive antenna and a transmission channel between said transmit antenna and said receive antenna, and/or for measuring parameters of an antenna of said antenna transmission system. In order to enable such a measurement for a single discrete frequency at high frequencies as used in mm-wave applications, an antenna measurement system is proposed comprising mixers, for frequency conversion on the transmitter side and detection on the receiver side, which are both driven by an electromagnetic radiation signal. Applying a switched DC signal for biasing the mixer on the transmitter side with an ultra-fast rise-time, the envelope of the time domain signal can directly be measured in the time domain on the receiver side.
|Techniques for Improving Channel Estimation and Tracking in a Wireless Communication System - A technique for performing channel tracking and/or channel estimation in a wireless communication device includes receiving a reference signal and one or more non-error propagation physical channel signals. In general, the one or more non-error propagation physical channel signals must be correctly decoded before a data channel can be decoded. Channel tracking and/or channel estimation are/is then performed based on the reference signal and at least one of the one or more non-error propagation physical channel signals.
|SYSTEM AND METHOD FOR TESTING A RADIO FREQUENCY (RF) MULTIPLE-INPUT-MULTIPLE-OUTPUT (MIMO) DEVICE UNDER TEST (DUT) - A system and method for testing a radio frequency (RF) multiple-input-multiple-output (MIMO) device under test (DUT) in which system costs are minimized by using fewer precision RF MIMO testing subsystems together with lower precision integrated RF MIMO signal conversion circuitry to test the DUT.
|IDENTIFICATION OF TARGET SIGNALS IN RADIO FREQUENCY PULSED ENVIRONMENTS - A system and method for processing signals are disclosed. The method may be performed, at least partially, by the system. In one embodiment, the method comprises sending a first plurality of data including transmission parameters to a transmission system for transmitting of a first plurality of signals, receiving a second plurality of signals including signals based on the power level of the first plurality of signals, detecting in the second plurality of signals the signals corresponding to the first plurality of signals, outputting a second plurality of data based on the power levels of the second plurality of signals corresponding to the first plurality of signals, and receiving the second plurality of data and associating the first plurality of data and the second plurality of data based on the time when the first plurality of signals was transmitted and the second plurality of signals was received
|Method and System for Monitoring Various Signals in a Continuous Processing Circuit for a Single Channel in a Communication System - A method and system for monitoring includes a transfer switch and a first receiver decoder circuit for a first channel coupled to the first transfer switch. The first receiver decoder circuit generates a first receiver decoder circuit signal. A second receiver decoder circuit for the first channel is coupled to the first transfer switch. The second receiver decoder circuit generates a second receiver decoder circuit signal. A monitoring display is formed in response to the first receiver decoder circuit signal and the second receiver decoder circuit signal.
|METHOD AND APPARATUS FOR CHARACTERIZED PRE-DISTORTION CALIBRATION OF A POWER AMPLIFIER - A method and apparatus for characterized pre-distortion calibration is provided. The method begins with the selection of a number of devices to be characterized. The number of devices selected may be a subset of a larger group of devices. The selected number of devices is then characterized. The method avoids characterizing the large group of devices. The calibration of the group of devices is then based on the characterization of the selected number of devices.
|SYSTEMS AND METHODS FOR DETECTING DATA COLLISIONS FOR A NEAR FIELD COMMUNICATION SYSTEM - In a wireless near field communication (NFC) system, a target, such as a smart card, can communicate with an initiator, such as a card reader, by load modulating a radio frequency (RF) signal generated by the initiator. When two or more targets load modulate the RF signal generated, "collisions" can occur with the load modulation. Apparatus and methods detect the presence or absence of collisions in a lower layer or physical layer and report the presence of detected collisions to an upper layer for further handling.
|Method And Apparatus For Evaluating And Optimizing A Signaling System - A method and apparatus for evaluating and optimizing a signaling system is described. A pattern of test information is generated in a transmit circuit of the system and is transmitted to a receive circuit. A similar pattern of information is generated in the receive circuit and used as a reference. The receive circuit compares the patterns. Any differences between the patterns are observable. In one embodiment, a linear feedback shift register (LFSR) is implemented to produce patterns. An embodiment of the present disclosure may be practiced with various types of signaling systems, including those with single-ended signals and those with differential signals. An embodiment of the present disclosure may be applied to systems communicating a single bit of information on a single conductor at a given time and to systems communicating multiple bits of information on a single conductor simultaneously.
|Process for Performing a QR Decomposition of a Channel Matrix in a MIMO Wireless Communication System, and Receiver for Doing the Same - A process for performing a QR Decomposition of a channel matrix of a wireless communication channel system, said process involving the steps of: performing a full QR Decomposition of one channel matrix for the purpose of deriving a first QR representation of the channel; performing a second iterative QR Decomposition of an adjacent channel matrix, said second iterative QR Decomposition using the results of said first QR representation as well as the difference of the two adjacent channel matrices ΔH. More particularly, the process is characterized in that the iterative QR Decomposition is performed in response to the detection of a high level of workload of the processor.
|WIRELESS COMMUNICATION NETWORK AND A PATH SELECTION METHOD - There was an inconvenience that, at the time of path selection of a wireless communication network which is structured using a wireless equipment including an adaptive modulation system, a path setting considering fluctuation of a transmission capacity caused by a state change of a wireless propagation line in each path by a change of such as the weather could not be performed.
|METHOD AND APPARATUS FOR DETECTING ENVELOPE - A method and apparatus for detecting an envelope are provided. The method and apparatus may detect an envelope of a modulating signal based on a low calculation complexity and a simple circuit configuration, by detecting an envelope for a plurality of sampling signals with equal time intervals.
|METHOD OF MEASURING ERROR VECTOR MAGNITUDE - A method of checking an error vector magnitude of transmitter in accordance with some embodiments of the inventive concept may include dividing a transmission baseband signal which the transmitter transmits into a plurality of processing units; performing a transmitter function and an ideal receiver function with respect to each of the plurality of processing units; generating a reception baseband signal by recombining a processing result of each of the plurality of processing units; and calculating an error vector magnitude (EVM) by comparing the transmission baseband signal with the reception baseband signal.
|METHOD, DEVICE AND SYSTEM FOR UPSTREAM POWER BACK-OFF IN DIGITAL SUBSCRIBER LINE - A method, a device and a system for Upstream Power Back-Off (UPBO) in a Digital Subscriber Line (DSL) are provided. The method includes: collecting subscriber line information (S
|RADIO COMMUNICATION APPARATUS CAPABLE OF SWITCHING MODULATION SCHEMES - A transmitting apparatus includes a modulation signal generating section that generates a modulation signal by modulating transmission data using one of a plurality of modulation schemes. The plurality of modulation schemes include a first modulation scheme, a second modulation scheme, and a third modulation scheme, where the first modulation scheme has maximum m-ary modulation value, the second modulation scheme has a lower m-ary modulation value than the first modulation scheme, and the third modulation scheme has a lower m-ary modulation value than the second modulation scheme. The transmitting apparatus also includes a pilot signal generating section that generates a pilot signal having one of a plurality of amplitudes, the pilot signal having a lower amplitude than a maximum amplitude of the first modulation scheme. The transmitting apparatus further includes a selection section that selects the modulation signal or the pilot signal according to a frame timing signal and generates a transmission quadrature baseband signal, a radio section that converts the transmission quadrature baseband signal to a radio signal, an amplifying section that amplifies the radio signal, and an antenna section that transmits the amplified radio signal.
|TESTING PERFORMANCE OF A WIRELESS DEVICE - Improved performance testing of a wireless device is disclosed. The system is particularly suited to testing devices having multiple antennas. The device under test (DUT) is placed in a reverberation chamber with antennas for transmission of a test signal to the DUT. The number of antennas deployed in the reverberation chamber and placement of those antennas is selected such that no line-of-sight transmission component exists from test system antenna to DUT antenna, and the number of antennas deployed in the reverberation chamber is greater than the spatial rank of the signal. The antennas are driven by a programmable channel emulator capable of generating fading, correlation, delay, Doppler and other channel condition phenomena. Furthermore, the antennas are driven individually by a plurality of independent fading processes. The combination of the programmable channel emulator and reverberation chamber creates a multipath environment which simulates signals arriving from different locations, with different delays, as well as the simulation of device motion. The system also includes instruments to produce test signals and to measure the performance of the DUT.
|METHOD FOR DETECTING OFFSET SIGNAL CORRESPONDING TO TRANSMISSION LEAKAGE SIGNAL - A method for detecting offset signal corresponding to transmission leakage signal is disclosed, whereby reception sensitivity can be improved by accurately offsetting a leakage signal in transmission signal mixedly inputted into the reception signal in a radio transceiver, and an offset signal corresponding to a transmission leakage signal can be rapidly detected in the radio transceiver to rapidly offset the transmission leakage signal included in a reception signal.
|METHOD AND APPARATUS FOR TRANSMITTING SIGNALS, AND METHOD AND APPARATUS FOR RECEIVING THE SIGNALS - A storage unit stores a preamble signal defined in a legacy system and a preamble signal defined in a MIMO system. A monitoring unit in a transmitting apparatus monitors the existence of any communication apparatus which is not compatible with the MIMO system but accepts the legacy system. A channel characteristics acquiring unit derives the characteristics of a radio channel between the transmitting apparatus and a receiving apparatus. A selector selects a packet format based on a monitoring result obtained by the monitoring unit. The selector also selects where to place LTS, based on the characteristics of wireless channel derived by the channel characteristics acquiring unit.
|System And Method For Channel Status Information Feedback In A Wireless Communications System That Utilizes Multiple-Input Multiple-Output (MIMO) Transmission - A method for user equipment operation in a wireless communication system, the wireless communication system having an base station, the method comprising measuring a channel between the UE and the base station, determining a quantized estimate using a codebook to approximate the measured channel, computing an error measure for the quantized estimate and transmitting the error measure and the quantized estimate to the base station for use by the base station in reconstructing an actual channel vector.
|SIGNAL TRANSMITTING METHOD, SIGNAL TRANSMITTING APPARATUS AND SIGNAL TRANSMITTING SYSTEM - A signal transmission method, a signal transmission apparatus, and a signal transmission system are provided. The signal transmission method includes transmitting a test signal via at least one of a plurality of lines included in a channel; receiving transmission state information indicating a state of the transmission of the test signal; and determining whether to change a number of lines to be used for transmitting a main signal based on the transmission state information.
|SERIAL TRANSMISSION APPARATUS, INFORMATION PROCESSING APPARATUS, AND SERIAL TRANSMISSION METHOD - A serial transmission apparatus, which transmits data through a serial communication line, includes a transmission unit configured to transmit data stored in a transmission data buffer to a transmission destination apparatus, a time-out detector configured to detect a time out when a response to the transmitted data from the transmission destination apparatus is not received within a specified period of time, a recovery state detector configured to detect a recovery state representing that the serial communication line is in a link recovery process, and a retransmission request unit configured to request the transmission unit to transmit again the data which has been stored in the transmission data buffer when the time-out detector detects the time-out or when the recovery state detector detects the recovery state of the serial communication line.
|CREST FACTOR REDUCTION METHOD AND CIRCUIT FOR A MULTI-CARRIER SIGNAL - A method for crest factor reduction of a multi-carrier signal is disclosed. The method comprises determining a plurality of signal values of a plurality of single-carrier signals prior to combining the plurality of single-carrier signals to form the multi-carrier signal. The method further comprises performing a joint potential peak detection on the plurality of signal values, producing a temporal position of a possible peak in the multi-carrier signal, generating a plurality of cancellation pulses, and injecting the plurality of cancellation pulses to the plurality of single-carrier signals at temporal injection positions which correspond to the temporal position of the possible peak in the multi-carrier signal. The single-carrier signals are then combined to form a crest factor reduced multi-carrier signal. A corresponding circuit and corresponding computer program product useable during manufacture and operation are also disclosed.
|SELECTIVE COHERENT AND NON-COHERENT DEMODULATION METHODS AND APPARATUSES - Techniques are provided which may be implemented using various methods and/or apparatuses in a receiver of an electronic device to allow for a received signal to be demodulated using both coherent and non-coherent demodulation techniques and for selecting one of the demodulated data signals based, at least in part, on a drift rate measurement of a carrier frequency of the received signal.
|Feedback Receiver for Antenna Tuner Calculations - Some embodiments of the present disclosure relate to a feedback receiver comprising a threshold comparator configured to determine if the amplitude of a baseband signal is within a selection corridor (e.g., defined by an upper and lower threshold value). If the amplitude is within the selection corridor, a feedback receiver is configured to accumulate RF signal samples (e.g., amplitude and phase samples) over a time period. The accumulated RF signal samples, which correspond to substantially constant baseband amplitude values, are then averaged. The calculated averages are utilized for impedance measurements used tune an antenna tuner to limit impedance mismatch. By limiting RF amplitude and phase sample collection to associated baseband signals having an amplitude falling within the selection corridor, substantially equal average amplitudes and phases can be achieved over a relatively short measurement period (i.e., without the need for long measurement period).
|DUMMY PAGING CHANNEL DETECTION - This invention relates to a method and system for detecting a dummy paging channel message. the method includes the steps of: providing a reference dummy paging channel burst sequence; receiving a plurality of raw burst data; comparing every bits of the reference dummy paging channel burst sequence and every bits of a specific raw burst data of the raw burst data to obtain a matching metric according to a comparing result thereof; and determining the raw burst data is a dummy paging channel message if the matching metric is greater than a dummy paging channel threshold value.
|METHOD OF DISPLAYING A DIGITAL SIGNAL - Devices communicate with one another over a wireless channel according to a signal strength of a signal transmitted over the wireless channel. Digital data captured at a source is transmitted over the wireless channel at a first quality if the signal strength or latency is above a threshold and at a second quality if the signal strength or latency is below the threshold. In addition, noise can be inserted into the transmitted digital data as a way to alert the recipient of the signal of signal strength degradation at a finer granularity.
|System and Method for Selecting Parameters for Compressing Coefficients for Nodescale Vectoring - In general, the present invention relates to methods and systems for optimizing the precoder coefficient compression parameters for reducing the storage and other demands on a vectored DSL system. Embodiments of the invention can be implemented in conjunction with various existing coefficient compression techniques such as quantization of coefficients and decimation in frequencies. According to certain aspects, the compression parameters (e.g. Golomb modulus and quantization level) are selected for each of a plurality of macrobands so as to optimize the overall data rate of the system for any given channel condition. According to further aspects, the compression parameters are computed to ensure that the compressed coefficients for all macrobands do not exceed the available memory allocated for storing the coefficient data.
|DYNAMIC GAIN ASSIGNMENT IN ANALOG BASEBBAND CIRCUITS - A system and method is provided for filtering and amplifying a signal where amplification can be distributed between stages of a filter and gain can be assigned throughout the filter to optimize system performance. Such a system can be implemented in the baseband section of RF receivers. VGAs can be implemented between filter stages, such as biquads, or VGAs can be incorporated in filter stages. Substantially linear VGAs comprising a parallel resistor array can be incorporated in the circuitry of the filter stages to reduce distortion. Gain can be assigned dynamically in the amplification stages to improve noise and/or linearity performance. For example, gain assignments can be implemented so that high power undesired signal components are filtered out before amplification to prevent component saturation, and low power signals are amplified before they are filtered to improve noise performance.
|METHOD FOR DETECTING LEAKAGE IN DIGITALLY MODULATED SYSTEMS - In a method for detecting leakage in a digital cable system, at least one first signal is inserted on the cable system. The at least one first signal has an amplitude multiple tens of dB below the digital channel power of the digital channels carried on the cable system. A second signal containing the first signal is received. The second signal is converted to an intermediate frequency (IF) signal. The IF signal is digitized and samples of the digitized IF signal are obtained. Digitized samples of a third signal at the nominal frequency of the first signal at maximum amplitude converted to the IF are provided. The digitized IF signal and the digitized samples of a third signal at the nominal frequency of the first signal at maximum amplitude converted to the IF are correlated. The presence of the inserted first signal is detected based upon the result of the correlation. In another method, a pair of first signals are inserted on the cable system. The pair of first signals are spaced apart a fixed frequency and with amplitudes multiple tens of dB below the digital channel power of the digital channels carried on the cable system. A second signal containing the first signal is received and converted to an intermediate frequency (IF) signal. The IF signal is digitized, samples of the digitized IF signal are obtained, and a large scale Fast Fourier Transform (FFT) is applied to the samples to generate an FFT output. The FFT output is examined for generally equally sized signals separated from each other by the fixed frequency in the FFT output. If generally equally sized signals separated from each other by the fixed frequency are detected in the FFT output, a decision is made that the second signal represents detected leakage from the digital cable system.
|METHOD AND APPARATUS FOR ACQUIRING ESTIMATED VALUE OF TRANSMITTED SIGNAL AND A SYSTEM-ON-CHIP - The embodiments of the disclosure disclose a method and an apparatus for acquiring estimated values of transmitted signals, and a system-on-chip. The method comprises: in response to the sequence number N of a current OFDM symbol between sequence numbers N1 and N2 that are sequence numbers of two adjacent OFDM symbols containing pilots, for each RE within the Nth OFDM symbol, instantaneously acquiring a channel estimation value C
|MEASURING SATELLITE LINEARITY FROM EARTH USING A LOW DUTY CYCLE PULSED MICROWAVE SIGNAL - System for measuring satellite downlink amplifier linearity includes a pulsed signal generator for selectively generating low duty cycle pulses. A linear transmitter uplink amplifier is provided for amplifying the low duty cycle pulses and generating an uplink signal. An antenna transmits the amplified uplink signal to an orbiting satellite. A downlink amplifier in the satellite generates a downlink signal for re-transmission to an Earth-based antenna. A pulse receiver is provided for receiving the downlink signal and providing information regarding the transfer function of the downlink amplifier. Preferably, a delayed trigger circuit is coupled to the pulse signal generator for activating the pulsed signal generator after a time delay substantially corresponding to the propagation times of the uplink and downlink signals. By altering the duty cycles of the uplink signals while maintaining the peak power level the average powers transmitted to the downlink amplifiers can be changed to modify the power levels of the downlink signals to provide more complete information regarding the transfer functions of the downlink amplifiers.
|Adaptive Compensation of Nonlinear Frequency Distortion in Polar Transmitters Based on a Least Squares Estimation - The present invention relates to a communication system having a digital to analog converter, a first input, a summation component, and a compensation unit. The converter is configured to receive a first. The first input is configured to receive a phase modulation signal. The compensation unit includes one or more inputs and is configured to measure amplitude samples of the first signal at a first of the one or more inputs and to generate a correction signal according to the one or more inputs. The correction signal at least partially accounts for estimated distortions of the phase modulation signal from the amplitude modulation path. The summation component is configured to receive the phase modulation signal and the correction signal and to generate a corrected phase modulation signal as a result.
|SIGNAL-SENSITIVE DATA COMPRESSION - A test and measurement instrument includes an input for receiving an input test signal and a separator that separates a data array of the input test signal into a number of different data bins. Each data bin includes a number of data points. A selector is included that determines whether the data points within a present bin of the total bins represent signal or noise. When the present bin contains noise, a processor generates a first output for the present bin. Instead, when the present bin contains signal, the processor generates a second output for the present bin. The bin outputs can then be combined to make an output array, such as a waveform display, for the instrument.
|Antenna Activity Detection in Multi-Antenna Communication - The present subject matter discloses a method for antenna activity detection in multi-antenna communication devices. In one embodiment, the method comprises computing a received signal strength indicator (RSSI) value for each of a plurality of antennas based on a sampled data associated with each of the antennas. The RSSI values may then be analyzed to identify an antenna having a highest RSSI value as a primary antenna and one or more antennas having the RSSI value less than the highest RSSI value as auxiliary antennas. Further, an RSSI difference for each of the auxiliary antennas is calculated and compared with a first threshold value to ascertain one or more potentially inactive antennas from among the auxiliary antennas. The potentially inactive antennas may then be further analyzed to identify one or more inactive antennas based at least in part on the RSSI value.
|APPARATUS AND METHOD FOR BEAMFORMING GAIN DIFFERENCE COMPENSATION ACCORDING TO CHANGE OF TRANSMITTING AND RECEIVING BEAM PATTERN IN BEAMFORMING BASED WIRELESS COMMUNICATION SYSTEM - A method of operating a Mobile Station (MS) in a wireless communication system using beamforming includes receiving a reference signal over a plurality of downlink transmit (Tx) beams, measuring channel quality information of the received reference signal, and generating effective channel quality information by compensating for beamforming gain compensation information according to the channel quality information.
|Method and Procedure for Detecting Cable Length in a Storage Subsystem with Wide Ports - A mechanism detects cable length in a storage subsystem with wide ports. The mechanism uses in-situ bidirectional cable wrapping for determining different cable lengths. The mechanism under-margins transmitter output to failure for each external port and even for each PHY within a wide port. Based on the transition point from "good" wrap to "bad" wrap, the cable length may be determined. The transition point identifies if the cable is long or short, at which point the optimum tuning parameters can accordingly be set. A calibration mechanism calibrates the high speed transmitter/receiver pair characteristics, and, thus, optimizes the transmission performance between subsystems. The calibration mechanism mitigates the need for frequent error correction and does not incur the performance degradation associated with error correction techniques.
|SIGNAL STRENGTH ESTIMATION SYSTEM AND METHOD - A signal strength estimation circuit for a code division multiple access system comprises a channel compensator, a demodulator, an extractor and an average circuit. The channel compensator compensates different channel effect upon a received signal and outputs first and second compensated signals wherein the received signal comprises a first signal and a second signal. The demodulator electrically connected to the channel compensator demodulates the first and second compensated signals and outputs first and second demodulated signals wherein the demodulator demodulates the first and second compensated signals by corresponding 4 bits pilot patterns when each of the first and second compensated signals only has 2 pilot bits in a slot and the second signal is obtained by space time transmit diversity encoding the first signal. The extractor coupled to the demodulator respectively extracts first and second pilot signals from the first and second demodulated signals. The average circuit coupled to the extractor averages the first and second pilot signals, thereby obtaining a signal strength estimation.
|Methods and Systems for Near-Field MIMO Communications - A near-field communication (NFC) system supports increased data rates using a multiple-input-multiple-output (MIMO) interface. Multiple receive antennas are positioned within the near field of multiple transmit antennas. The NFC system uses a combination of antenna spacing and polarizations to reduce correlation between channels, and thus improves performance by creating closer to ideal MIMO operation. Such system can also be operated as parallel SISO links with reduced cross-channel interference resulting in low power consumption.
|Relative Phase Detection in Power Line Communications Networks - Systems and methods for relative phase detection and zero crossing detection for power line communications (PLC) are described. In some embodiments, both transmit and receive PLC devices detect a zero crossing on an AC mains phase. The devices start a phase detection counter (PDC) by generating a zero crossing pulse within 5% of the actual zero crossing time. When a frame is transmitted, the transmitting device includes a PDC value in the frame control header (FCH). The PDC value corresponds to the start time of the FCH. When the frame is received at the receive PLC device, the receive PLC device measures a local PDC value between the zero crossing and the start of the FCH. The receive device compares the local PDC value to the PDC value in the FCH of the received frame and determines if the devices are on the same phase.
|SYSTEM AND METHOD OF MAINTAINING CORRECTION OF DC OFFSETS IN FREQUENCY DOWN-CONVERTED DATA SIGNALS - Circuitry and method for reduce test time for wireless signal systems by using dynamic adaptive correction of DC offsets generated by the test instrument. The data signal is sampled for downstream processing including during pre-, inter-, or post-packet time intervals where no packet-data signal is occurring and where the device's power amplifier is turned off. The sampled data signal is measured for a DC offset occurring during these inter-packet time gaps. Compensating DC offset values are stored in a table indexed by frequency, gain and temperature range. When a subsequent test is carried out at that frequency, gain, and temperature range, the stored compensation value is used to correct the signal. DC offsets continue to be measured, stored and applied to captured signals, continuously refining the compensation values and decreasing the need for time-intensive calibrations. When a measured DC offset exceeds pre-determined limits, the instrument undergo a calibration step.
|Mechanism for the Measurement of DC Properties of a Signal Path - Systems and methods for measuring transmitter and/or receiver I/Q impairments are disclosed, including iterative methods for measuring transmitter I/Q impairments using shared local oscillators, iterative methods for measuring transmitter I/Q impairments using intentionally-offset local oscillators, and methods for measuring receiver I/Q impairments. Also disclosed are methods for computing I/Q impairments from a sampled complex signal, methods for computing DC properties of a signal path between the transmitter and receiver, and methods for transforming I/Q impairments through a linear system.
|Measurement of I/Q Impairments from a Sampled Complex Signal - Systems and methods for measuring transmitter and/or receiver I/Q impairments are disclosed, including iterative methods for measuring transmitter I/Q impairments using shared local oscillators, iterative methods for measuring transmitter I/Q impairments using intentionally-offset local oscillators, and methods for measuring receiver I/Q impairments. Also disclosed are methods for computing I/Q impairments from a sampled complex signal, methods for computing DC properties of a signal path between the transmitter and receiver, and methods for transforming I/Q impairments through a linear system.
|AUTOMATED ERASURE SLICER THRESHOLD CONTROL AND MODIFICATION OF SYMBOL ESTIMATES TO BE ERASED - Methods and systems to vary an erasure slicer threshold based on a measure computed from prior soft and/or hard symbol decisions, identify reliable symbol estimates based on the threshold, identify unreliable symbol estimates for erasure based on the threshold, modify the identified symbol estimates, output the reliable symbol estimates and the modified symbol estimates as erasure slicer decisions, and filter the decisions in a feedback filter of a decision feedback equalizer (DFE). The erasure slicer threshold may be based on signal-to-noise ratio (SNR) or mean-squared-error (MSE). A symbol estimate may be identified for erasure when a coordinate of the corresponding soft decision is within an erasure area defined by the threshold. Symbol modification may include replacing a corresponding coordinate of the symbol estimate with a coordinate of a decision boundary associated with the erasure area.
|Fully-Digital BIST for RF Receivers - A built-in receiver self-test system provides on-chip testing with minimal change to the receiver footprint. The system digitally generates a two-tone test signal, and tests the nonlinearities of the receiver using the generated two-tone test signal. To that end, the self-test system comprises a stimulus generator, a downconverter, and a demodulator, all of which are disposed on a common receiver chip. The stimulus generator generates a test signal comprising first and second tones at respective first and second frequencies, where the first and second frequencies are spaced by an offset frequency, and where the first frequency comprises a non-integer multiple of the offset frequency. The downcoverter downconverts the test signal to generate an In-phase component and a Quadrature component. The demodulator measures an amplitude of the intermodulation tone by demodulating the In-phase and Quadrature components based on a reference frequency.
|DEVICE, METHOD, AND PROGRAM FOR SIGNAL ANALYSIS, AND RECORDING MEDIUM - The time required for analyzing a modulation accuracy of a modulated signal is reduced. A signal analyzing device which analyzes a signal to be measured including multiple frames each of which includes a preamble and a data symbol, includes frame acquisition units which acquire the frame from the signal to be measured, a symbol demodulation unit which demodulates the acquired frame according to symbol demodulation, and a modulation accuracy deriving unit which derives a modulation accuracy based on an output from the symbol demodulation unit, where the frame acquisition unit considers a position displaced by an integer multiple of the length of the frame from a start frame positioned at a start of the signal to be measured as a position of a subsequent frame positioned after the start frame, and acquires the subsequent frame.
|RADIO CHANNEL DATA AND THE USE THEREOF - Apparatus comprises a receiver receiving wireless transmission of a real radio system from at least one base station of a radio system as a function of reception direction. The transmission comprises predetermined data. The apparatus comprises also a processing unit that forms taps of a delay profile on the basis of comparison between the data that is received and corresponding predetermined data. The processing unit estimates direction for the taps of the delay profile on the basis of a reception direction of the transmission, and forms radio channel data by associating the taps of the delay profile with the estimated direction. The radio channel data is for a radio channel model of a MIMO emulation in an OTA chamber having a plurality of antennas around a test zone where a device-under-test may be placed.
|INFERRING PRESENCE AND IDENTITY OF NON-LINEAR DEVICES ON A POWERLINE COMMUNICATION NETWORK - A non-liner device (NLD) between powerline communication (PLC) devices can introduce significant distortion into the channel being utilized by the PLC devices. This distortion can create errors and corrupt data transmitted by the PLC devices. When trying to mitigate the effects of the distortion introduced by NLDs, PLC devices conform their mitigating actions to effectively satisfy a limit(s) set by a regulation and/or a standard. A PLC device implemented in accordance with this disclosure can mitigate the distortion effects with deference to regulatory/standard limits without knowledge of what types of NLDs and how many NLDs are coupled to the power line. A PLC device can use different techniques to infer the presence of an NLD in a PLC network. A PLC device can infer the presence of the NLD using a passive technique or one or more active techniques.
|Method and System for Diagnosing Radio Performance During Functional Over-the-Air Operation - An apparatus for determining a health of radio-frequency transmitters each transmitting a transmitted signal during normal operation. The apparatus comprises a receiver for receiving received signals, each received signal responsive to a transmitted signal, a first element for determining signal parameters of each received signal, the signal parameters responsive to an operating condition of a transmitter, each transmitted signal and each associated received signal including an identifier of the transmitter that transmitted the transmitted signal, the apparatus using the identifier to link determined signal parameters with the transmitter that transmitted the transmitted signal and a second element for determining a health of the transmitter that transmitted the transmitted signal, the health responsive to a relationship between one or more signal parameters and a selected value or a range of selected values for each signal parameter.
|SYSTEMS AND METHODS FOR LOOP LENGTH AND BRIDGED TAP LENGTH DETERMINATION OF A TRANSMISSION LINE - Through the use of a least squares minimization concept, the loop length, the number of bridged taps and length of the bridged taps on a transmission line can be determined from readily available modem data. In particular, the loop length, the number of bridge taps and the length of bridged taps can be estimated by comparing a measured frequency domain channel impulse response of the transmission line to a model of a loop that is comprised of multiple sections and multiple bridge taps.
|Test Signal in Receiver - The invention proposes a way of inserting an analog test signal during normal reception into analog blocks of an OFDM receiver in such a way that the reception is either not corrupted at all, or only very little. This is achieved either by inserting the analog test signal in time or frequency where it does not corrupt the received signal, or by accounting for the interfering analog test signal in the decoding process.
|Adaptive Smoothing of Channel Estimates - Techniques for directly adapting the parameters of a smoothing filter used for channel estimation to the current velocity and signal-to-noise ratio (SNR) situation. An example method begins with a plurality of channel response measurements. For each of a first subset of a set of pre-determined filter responses, the channel measurement samples are filtered to obtain a corresponding set of estimated channel response samples. Next, for each set of estimated channel response samples, a corresponding set of ordered residuals are calculated from the channel measurement samples. Each set of ordered residuals is evaluated to determine a measure of correlation among the ordered residuals, and an updated filter response is selected from a second subset of the set of pre-determined filter responses, based on this evaluation, for use in demodulating a received signal.
|ADAPTIVE DETECTOR THRESHOLD COMPENSATION IN BINARY FRAME BASED COMMUNICATION SYSTEMS - Various exemplary embodiments relate to a method of producing adaptive thresholds in a binary frame based communication system, including: collecting Kst samples of a received signal corresponding to a start bit; computing an estimate of as received signal parameter Pst in the start bit; adjusting an start threshold based upon Pst; collecting Ksp samples of the received signal corresponding to a stop bit; computing an estimate of a received signal parameter Psp in the stop bit; and adjusting an stop threshold based upon Psp.
|MULTIPLE RECEIVERS IN AN OFDM/OFDMA COMMUNICATION SYSTEM - A signal receiver is configured to receive multiple time-domain input signals. A plurality of the input signals among the multiple time-domain input signals is selected and transformed into frequency-domain signals. The frequency-domain signals are shifted in phase by a negative value of a respective reference phase, and the phase-shifted signals are combined into one signal. The combined signal is then multiplied with a stored signal to generate a signal product and transformed into a time-domain signal. Peak detection is performed on the time-domain signal.
|Methods and Systems for Self-Referencing Single-Ended Signals - A single-ended receiver compares signal levels representing current symbols to levels representing immediately preceding symbols to resolve the symbols. The receiver applies offsets selected based on resolved prior symbols to interpret successive like-symbols.
|SIGNAL SELECTING CIRCUIT AND SIGNAL SELECTING METHOD - A signal selecting circuit according to the present invention includes an abnormality detection circuit that detects an abnormality of the signal input as the main signal in an input stage, a select circuit that selects and outputs the signal input as the main signal among the plurality of signals in the normal state, and when the abnormality detection circuit detects an abnormality of the signal input as the main signal, selects and outputs the signal input as the reserve signal, and a delay circuit that delays the signal input as the main signal by a delay time and outputs the delayed signal to the select circuit, the delay time being equal to or greater than a total time of a detection time in the abnormality detection circuit and a signal switching time in the select circuit.
|METHOD AND APPARATUS FOR IMPROVED PARALLEL RF TESTING OF MULTIPLE DEVICES - A system for parallel radio frequency (RF) testing. The system includes a plurality of signal generators, a plurality of signal analyzers, a data bus connected to the plurality of signal generators, and a controller. The controller has a connection to the data bus so as to be in electronic communication with the plurality of signal generators, and has a plurality of point to point links to respective ones of the signal analyzers so as to be in electronic communication with the plurality of signal analyzers.
|DATA PROCESSING DEVICE AND METHOD FOR ANALYZING STABILITY OF DATA PROCESSING DEVICE - In a data processing device and a method for analyzing stability of the data processing device, one or more sets of equalization parameters and a predetermined bit error ratio (BER) are received. Times and voltages of data points that represent a waveform of an electronic signal generated by the data processing device are read, and an output type of the electronic signal is selected to obtain a time interval of outputs of the electronic signal. Optimal equalization parameters are selected from the one or more sets of equalization parameters to compute a sample interval. Interfering voltages of the electronic signal are computed to select a frequency which is equal to the predetermined BER, and the interfering voltages corresponding to the selected frequency are obtained. An eye pattern is established using the interfering voltages corresponding to the selected frequency, and a determination is made according to the eye pattern.
|METHOD AND APPARATUS FOR SIMULTANEOUS RF TESTING OF MULTIPLE DEVICES IN SPECIFIC FREQUENCY BANDS - A system employing vector signal generator (VSG) and vector signal analyzer (VSA) modules or cards that are configured to test multiple devices under test simultaneously. Each VSG is configured to generate multiple RF test signals and send them to multiple devices under test simultaneously. Similarly, each VSA is configured with multiple signal receiving modules connected to a single controller or memory. Each signal receiving module receives an RF signal from a device under test, converts it to a baseband digital signal, and transmits this digital signal to the VSA's memory. A single RF testing system can employ multiple such VSGs and VSAs, each capable of evaluating multiple devices under test. Each VSG/VSA can further be tuned for operation in discrete or defined frequency bands, which are narrower than those for conventional RF testers, and which can correspond to various wireless standards.
|METHOD FOR DIGITAL WIRELESS COMMUNICATIONS - In a multivalue modulation type with one pilot symbol inserted for every 3 or more symbols, signal points of each one symbol immediately before and after a pilot symbol are modulated using a modulation type different from that for pilot symbols. In this way, it is possible to suppress deterioration of the accuracy in estimating the reference phase and amount of frequency offset by pilot symbols and improve the bit error rate characteristic in the signal to noise ratio in quasi-coherent detection with symbols whose symbol synchronization is not completely established.
|CHANNEL STATE INFORMATION FEEDBACK IN COORDINATED MULTI-POINT SYSTEM - Embodiments of the present disclosure describe devices, methods, computer-readable media and systems configurations for communication of channel state information among network entities. In various embodiments, may calculate first-, second- and third-stage channel state information for nodes of a coordinated multipoint measurement set. Other embodiments may be described and/or claimed.
|METHOD AND APPARATUS FOR DETECTING IMPROPER CONNECTIONS NEAR A CUSTOMER PREMISES EQUIPMENT - According to certain aspects, embodiments of the invention relate to methods and apparatuses to detect loss of connectivity due to improper connection near the CPE modem (i.e. small loop condition) based on the analysis of SELT. In embodiments, this condition is detected based on separately analyzing the location and levels of time domain signals associated with different transmission bands in an xDSL bandplan.
|NON-INSTRUSIVE NETWORK SURVEILLANCE AND CHARACTERIZATION - In a system (
|METHOD AND SYSTEM FOR ADAPTIVELY IDENTIFYING SIGNAL BANDWIDTH - The present invention discloses a method and system for adaptively identifying signal bandwidth. The method includes: performing digitizing intermediate frequency processing to the received signal and outputting in-phase/quadrature (I/Q) signals; identifying signal bandwidth of the I/Q signals according to at least two signal identification templates and outputting the synchronized signal flows after a successful identification. A system for adaptively identifying signal bandwidth is also disclosed. The present invention can be compatible with at least two bandwidth modes, and the software can automatically perform identification and switch of the modulation bandwidth, when manual invention is not necessary and the operation is simple.
|Systems and methods for enhancing spectral efficiency in a communication network - A communication system configured to enhance communication spectral efficiency while maintaining an acceptable level of system robustness. Various combinations of modulation, code rate, and antenna usage scheme, are combined to create a hierarchy of modulation and communication schemes (MCS), such that each higher MCS level represents an enhanced degree of spectral efficiency, traded off for a lowered degree of system robustness. Included also are embodiments of methods testing the quality of data transmission and reception at difference MCS levels, and then raising or lowering MCS levels in order to enhance communication spectral efficiency while not falling below the minimally acceptable level of system robustness.
|SYSTEM AND METHOD FOR ANALYZING A NETWORK - System and methods for analyzing a network are disclosed. One method can comprise determining a parameter for each of a plurality of devices, generating a signature for each of the plurality of devices based upon the determined parameters, comparing the signatures of two or more of the plurality of devices, and grouping the plurality of devices based upon the comparison of the signatures of the two or more of the plurality of devices.
|NOISE INGRESS DETECTION - Methods and systems are provided for detection of noise ingress into a network. In an aspect, multiple access devices on the network are analyzed for noise ingress. In another aspect, using characterization data of components in the network and the detection of the noise at the access devices, the location of the noise ingress can be determined.
|DEVICE FOR AUTO BAUD RATE DETECTION - A device for auto baud rate detection includes an edge trigger, a counter, at least one register and a central processing unit. The edge trigger detects whether a potential of a transmitted signal is raising or falling. The counter is connected to the edge trigger and uses the edge trigger to count pulse widths of the transmitted signal. The register is connected to the counter and stores the pulse widths. The central processing unit is connected to the register, compares the pulse widths so as to identify a minimal pulse width, and calculates a baud rate according to the minimal pulse width by using a probability density function. Thereby, the device is advantageous for lowering hardware costs, increasing use flexibility, reducing configuration limitation and ensuring accurate baud rate detection.
|Time Domain Reflectometry Step to S-Parameter Conversion - A method and apparatus are provided for calculating s-parameters of a device under test from step waveforms acquired by a time domain network analyzer.
|Method for Identifying Signals of the Same Origin - A method for identifying signals of the same origin is described. The signals are identified based upon a method of system analysis, wherein an accumulated value of an attenuation weighted by power of an incoming channel, the so-called correspondence coefficient, is used as the criterion whether two signals are of the same origin.
|Systems and Methods for Advanced Iterative Decoding and Channel Estimation of Concatenated Coding Systems - Systems and methods for decoding block and concatenated codes are provided. These include advanced iterative decoding techniques based on belief propagation algorithms, with particular advantages when applied to codes having higher density parity check matrices. Improvements are also provided for performing channel state information estimation including the use of optimum filter lengths based on channel selectivity and adaptive decision-directed channel estimation. These improvements enhance the performance of various communication systems and consumer electronics. Particular improvements are also provided for decoding HD Radio signals, including enhanced decoding of reference subcarriers based on soft-diversity combining, joint enhanced channel state information estimation, as well as iterative soft-input soft-output and list decoding of convolutional codes and Reed-Solomon codes. These and other improvements enhance the decoding of different logical channels in HD Radio systems.
|PATTERN-BASED LOSS OF SIGNAL DETECTOR - In described embodiments, data pattern-based detection of loss of signal (LOS) is employed for a receive path of serializer/deserializer (SerDes) devices. Pattern-based LOS detection allows for detection of data loss over variety of types of connection media, and is generally insensitive to signal attenuation. More specifically, some described embodiments disclose reliable pattern-based detection of LOS across different connection media for incoming receive data when discreet time decision feedback equalization (DFE) is employed.
|METHOD FOR DETERMINING THE IMPERFECTIONS OF A TRANSMIT PATHWAY AND OF A RECEIVE PATHWAY OF AN APPARATUS, AND ASSOCIATED RADIO APPARATUS - A method is provided for determining the imperfections of a transmit pathway and of a receive pathway of an apparatus, and associated radio apparatus, the transmit pathway comprising a first device for frequency transposition of an analogue sequence to an analogue signal, using a first transposition frequency, the receive pathway comprising a second device for frequency transposition of an analogue signal to an analogue sequence, using a second transposition frequency different from the first transposition frequency.
|SIGNAL ANALYSIS DEVICE, SYNCHRONIZATION SYSTEM, AND SYNCHRONIZATION METHOD - The signal analysis device includes a synchronization data generation unit
|SELF-TEST USING INTERNAL FEEDBACK FOR TRANSMIT SIGNAL QUALITY ESTIMATION - A method, an apparatus, and a computer program product for wireless communication are provided. The apparatus correlates the feedback signal to a reference transmit signal to correct time misalignments between the transmit chain and the feedback loop, wherein the reference transmit signal is generated in digital domain at an input to a transmit chain and estimates a transmit signal quality value based on the correlation.
|Systems And Methods For Adaptive Polarization Transmission - The present invention describes methods and apparatus for adaptive polarization transmission. An exemplary embodiment of the present invention provides an adaptive polarization transmission method. The method includes the step of analyzing at a transmitter device a first set of polarization state information relating to a first wireless signal path. Furthermore, the method includes the step of adapting a transmission signal to be distributed by the transmitter device based on at least the first set of polarization state information.
|Method For Channel Estimation In Vehicle-To-Environment Communication And Communication Device Arranged Therefor - The invention relates to a method and a correspondingly arranged communication device for channel estimation in vehicle-to-environment communication, wherein a model of the environment influencing the vehicle-to-environment communication is produced from parameters of a vehicle-to-environment communication and the quality of the model for the environment is ascertained by the convergence of the parameters used in the model. The course of the convergence of the parameters in the model is monitored and conclusions are drawn with regard to the environment from the course of the convergence of the parameters.
|Margin Test Methods and Circuits - Described are methods and circuits for margin testing digital receivers. These methods and circuits prevent margins from collapsing in response to erroneously received data, and can thus be used in receivers that employ historical data to reduce intersymbol interference (ISI). Some embodiments detect receive errors for input data streams of unknown patterns, and can thus be used for in-system margin testing. Such systems can be adapted to dynamically alter system parameters during device operation to maintain adequate margins despite fluctuations in the system noise environment due to e.g. temperature and supply-voltage changes. Also described are methods of plotting and interpreting filtered and unfiltered error data generated by the disclosed methods and circuits. Some embodiments filter error data to facilitate pattern-specific margin testing.
|ADAPTIVE OFF-CHANNEL DETECTOR FOR RECEIVERS - Receivers (
|CHANNEL ESTIMATION FOR AN OFDM COMMUNICAITON SYSTEM WITH INACTIVE SUBBANDS - For channel estimation in a spectrally shaped wireless communication system, an initial frequency response estimate is obtained for a first set of P uniformly spaced subbands (1) based on pilot symbols received on a second set of subbands used for pilot transmission and (2) using extrapolation and/or interpolation, where P is a power of two. A channel impulse response estimate is obtained by performing a P-point IFFT on the initial frequency response estimate. A final frequency response estimate for N total subbands is derived by (1) setting low quality taps for the channel impulse response estimate to zero, (2) zero-padding the channel impulse response estimate to length N, and (3) performing an N-point FFT on the zero-padded channel impulse response estimate. The channel frequency/impulse response estimate may be filtered to obtain a higher quality channel estimate.
|Method And Apparatus To Track Gain Variation In Orthogonal Frequency Division Multiplexing (OFDM)Systems - Gain variations during a packet can lead to significant performance degradation in communications systems that use high order quadrature amplitude modulation (QAM). A method and the associated apparatus track such variations in an OFDM system and completely eliminate any performance degradation. Gain estimation and compensation is employed with the use of pilot subcarriers in the payload of an OFDM data packet. Estimated pilot magnitude ratios are averaged, throughout the processing life of a packet, to yield accurate gain estimations. A gain compensation factor is used to adjust data carriers. An exclusion method is also employed to eliminate pilot carriers which contribute to noise.
|Enhancing Channel Estimates Made in Digital Communications Receivers - Schemes for combining channel-estimates from different OFDM frames after compensating for changes in receiver-transmitter characteristics.
|ANTENNA ARRAY CONTROL METHOD AND ACCESS POINT USING THE SAME - An antenna array control method is illustrated. At least a packet is selected as at least a probing packet every probing period. One radiation pattern in a probing radiation pattern set is used to transmit the probing packet. The radiation pattern with the minimum packet error rate among all radiation patterns is selected as a best radiation pattern. When the probing period expires, a candidate radiation pattern set is obtained according to current probabilities of the radiation patterns to be the best radiation pattern. Transfer probabilities of the radiation patterns in the candidate radiation pattern set are obtained. A target radiation pattern set is obtained according to the transfer probabilities, a motion variation and trend set, and the candidate radiation pattern set. The probing period and the probing radiation pattern set are adjusted according to whether the target radiation pattern set equals to the probing radiation pattern set.
|MEASUREMENT OF DC OFFSETS IN IQ MODULATORS - Described are systems and methods of determining DC offset voltages in IQ modulators. First, two different DC test voltages are selected for one of the inputs to the IQ modulator. Then, a first test voltage is applied to one input to the IQ modulator while test data is generated by measuring outputs from a set of signals applied to the other input to the IQ modulator. Then the second test voltage is applied and another set of test data generated. From the first and second sets of test data, second-order polynomial functions may be constructed and compared to one another to yield a ratio of power value outputs. Then the DC offset voltages may be determined from the ratio of power value outputs.
|LOSS OF SIGNAL DETECTION FOR HIGH-SPEED SERIAL LINKS - In one embodiment, a loss-of-signal detector is provided that is immune to variations in common mode voltage for a received differential input signal. The loss-of-signal detector is configured is to use a reference voltage that depends upon the common mode voltage.
|NEAR-FIELD MIMO WIRELESS TRANSMIT POWER MEASUREMENT TEST SYSTEMS, STRUCTURES, AND PROCESSES - Systems, processes, and structures provide near-field transmit power measurement for MIMO wireless devices (DUT), such as for any of product development, product verification, and/or production testing. A test signal, such as comprising a pulse train signal, is provided to a MIMO device under test (DUT), wherein portions of the test signal controllably steered and sequentially transmitted from each of the device antennas, to one or more test antennas that are positioned in close proximity to the MIMO DUT. The near-field power of the received test signals is measured, to quickly and efficiently determine if one or more data streams of the MIMO DUT has a problem.
|TECHNIQUES USING DIFFERENTIAL PRECODING FOR HIGHLY CORRELATED CHANNELS IN WIRELESS NETWORKS - An embodiment of the present invention provides a method of using differential precoding feedback for correlated channels, comprising, transmitting by a mobile station (MS) as feedback an index angle for a differential discrete Fourier transform (DFT) codeword corresponding to a shift of a dominant beam represented by a base codeword, where the feedback corresponds to a precoding vector V(t)=Q({circumflex over (θ)}) for index angle θ, where
|Channel Estimation - Methods and devices related to channel estimation for a communication system comprising a plurality of communication connections are provided. For channel estimation, test sequences are used having three different elements, for example −1, 0 and +1.
|Receiver with Enhanced DC Compensation - The disclosure relates to a receiver system that employs multiple instances of a DC compensation system to reduce DC offsets in a receiver path. The receiver has a receiver front end configured to receive an RF input signal and to operate on the RF input signal according to a plurality of receiver states to generate a baseband signal having a DC offset that is based upon the plurality of receiver states. A DC offset compensation circuit implements a plurality of instances of DC offset compensation components that respectively generate an estimated DC offset corresponding to a receiver state. A controller controls the receiver state of the receiver front end and operates the DC offset elimination circuit to selectively apply one of the plurality of DC compensation components to the corresponding baseband signal based upon the receiver state.
|Method And Apparatus For Evaluating And Optimizing A Signaling System - A method and apparatus for evaluating and optimizing a signaling system is described. A pattern of test information is generated in a transmit circuit of the system and is transmitted to a receive circuit. A similar pattern of information is generated in the receive circuit and used as a reference. The receive circuit compares the patterns. Any differences between the patterns are observable. In one embodiment, a linear feedback shift register (LFSR) is implemented to produce patterns. An embodiment of the present disclosure may be practiced with various types of signaling systems, including those with single-ended signals and those with differential signals. An embodiment of the present disclosure may be applied to systems communicating a single bit of information on a single conductor at a given time and to systems communicating multiple bits of information on a single conductor simultaneously.
|Method And Apparatus For Evaluating And Optimizing A Signaling System - A method and apparatus for evaluating and optimizing a signaling system is described. A pattern of test information is generated in a transmit circuit of the system and is transmitted to a receive circuit. A similar pattern of information is generated in the receive circuit and used as a reference. The receive circuit compares the patterns. Any differences between the patterns are observable. In one embodiment, a linear feedback shift register (LFSR) is implemented to produce patterns. An embodiment of the present disclosure may be practiced with various types of signaling systems, including those with single-ended signals and those with differential signals. An embodiment of the present disclosure may be applied to systems communicating a single bit of information on a single conductor at a given time and to systems communicating multiple bits of information on a single conductor simultaneously.
|HIGH SPEED SIGNALING SYSTEM WITH ADAPTIVE TRANSMIT PRE-EMPHASIS - A high-speed signaling system with adaptive transmit pre-emphasis. A transmit circuit has a plurality of output drivers to output a first signal onto a signal path. A receive circuit is coupled to receive the first signal via the signal path and configured to generate an indication of whether the first signal exceeds a threshold level. A first threshold control circuit is coupled to receive the indication from the receive circuit and configured to adjust the threshold level according to whether the first signal exceeds the threshold level. A drive strength control circuit is coupled to receive the indication from the receive circuit and configured to adjust a drive strength of at least one output driver of the plurality of output drivers according to whether the first signal exceeds the threshold level.
|EYE DIAGRAM SCAN CIRCUIT AND ASSOCIATED METHOD - Eye diagram scan circuit and associated method for a receiver circuit, including a level adjust circuit, a phase interpolator and a control module. The receiver circuit provides a first data signal and a primary phase data according to a received signal. The control module provides a phase offset data and a level offset data. The level adjust circuit adjusts a level of the received signal in respond to the level offset data; the phase interpolator triggers according to a sum of the phase offset data and the primary phase data, so a second data signal is provide in response to the level-adjusted received signal. The control module compares the first data signal and the second data signal, and accordingly provides an eye diagram scan result for the phase offset data and the level offset data.
|RECEIVER WITH DISTORTION COMPENSATION CIRCUIT - A receiver containing analog circuitry that generates distortion, a distortion compensation circuit coupled to an output of the analog circuitry, and a slicer, operating as a signal peak detector, coupled to the distortion compensation circuitry. The distortion compensation circuit has a subtractor, a function generator, and a weighting circuit. The subtractor has a first input coupled to the output of the analog circuitry, a second input, and an output. The function generator has an input coupled to the first input of the subtractor. The weighting circuit, responsive to a weighting coefficient, is coupled between an output of the function circuit and the second input of the first subtractor. The function generator has a transfer function with a third-power term and the weighting coefficient is set to a value based on the level of the signal peaks that will least partially reduce distortion in signals on the output of the subtractor.
|METHOD AND APPARATUS FOR CALIBRATING AN ENVELOPE TRACKING SYSTEM - A method of calibrating an envelope tracking system for a supply voltage for a power amplifier module within a radio frequency (RF) transmitter module. The method includes deriving a mapping function between an instantaneous envelope of a waveform signal to be amplified by the power amplifier module and the power amplifier module supply voltage to achieve a constant power amplifier module gain based on a gain compression factor, setting an envelope tracking path of the transmitter module into an envelope tracking mode in which mapping between the instantaneous envelope of the waveform signal and the power amplifier module supply voltage is performed using the derived mapping function, applying a training signal comprising an envelope that varies with time to the RF transmitter module, measuring a battery current, modifying the gain compression factor based on the measured battery current, and re-deriving the mapping function based on the modified gain compression factor.
|Upstream frequency response measurement and characterization - Upstream frequency response measurement and characterization. Signaling is provided between respective communication devices within a communication system. Based upon at least one of these signals, one of the communication devices captures a number of sample sets corresponding thereto at different respective frequencies (e.g., a different respective center frequencies, frequency bands, etc.). Then, spectral analysis is performed with respect to each of the sample sets to generate a respective and corresponding channel response estimate there from. After this number of channel response estimates is determined, they are combined or splice together to generate a full channel response estimate. In implementations including an equalizer, different respective sample sets may correspond to those that have undergone equalization processing and those that have not.
|METHOD FOR PASSING SIGNALS THROUGH A MEDIUM UNDER MONITORING - The method for passing signals through a medium under monitoring consists in generating a reference signal, transmitting this reference signal in a forward direction through the medium under monitoring by means of at least one transmitting electrical circuit, receiving the signal passing in the forward direction through the medium under monitoring by means of at least one receiving electrical circuit, transmitting the generated reference signal in the reverse direction through the medium under monitoring by means of the at least one receiving electrical circuit, receiving the signal passing in the reverse direction through the medium under monitoring by means of the at least one transmitting electrical circuit and thus ensuring the passage of signals through the medium under monitoring. The method for passing signals through a medium under monitoring ensures the production of signals passing through the medium under monitoring which have a high degree of identity.
|RECEIVER, SYSTEM INCLUDING THE SAME, AND CALIBRATION METHOD THEREOF - A receiver includes a fixed delay unit configured to delay a first clock signal received from a clock channel by a predetermined time and output a second clock signal; a first delay unit configured to delay the first clock signal in response to a first control signal; a first data sampler configured to sample a data signal received from a data channel in response to an output signal of the first delay unit and output a first data signal; a second delay unit configured to delay the first data signal in response to a second control signal and output a second data signal; a second data sampler configured to sample the second data signal in response to the second clock signal; and a delay controller configured to output the first control signal and the second control signal.
|ADAPTIVE MODULATION AND CODING SCHEME ADJUSTMENT IN WIRELESS NETWORKS - In a method of adjusting a modulation and coding scheme (MCS) level for a transmission on a communication channel between a base station and a mobile terminal, at the base station: a target value for an error metric is defined; the error metric is measured; an MCS offset based on a degree of deviation of the measurement of the error metric from the target value is determined; an indication of a channel quality measurement for the communication channel is received from the mobile terminal; a pre-adjusted MCS level corresponding to the indication of the channel quality measurement is determined using a fixed mapping between a set of channel quality levels and a corresponding set of MCS levels; an adjusted MCS level is determined by adding the MCS offset to the pre-adjusted MCS level; and the adjusted MCS level is assigned to the transmission.
|SYSTEMS AND METHODS FOR MULTIMODE SIGNAL ACQUISITION - Systems and methods for multimode signal acquisition. The systems include a multimode receiver that is configured to determine a communication mode for a received signal. The receiver includes, for example, one or more analysis modules for analyzing a characteristic of a portion of the received signal (e.g., a preamble). The receiver samples the received signals and one or more analysis modules perform frequency analysis on the digital form of the received signal (e.g., using a Goertzel algorithm). The outputs of the analysis modules are then provided to a classification module. The classification module compares, for example, a power spectral density ("PSD") value for one or more frequencies of interest specific to the different communication modes to predetermined PSD values at those frequencies to determine the communication mode. The receiver is then configured for the full acquisition of signals transmitted using the determined communication mode.
|SIGNAL GENERATION DEVICE, MOBILE COMMUNICATION TERMINAL TEST DEVICE INCLUDING THE SAME, SIGNAL GENERATION METHOD, AND MOBILE COMMUNICATION TERMINAL TEST METHOD - To provide a mobile communication terminal test device that can generate a signal with amplitude-frequency characteristics or phase-frequency characteristics which are changed over time. A mobile communication terminal test device
|ADJUSTABLE TRANSMITTER POWER FOR HIGH SPEED LINKS WITH CONSTANT BIT ERROR RATE - A method and apparatus for dynamically adjusting power of a transmitter is herein described. A transmitter transmits a pattern to a receiver at a differential voltage. The length of the pattern, in one embodiment, is selected to be a reasonable length training pattern, as not to incur an extremely long training phase. If errors are detected at the receiver in the pattern, the transmitter steps the differential voltage until errors are not detected in the pattern at the receiver. The differential voltage, where no errors are detected, is scaled by a proportion of a target confidence level to a measured confidence level associated with the reasonable length training pattern. As a result, a training phase is potentially reduced and power is saved while not sacrificing confidence levels in error rates in the data exchange between the transmitter and receiver.
|GSM/EDGE TRANSMIT POWER CALIBRATION AND CHARACTERIZED DIGITAL PREDISTORTION CALIBRATION USING MULTI-BAND MULTI-CHANNEL MULTI-CHAIN SWEEP - A method and apparatus for characterized pre-distortion calibration is provided. The method begins with the selection of a number of devices to be characterized. The number of devices selected may be a subset of a larger group of devices. The selected number of devices is then characterized. The method avoids characterizing the large group of devices. The apparatus includes a processor for performing pre-distortion calibration, a processor for averaging curves for each RF gain index on each channel, and a non-volatile memory.
|APPARATUS AND METHOD FOR ESTIMATING DOPPLER SPREAD IN MOBILE COMMUNICATION SYSTEM - An apparatus and a method for estimating a Doppler frequency in a mobile communication system are provided. The apparatus includes an estimator for temporarily estimating a maximum Doppler frequency based on channel values sampled according to a first period in a frame, a detector for calculating at least one correlation value between at least one channel value additionally sampled in the frame and at least one channel value sampled over the first period, and for determining whether aliasing occurs based on the correlation value, and a determiner for determining a final maximum Doppler frequency according to the occurrence or non-occurrence of the aliasing.
|TIME DELAY ESTIMATION - A method for time delay estimation performed by a physical computing system includes passing a first input signal obtained by a first sensor through a filter bank to form a first set of sub-band output signals, passing a second input signal obtained by a second sensor through the filter bank to form a second set of sub-band output signals, the second sensor placed a distance from the first sensor, computing cross-correlation data between the first set of sub-band output signals and the second set of sub-band output signals, and applying a time delay determination function to the cross-correlation to determine a time delay estimation.
|MODULATION ANALYSIS AND DISTORTION IDENTIFICATION - An apparatus, method, computer readable medium, and system are provided to generate a symbol placement associated with a transmission scheme by transforming a retrieved set of equalization coefficients. Symbols included in the symbol placement may be analyzed and quantified in terms of their distance from a decision boundary. Symbols may be synthesized on an iterative basis in order to obtain visibility into the underlying performance of the transmission scheme over time. If equalization is unable to reduce a signal impairment below a threshold value within a predetermined amount of time, then a determination may be made that a non-linear distortion source is present in a network or communication system. Signals received from a plurality of user terminals may be compared with one another in order to determine a probable location or cause of the non-linear distortion.
|Radio Frequency Multipath Channel Emulation System and Method - A multipath channel emulation system and method are disclosed. In some aspects, the system and method allow for analog emulation of a multipath MIMO wireless channel. Such multipath channel emulation system is used for testing the ability of wireless communication devices to operate in an airlink channel characterized by multipath. In a particular aspect, an impedance mismatch or discontinuity is provided in an open-ended coaxial cable so as to cause multiple back and forth reflections between an impedance discontinuity and an open coaxial cable stub and, optionally, including a delay element to emulate a multi-cluster multipath environment. A plurality of such stub subsystems may be combined as sub-paths in a multipath channel emulator.
|METHOD OF TIME-SYNCHRONIZED DATA TRANSMISSION IN INDUCTION TYPE POWER SUPPLY SYSTEM - The present invention provides a method of time-synchronized data transmission in induction type power supply system, comprising timers and programs installed in a supplying-end module and a receiving-end module to predict the time for generating the trigger signal at the receiving-end end and perform steps for detecting signals to avoid omission. Under the condition of high power transmission, power output on the supplying-end coil is pre-reduced prior to the time expected for receiving trigger data, making the main carrier wave amplitude decrease in a short time period. In every process of data transmission, timers are mutually calibrated and synchronized again to transmit power without detecting and receiving in the period when no data are expected to be transmitted, thus preventing interference of power load noise and enabling the induction type power supply system to transmit data code stably.
|Calibration Sub-System for Telecommunication Systems - A calibration sub-system for calibrating a unit of a distributed antenna system is provided. The calibration sub-system includes a signal generator, a receiver, and a processor. The signal generator provides test signals to a communication path that are generated based on modification schemes for an in-phase signal component ("I component") or a quadrature signal component ("Q component"). The receiver receives output signals generated from test signals. The processor determines output power values for an undesirable signal component of the output signals. Each output power value is a Taylor series function or a polynomial function of a respective modification scheme for the I or Q component of the respective test signal. The processor determines an optimal modification scheme for the I or Q component that minimizes an output power of the undesirable signal component. An output value of the function is minimized by having the optimal modification scheme as an input.
|COMMUNICATION SYSTEM WITH FEEDBACK MECHANISM AND METHOD OF OPERATION THEREOF - A method of operation of a communication system includes: determining a channel estimate based on an arriving communication for characterizing a channel; calculating a conditional measure based on the channel estimate for characterizing the channel at a subsequent index; generating a channel-based probability function using the conditional measure, the channel-based probability function based on a feedback metric; determining a stochastic channel indicator based on a value of the feedback metric producing a target condition from the channel-based probability function; and sending the stochastic channel indicator for controlling communication at a base station for communication through a device.
|Method and System for Frame Formats for MIMO Channel Measurement Exchange - A method and system for frame formats for MIMO channel measurement exchange is provided. Aspects of a method for communicating information in a communication system may comprise transmitting data via a plurality of radio frequency (RF) channels utilizing a plurality of transmitting antenna, receiving feedback information via at least one of a plurality of RF channels, and modifying a transmission mode based on the feedback information. Aspects of a method for communicating information in a communication system may also comprise receiving data via a plurality of receiving antenna, transmitting feedback information via at least one of the plurality of RF channels, and requesting modification of a transmission mode for the received data in transmitted response messages comprising the feedback information.
|AUTOMATIC GAIN CONTROL IN A RECEIVER - Automatic gain control in a receiver. A method for controlling operating range of an analog-to-digital converter (ADC) by an automatic gain control circuit includes estimating a peak-to-average ratio corresponding to an analog signal from digital samples of the analog signal. The method includes determining a peak value corresponding to the analog signal based on the peak-to-average ratio. Further, the method includes maintaining magnitude of the analog signal at an input of the ADC and gain of the receiver based on the peak value.
|COMMON MODE SIGNAL REDUCTION IN POWERLINE COMMUNICATION DEVICES - An active common mode current limiting mechanism limits common mode currents in a powerline communication device. A powerline coupler determines a common mode signal component of an output signal of the powerline communication device. The powerline coupler provides voltage estimates of the common mode signal component to a signal processing unit. The signal processing unit generates samples of the voltage estimates of the common mode signal component. The signal processing unit adjusts transmit voltage levels of the powerline communication device based on the samples of the voltage estimates of the common mode signal component to limit the common mode signal component of the output signal.
|Method and Apparatus for Measurement Report for the Decision of Transmission Mode Transition - Disclosed are a method and apparatus for measurement report for the decision of transmission mode transition that obtain a threshold value of reporting CQI_difference of all frequency sub-bands; measure a CQI value at each CQI reporting frequency sub-band of whole frequency band in each measure time interval; determine a CQI_difference value based on the measured CQI value of each CQI reporting frequency sub-band; and compare the determined CQI_difference value with the threshold value, if a condition is satisfied, then the UE sends the determined CQI_difference value to the BS. After the UE has reported this measurement report to the BS, the BS may choose a more suitable data transmission mode for the UE based on this measurement report to make data transmission more effective.
|Spectrally constrained impulse shortening filter for a discrete multi-tone receiver - A channel in a multiple carrier communication system is equalized by computing a target spectral response, shortening the impulse response of the channel so that a significant part of an energy of the impulse response is confined to a region that is shorter than a target length and filtering the signal based on the target spectral response.
|RECEIVING AN INPUT SIGNAL OVER A CHANNEL OF A WIRELESS NETWORK - Method, apparatus and computer program product for processing an input signal received over a channel of a wireless network at an apparatus. In one embodiment, an apparatus includes a plurality of receiver processing means, wherein each one of the plurality of receiver processing means is repeatedly selected to perform the processing of the input signal for a respective time interval thereby generating a respective plurality of output signals and, only one of the receiver processing means is selected for said processing at a time. A respective quality measure of each of the plurality of output signals is compared. The selection of the plurality of receiver processing means is controlled in dependence upon the comparison of the quality measures of the output signals, such that the receiver processing means which generates the output signal having the quality measure indicating the highest quality is selected for the longest time interval.
|BLIND I/Q MISMATCH COMPENSATION WITH RECEIVER NON-LINEARITY - Apparatus and methods disclosed herein perform gain, clipping, and phase compensation in the presence of I/Q mismatch in quadrature RF receivers. Gain and phase mismatch are exacerbated by differences in clipping between I & Q signals in low resolution ADCs. Signals in the stronger channel arm are clipped differentially more than weaker signals in the other channel arm. Embodiments herein perform clipping operations during iterations of gain mismatch calculations in order to balance clipping between the I and Q channel arms. Gain compensation coefficients are iteratively converged, clipping levels are established, and data flowing through the network is gain and clipping compensated. A compensation phase angle and phase compensation coefficients are then determined from gain and clipping compensated sample data. The resulting phase compensation coefficients are applied to the gain and clipping corrected receiver data to yield a gain, clipping, and phase compensated data stream.
|METHOD FOR DETECTING WITH A HIGH TEMPORAL ACCURACY A THRESHOLD CROSSING INSTANT BY A SIGNAL - A method detects a threshold crossing instant at which a signal crosses a threshold, by: sampling the signal at plural sampling instants spaced from one another by a sampling period; detecting consecutive first and second sampling instants at which the signal has a first signal value lower than or equal to the threshold, and the signal has a second signal value higher than the threshold, respectively; calculating a first interval indicative of a time between the threshold crossing instant and the first sampling instant; setting a reference signal having a reference amplitude representing the first interval relative to a reference scale; generating a signal with a delay depending on said reference signal; generating a threshold crossing detection signal at an instant delayed by a second interval; calibrating the reference scale of the reference amplitude so that the second interval is substantially equal to the first interval.
|RECEIVING DEVICE, SIGNAL PROCESSING DEVICE, AND SIGNAL PROCESSING METHOD - A receiving device according to the present invention includes: a receiver for receiving an OFDM symbol that is modulated by phase shift keying; an FFT processor for applying an FFT process to the received OFDM symbol to obtain a subcarrier signal; a demapping unit for demapping the subcarrier signal to generate a bit string; a norm calculator for calculating the norm of the subcarrier; a weighting factor generator for generating a weighting factor by taking the statistics of the calculated norm; and a weighting unit for obtaining a soft decision value by weighting the bit string after demapping, based on the particular weighting factor. Thus, the receiving device can obtain a soft decision value to achieve good decoding performance with a small number of known signals and processes.
|LINK ADAPTATION FOR MULTIMODE MIMO WIRELESS SYSTEM - A wireless receiver is disclosed that is capable of efficiently selecting a preferred transmission/detection scheme for use in wireless communication. The wireless receiver may be capable of communicating using any one of several transmission/detection schemes. Therefore, in order to select a preferred transmission/detection scheme, the wireless receiver calculates at least one metric for the transmission/detection schemes. In MIMO systems, the link adaptation is more complex and the metrics typically must be more accurate. Because of the potentially substantial amount of calculation that may be required to calculate the metric, the wireless receiver is capable of performing the individual calculations in optimized ways, as well as easily reducing the total number of metrics required to be calculated so as to reduce overall complexity.
|DIGITAL BROADCASTING RECEIVING SYSTEM AND ASSOCIATED SIGNAL PROCESSING METHOD - A digital broadcasting receiving system is provided. A receiving module receives an M number of symbols each carrying an N number of subcarriers of a control signal. A converting module performs FFT on respective k
|SYSTEMS AND METHODS FOR USING PROTOCOL INFORMATION TO TRIGGER WAVEFORM ANALYSIS - Systems and methods are disclosed herein to provide communication test systems for the testing of packet data communication devices, systems and networks. According to one aspect of the subject matter described herein, a test system containing an integrated traffic, protocol and waveform analyzer is disclosed that includes a traffic generator/analyzer and a protocol engine that triggers a waveform analyzer to analyze the signal waveform of a device under test at a predetermined point. Such a test system may offer improved capabilities such as a more selective and accurate measurement of complex signal waveforms, more automated measurements of waveforms pertaining to wireless communication data streams, and more rapid identification and measurement of waveforms corresponding to errored packets.
|Crosstalk Estimation Methods and Apparatus Using Auxiliary Time-Domain Signals - Techniques are disclosed for measuring crosstalk between at least two communication channels of a communication system. A receiver of the system receives a signal over a given one of the communication channels from a transmitter of the system. The receiver correlates the received signal with a sequence of time-domain signals associated with another of the communication channels, and generates a measure of crosstalk between the given communication channel and the other communication channel based on the correlation between the received signal and the sequence of time-domain signals. The sequence of time-domain signals may be selected from a designated set of M-sequences.
|Test Signal Generating Apparatus for Communications Equipment and Test Signal Generating Method for Communications Equipment - A test signal generating apparatus for communications equipment sequentially uses first and second sequence information which are stored in a sequence memory for storing the first sequence information including a reading order and read addresses of unit data including I and Q waveform data, and desired signal levels to be set to the unit data, and the second sequence information including frequency offsets. Consequently, the test signal generating apparatus provides frequency offsets at a plurality of steps every predetermined frequency intervals by using a predetermined carrier frequency as a reference, with respect to the I and Q waveform data at a digital stage up to digital-to-analog converters, and outputs a test signal in the frequency hopping system.
|BEAM-STEERING CONFIGURATIONS AND TESTS - An apparatus, method and system for beam-steering configurations and tests in a communication system. In one embodiment, the apparatus includes a processor
|RATE ADAPTATION ALGORITHM USING RAW BIT ERROR RATE - Rate adaptation in network communications can be determined, at least in part, by bit error rates through network communication channels. Bit error rates can provide an indication of channel conditions and can guide selection of data rate settings by network devices. Relatively good channel conditions can support relatively higher data rates while communication channels with relatively more noise and/or interference can support relatively lower data rates. Transmitted data can be coded with Forward Error Correction codes that can allow determination of bit error rates resulting from transmission. In one embodiment, bit error rates can guide carrier selection when data is transmitted with groups of two or more carriers such as with orthogonal frequency division multiplexing modulation.
|APPARATUS AND METHOD FOR SELF-TESTING A COMPONENT FOR SIGNAL RECOVERY - A circuit having a component for signal recovery, such as an adaptive equalizer, may be tested in order to ensure that the component operates properly. Unfortunately, external test equipment may be expensive and prone to being damaged. According to an aspect of the disclosure, there is provided a circuit including BIST (Built-in Self-Test) circuitry for testing a component for signal recovery with a stress signal that simulates an imperfect signal received over a communication channel. The circuit also has a detector for determining whether the component is operating properly with the stress signal. Thus, no external test equipment is needed for testing the component. In some implementations, the BIST circuitry includes a low-pass filter for filtering a transmit signal into the stress signal. Thus, the amount of circuitry involved in generating the stress signal can be reduced.
|SYSTEMS AND METHODS FOR MEASUREMENT OF ELECTRICAL CHANNEL LOSS - In accordance with embodiments of the present disclosure, a method for characterizing electrical characteristics of a communication channel between a transmitter of a first information handling resource and a receiver of a second information handling resource may include receiving a test signal at the receiver from the transmitter during an in-situ characterization mode of the second information handling resource, converting the test signal into a discrete-time digital signal representing the test signal, generating a discrete-time finite difference function comprising a first derivative of the discrete-time digital signal, transforming the discrete-time finite difference function into a frequency-domain transform of the discrete-time finite difference function.
|Determining Transmission Latency - According to one embodiment of the invention, a method for receiving in a signal processing subsystem a first signal comprising a predetermined pattern and a second signal comprising the predetermined pattern, and determining by the signal processing subsystem a transmission latency between the received first signal and the received second signal based on the predetermined pattern. According to another embodiment a system comprising a pattern insertion subsystem to insert a predetermined pattern into a first signal and a second signal, and a signal processing subsystem to (i) receive the inserted first signal and the inserted second signal, and (ii) determine a transmission latency between the received signals based on the predetermined pattern.
|Amplitude/Phase Delay Calibration for Envelope-Tracking Amplifier - A system and method for estimating a time delay introduced by an envelope tracking amplifier (ETA) of a transmitter. The ETA receives a first baseband signal that is generated by the transmitter and operates on the first baseband signal to produce an output signal. The receiver receives a second baseband signal in response to the transmitter's transmission of the output signal. The receiver generates a model signal that represents an estimate of the first baseband signal. The receiver computes a first time delay between the amplitude envelopes of the second baseband signal and the model signal. The receiver computes a second time delay between phase signals derived respectively from the second baseband signal and the model signal. The receiver estimates the time delay that is introduced by the ETA of the transmitter by subtracting the second time delay from the first time delay.
|METHOD AND SYSTEM OF PAYLOAD ENCODING AND MODULATION FOR CHANNEL QUALITY FEEDBACK - The present invention relates to a method, a computer readable medium, and a system of payload encoding and modulation and, more particularly, to a method, a computer readable medium, and a system of payload encoding and modulation for channel quality feedback. A method includes sending a Channel Quality Indicator (CQI) in a x-bit modulation scheme, and after sending the CQI, sending at least one CQI in a y-bit modulation scheme, the at least one CQI indicating one of an increment and a decrement of a previous CQI. The method further includes detecting a trigger event, and when the trigger event is detected, sending the CQI in the x-bit modulation scheme.
|CHECKING CIRCUIT OF SENDING CONTROL - The object of the invention is to checking the timing easily and in shorter time, and reduce the power consumption without any influence on other circuits functions. The solutions are as follows. By the "1" detecting counter, the "0" detecting counter, and the data validity judging circuit in the checking circuit of transmission control included in the DSRC baseband circuit of the transmission apparatus, it becomes the possible to judge the data validity of the transmission data TX_DI
|SYSTEM AND METHOD FOR TESTING A RADIO FREQUENCY MULTIPLE-INPUT MULTIPLE-OUTPUT DATA PACKET TRANSCEIVER WHILE FORCING FEWER DATA STREAMS - In accordance with the presently claimed invention, a system and method are provided for testing multiple-input, multiple-output wireless radiofrequency (RF) packet data signal transceivers while operating in such ways as to communicate their signals using various combinations or permutations of packet data streams without requiring termination or re-establishment of communication links following transitions from one combination or permutation of packet data streams to another.
|TRANSITION INTERVAL CODING FOR SERIAL COMMUNICATION - A one-wire transmission protocol utilizes transition interval coding in which a value of a transmitted symbol is determined by comparing an interval length between the voltage transition associated with the transmitted symbol and a prior voltage transition on the communication link, to a threshold transition interval provided to the receiving device during the transmission sequence that includes the transmitted symbol. If the interval length of the symbol is below the transition interval threshold, the symbol is determined to be a first value and if the interval length of the symbol is above the transition interval threshold, the symbol is determined to be a second value. The transition interval threshold is provided in a start sequence that includes at least two transitions. The threshold transition interval width is based on one or more transition intervals determined during the start sequence.
|Interface with Variable Data Rate - A device includes a transmitter coupled to a node, where the node is to couple to a wired link. The transmitter has a plurality of modes of operation including a calibration mode in which a range of communication data rates over the wired link is determined in accordance with a voltage margin corresponding to the wired link at a predetermined error rate. The range of communication data rates includes a maximum data rate, which can be a non-integer multiple of an initial data rate.
|FLEXIBLE TIMEBASE FOR EYE DIAGRAM - A flexible timebase for eye diagrams uses a stable free running oscillator as a sample clock for equivalent time sampling of an input serial digital signal and of a reference signal, such as a sine wave, derived from a subdivided recovered clock of the input serial digital signal. The reference signal samples are provided to a digital phase-locked loop that provides the flexible timebase to an eye pattern generator. The eye pattern generator accumulates the input serial digital signal samples at times corresponding to the reference signal samples to produce the eye diagram. A linear phase detector in the digital phase locked loop converts the reference signal samples to a complex signal using a Hilbert transform and then to a linear ramp of phase values using a CORDIC algorithm with arctangent lookup table. A subtractor is then used to subtract the digital phase-locked loop feedback from the linear ramp to provide the input to the loop filter.
|COMMUNICATION APPARATUS AND COMMUNICATION METHOD - A communication apparatus calculates a residual component by noting one of a given plurality of transmitted signals and by canceling a component corresponding to a candidate/candidates for the other/others of the plurality of transmitted signals from a signal corresponding to one of a plurality of received signals. The communication apparatus determines a candidate for the given transmitted signal by selecting a value closest to the residual component from among the values that the given transmitted signal can take, and obtains a plurality of candidate groups by changing that given transmitted signal, each candidate group being constructed as a collection of candidate sets each comprising a candidate for that given transmitted signal and a candidate/candidates for that other transmitted signal/signals. Then, the communication apparatus selects transmitted signal candidate sets that are common to the plurality of candidate groups and estimates the plurality of transmitted signals using the selected candidate sets.
|Upstream Adaptive Modulation in a Communications System - A system and method for providing upstream adaptive modulation. Burst parameters associated with a range of data interval usage codes (IUCs) are defined. Each of the data IUCs has a different modulation order and forward error correction (FEC). The SNR and codeword error rate for each satellite modem in the network are monitored. The data IUCs are dynamically assigned to different satellite modems within an upstream channel based on SNR and/or codeword error rate to enable each of the satellite modems in the upstream channel to achieve maximum bandwidth efficiency during upstream data transmissions. Bandwidth requests are received from the satellite modems and granted. The grant includes the assigned data IUC. The data bursts received in the upstream channel are each processed using the parameters from the assigned IUC for each of the satellite modems sending data in the upstream channel. When any of the satellite modems' SNR and/or codeword error rate changes, the data IUC for that satellite modem is changed accordingly.
|LOGICAL TRIGGERING IN THE FREQUENCY DOMAIN - A frequency mask trigger capable of triggering based on a logical combination of two or more areas of a frequency mask transforms a frame of digital data representing an input signal into a frequency spectrum having a plurality of frequency bins, with each frequency bin having a power amplitude value. A frequency mask is defined having a plurality of reference power levels, one reference power level being associated with each frequency bin. Two or more areas of the frequency mask are defined, with each mask area corresponding to one or more of the frequency bins. A violation status is determined for each mask area by comparing all of the power amplitude values within each mask area to the associated reference power level. If any of the power amplitude values within the mask area violates the associated reference power level, then the entire mask area is deemed to be violated. A trigger signal is generated when a logical combination of the violation statuses of the mask areas is satisfied.
|System and Method for Outer Loop Link Adaptation for a Wireless Communications System - A system and method for outer loop link adaptation for a wireless communications system are provided. A method for transmitting information includes receiving information to be transmitted, the information includes at least one codeword, encoding the at least one codeword, and transmitting the encoded at least one codeword. The encoding is based on a measurement of a channel being used to transmit the information and performance measurements for the channel.
|DATA SIGNAL IMPROVEMENT USING SIGNAL PEAK DETECTORS IN A RECEIVER - Methods and systems are described for improving a data at a receiver using one or more signal peak detectors. A signal is received having an initial signal level from the transmitter, the signal having a long bit and a short bit. The initial signal voltage of the signal is measured using a signal peak detector. A pre-emphasis value is determined using the signal voltage and is communicated to the transmitter, causing the transmitter to transmit the signal using an adjusted signal level. A second signal voltage of the initial signal is measured using a second signal peak detector, the second signal voltage being used to determine the pre-emphasis value. In another embodiment, a state machine having data relating to appropriate pre-emphasis is used in determining the pre-emphasis value. In another embodiment, one peak detector is used to measure the long bit and another peak detector is used to measure the short bit. In another embodiment, the signal does not have associated link training data.
|Intrinsically Safe DSL Circuit - An electrical installation comprising control and/or monitoring means connected to a field device by means of an electrical communications circuit, in which the communications circuit comprises a power supply, a communications device, the field device as a load thereof, and Intrinsic Safety means, in which the communications device is adapted to send and receive signals over the communications circuit to and from the field device, in which the field device is adapted to send and receive signals over the communications circuit to and from the communications device, in which the Intrinsic Safety means renders all or part of the communications circuit Intrinsically Safe, in which the field device is located in an Intrinsically Safe part of the communications circuit, characterised in which the communications circuit is adapted to carry DSL signals, and in which the communications device and the field device communicate with one another according to the DSL protocol.
|User Interface for Signal Integrity Network Analyzer - A signal integrity network analyzer is provided. The analyzer preferably includes a characterization module for characterizing a device under test, an acquisition module for acquiring a waveform, a de-embedding module for selectively embedding and de-embedding on or more system fixtures, and an analysis module for performing analysis on the acquired waveform, with one or more system features selectively embedded or de-embedded. A single user interface is provided and is adapted to control the characterization module, the acquisition module, the de-embedding module and the analysis module.
|RECEIVER APPARATUS, COMMUNICATION SYSTEM, RECEPTION METHOD AND COMMUNICATION METHOD - A receiver apparatus
|METHODS AND APPARATUS FOR PSEUDO ASYNCHRONOUS TESTING OF RECEIVE PATH IN SERIALIZER/DESERIALIZER DEVICES - Methods and apparatus are provided for pseudo asynchronous testing of receive paths in serializer/deserializer (SerDes) devices. A SerDes device is tested by applying a source of serial data to a receive path of the SerDes device during a test mode. The receive path substantially aligns to incoming data using a bit clock. A phase is adjusted during the test mode of the bit clock relative to the source of serial data to evaluate the SerDes device. The source of serial data may be, for example, a reference clock used by a phase locked loop to generate the bit clock. The phase of the bit clock can be directly controlled during the test mode, for example, by a test phase control signal, such as a plurality of interpolation codes that are applied to an interpolator that alters a phase of the bit clock.
|Receiving Apparatus, Transmitting Apparatus, Reception Method, And Transmission Method - A reception unit receives data from communication apparatuses. A transmission unit transmits data to the communication apparatuses. A control unit determines, in an adaptive way, which modulation and coding schemes to use to transmit and receive data. At a first stage, a modulation and coding scheme with a low transmission rate or a modulation and coding scheme that minimizes power requirements is selected from among a plurality of candidates therefor. At a second stage, the modulation and coding scheme of at least one of the communication apparatuses is changed to another scheme having a higher transmission rate, when it is impossible to allocate sufficient resources for the modulation and coding schemes selected at the first stage.
|MULTIPLE INPUT MULTIPLE OUTPUT AND BEAM-FORMING DATA TRANSMISSION METHOD AND DEVICE - The present invention provides a method and system for transmitting Multiple Input Multiple Output (MIMO) beam forming data. The method comprises: performing MIMO coding on data streams to obtain the coded data streams; obtaining weight values W=(W
|Time Delay Estimation - An amount of delay between a digital reference signal and a digital derived signal is measured, wherein the derived signal is derived from the reference signal. Measurement involves ascertaining a sign of a slope of the derived signal over a first time interval and producing a set of time-associated reference signs by ascertaining a sign of a slope of the reference signal over each of a plurality of different time intervals leading up to the first time interval. A first set of coincidence results is produced by detecting coincidence between the sign of the slope of the derived signal and each one of the time-associated reference signs in the set of time-associated reference signs. The first set of coincidence results is used alone or in combination with other coincidence results as an indicator of the amount of delay between the reference signal and the derived signal.
|METHOD AND APPRATUS FOR SPECTRUM SENSING FOR OFDM SYSTEMS EMPLOYING PILOT TONES - Methods and apparatuses for OFDM spectrum sensing are provided. The proposed spectrum sensing algorithms are based on Time-Domain Symbol Cross-Correlation (TDSC-MRC and TDSC-NP methods) and can be applied to all existing wireless OFDM systems. The statistical behaviors of the TDSC-based spectrum sensors are explicitly analyzed. In addition, the spectrum sensing method employing the Cyclic Prefix of the OFDM modulated signals (CP method) is described for comparison purposes. The DVB-T Standard is adopted as an application example to illustrate the proposed spectrum sensing algorithms. Simulation results show that the TDSC-MRC method outperforms the CP method for all values of CP ratio considered. The TDSC methods have the advantage that the detection performances are the same for different CP ratios, while the detection performance of the CP method degrades dramatically when the CP ratio becomes small.