text:
In an optical data transmission system, one channel is removed from a group of wavelength division multiplexed optical channels and another channel carrying different information at the same wavelength is inserted in its place. The process occurs by adding an optical signal whose electric field is the difference between the electric field of the new and old channels. The difference calculation takes into account the phase of the incoming WDM channel and phase of the laser source of the difference signal. The method has applications in optical transmission networks as add-drop nodes and optical regenerators, for generation of high bandwidth optical signals, and for secret optical communications.
1. An optical communications system receiving an input optical signal and producing an output optical signal, said optical communications system comprising:
a combining means for receiving the input optical signal and an add optical signal, said combining means combining the input optical signal and add optical signal such that the input optical signal and the add optical signal coherently interfere to form the output optical signal;
wherein the light source of the add optical signal is not the light source for the input optical signal, and the optical spectrum of the add optical signal has substantial magnitude at those frequencies where the optical spectrum of the input optical signal has substantial magnitude;
at least one laser;
at least one modulation subsystem;
at least one digital to analog (D/A) converter; and
a digital signal processor; and
the input optical signal contains at least one input wavelength division multiplexed channel, the output optical signal having at least one output wavelength division multiplexed channel; and
light from said lasers is modulated by said modulation subsystems;
said combining means combines the modulated light from said modulation subsystems with one another and with the input optical signal;
each of said modulation subsystems is adjusted by at least one analog voltage, said analog voltage being produced by one of said D/A converters;
said D/A converters are controlled by said digital signal processor; and
the optical phase of light from said lasers with respect to one another is known by said digital signal processor and the optical phase of said input wavelength division multiplexed channels compared to light from said lasers is known by said digital signal processor; and
the combining means sending the output optical signal;
whereby said output optical signal contains information.
2. The optical communication system of
at least one input monitor; and
at least one input monitor splitter; and
each of said input monitor splitters has directed to it light which at least partially corresponds to the input optical signal and each of said input monitor splitters separates a portion of power of the light directed to said input monitor splitter to form at least one replica of the light directed to said input monitor splitter;
said input monitors receive the replicas;
each of said input monitors includes sampled coherent detection means and delivers data to said digital signal processor; and
said digital signal processor knows the electric field envelopes of said input wavelength division multiplexed channels.
3. The optical communication system of
replicas of light from said laser are directed to a phase comparison unit comprising a phase comparison unit combiner, a photodetector and an (analog to digital) A/D converter; and
light from said lasers is combined by said phase comparison unit combiner and delivered to said photodetector, said photodetector is electrically connected to said A/D converter, and said A/D converter communicates with said digital signal processor;
whereby the optical phase of light from said lasers with respect to one another is known by said digital signal processor.
4. The optical communication system of
each of said output monitors receives light which at least partially corresponds to the output optical signal and each of said output monitors comprises sampled coherent detection means;
whereby said digital signal processor knows a basic parameter of said lasers compared to one another and compared to said input wavelength division multiplexed channels.
5. The optical communication system of
said output monitor receives an output monitor optical signal which is the output optical signal or a replica of the output optical signal;
said output monitor includes a sampled coherent detection means; and
said sampled coherent detection employs local oscillator light and said local oscillator light tunes in wavelength over a period of time;
whereby said digital signal processor knows a basic parameter of said lasers compared to one another and compared to said input wavelength division multiplexed channels.
6. An optical communications system comprising:
a plurality of lasers;
a plurality of modulation subsystems;
an optical combining means;
a plurality of digital to analog (D/A) converters; and
a digital signal processor; and
each of said plurality of lasers is modulated by one of said plurality of modulation subsystems;
each of said modulation subsystems is adjusted by at least one analog voltage,
said analog voltage being produced by one of said D/A converters;
said D/A converters are controlled by said digital signal processor;
the optical phase difference between light from said lasers is known by said digital signal processor and the states of polarization of light from said lasers with respect to one another is known by said digital signal processor; and
the optical combining means combines light from said modulation subsystems to form an output optical signal;
whereby the output optical signal occupies a contiguous region of optical spectrum wider than the optical spectrum occupied by any one of said modulated lasers, and the output optical signal contains information.
7. The optical communication system of
the phase comparison unit is in communication with the digital signal processor; and
the phase comparison unit receives light from the lasers, and calculates the phases of the lasers with respect to one another.
8. A method of producing an output optical signal from an input optical signal, said method comprising the step of:
coherently interfering said input optical signal with an add optical signal, the light source for the add optical signal being a different light source to the light source for the input optical signal, and the optical spectrum of the add optical signal having a substantially similar shape to the optical spectrum of the input optical signal;
whereby the output optical signal contains information;
wherein when the input optical signal contains at least one input wavelength division multiplexed channel and the output optical signal contains at least one output wavelength division multiplexed channel, further comprising the steps of:
modulating light from at least one laser by at least one modulation subsystem;
combining light from said modulated lasers to form the add optical signal; and
controlling said modulation subsystems by a digital signal processor, said digital signal processor knowing the optical phase of light from said lasers with respect to one another and knowing the optical phase of said input wavelength division multiplexed channels compared to light from said lasers.
9. The method of producing an output optical signal of
directing light from said lasers to a photodetector producing an electrical photodetector output signal;
digitizing said electrical photodetector output signal into photodetector output data; and
communicating said photodetector output data to said digital signal processor;
whereby said digital signal processor knows the optical phase of light from said lasers with respect to one another.
10. A method of producing an output optical signal comprising the steps of:
modulating a first laser having a first wavelength by a first modulation subsystem to produce a first add optical signal;
modulating a second laser having a second wavelength by a second modulation subsystem to produce a second add optical signal;
controlling said first and second modulation subsystems by a digital signal processor, said digital signal processor knowing the optical phase difference between light from said first and second lasers and the states of polarization of light from said first and second lasers with respect to one another; and
choosing the separation between said first wavelength and said second wavelength so that said output optical signal occupies a contiguous region of optical spectrum wider than the optical spectrum occupied by either of the first add optical signal or the second add optical signal;
whereby the output optical signal contains information.
11. The method of producing an output optical signal of
This application is a divisional application of a U.S. patent application (Ser. No. 11/377,783) entitled "COHERENT OPTICAL CHANNEL SUBSTITUTION" filed Mar. 16, 2006 by Michael G. Taylor now U.S. Pat. No. 7,742,701 which claims the benefit of U.S. Provisional Patent Application Ser. No. 60/662,607 by Michael G. Taylor, filed Mar. 16, 2005, and is hereby incorporated by reference.
1. Field of the Invention
This invention relates to optical data transmission over optical fibers. Specifically, and not by way of limitation, the present invention relates to optical data transmission utilizing coherent optical channel substitution.
2. Description of the Related Art
Information has been transmitted over optical fibers for some time. Details about this field are disclosed in "Optical Communication Systems," by J. Gowar (Prentice Hall, 2nd ed., 1993) and "Fiber-optic communication systems" by G. P. Agrawal (Wiley, 2nd ed., 1997), which are herein incorporated by reference. The information is usually in the form of binary digital signals, i.e. logical "1"s and "0"s, but fiber optics is also used to transport analog signals, such as cable TV signals. The present invention may be utilized with either digital or analog signals. However, for simplicity and exemplary purposes only, digital signals are discussed with the present invention. It should be understood by those skilled in the art that the present invention may also be used with analog signals. Every optical data transmission system has a transmitter, which emits light modulated with information into the fiber, and a receiver at the far end which detects the light and recovers the information. A long distance digital link may also use one or more digital regenerators at intermediate locations. A digital regenerator receives a noisy version of the optical signal, makes decisions as to what sequence of logical values ("1"s and "0"s) was transmitted, and then transmits a clean noise-free signal containing that information forward towards the destination.
As discussed, in Agrawal, an optical signal that is modulated has a broadened spectrum occupying a range of frequencies. Consider propagation of Gaussian input pulses in optical fibers having the amplitude
As described herein, if an optical signal is said to carry information then that information is useful to a recipient of the optical signal. However, there are other disclosures which employ a broader definition, where any optical signal that varies with time is said to carry information. The broader definition does not apply in the explanation of the present invention. The variations of the optical signal with time must convey a message that is of value to a recipient in order for the optical signal to contain information.
In the 1990's optical amplifiers were deployed in telephony and cable TV networks, in particular erbium doped fiber amplifiers (EDFAs) were deployed. These devices amplify the optical signals passing through them, and overcome the loss of the fiber without the need to detect and retransmit the signals. A typical long distance fiber optic digital link might contain some digital regenerators between the information source and destination, with several EDFAs in between each pair of digital regenerators.
A. WDM Network Topologies and Add-Drop
Also in the 1990's, wavelength division multiplexing (WDM) was commercially deployed, which increased the information carrying capacity of the fiber by transmitting several different wavelengths in parallel.
There are several different topologies that may be employed in a WDM fiber optic network, which are illustrated in
Most fiber optic transmission systems installed today have static add-drop configurations. There has been substantial research into all-optical networks where connections between nodes are set up and taken down in an automated fashion according to demand. All-optical networks are described in "A Precompetitive Consortium on Wide-Band All-Optical Networks," by S. B. Alexander et al. (IEEE J. Lightwave Technol., vol. 11, no. 5/6, p. 714-735, 1993) which is incorporated herein by reference. The add-drop technology must be able to switch multiple wavelength channels from add-drop to passthrough. Also the components involved in signal transmission, that is transmitters and receivers, fiber spans, optical amplifiers, etc., must be able to support a wide range of possible end-to-end link scenarios, as the connections in an all-optical network are changed according to customer demand. Using the add-drop technology to switch in a digital regenerator at intervals along the link helps support long transmission distance scenarios. Hence, there is a need for a flexible add-drop technology that may be switched in and out at any one wavelength and which may be operated at a range of wavelengths. Also there is a need for a digital regenerator which may be switched in and out of a link and which may be operated at a range of wavelengths.
B. Direct Detection & Coherent Detection
The transmitter unit for a single WDM channel contains a light source, usually a single longitudinal mode semiconductor laser. Information is imposed on the light by direct modulation of the laser current, or by external modulation, that is by applying a voltage to a modulator component that follows the laser. The receiver employs a photodetector, which converts light into an electric current. There are two ways of detecting the light: direct detection and coherent detection. All the installed transmission systems today use direct detection. Although it is more complex, coherent detection has some advantages, and it was heavily researched into in the 1980s and the start of the 1990s, and has become of interest once again in the past few years.
Most deployed transmission systems impose information on the amplitude (or intensity, or power) of the signal. The light is switched on to transmit a "1" and off to transmit a "0". In the case of direct detection, the photodetector is presented with the on-off modulated light, and consequently the current flowing through it is a replica of the optical power. After amplification the electrical signal is passed to a decision circuit, which compares it to a reference value. The decision circuit outputs an unambiguous "1" or "0".
There is another class of modulation formats where information is encoded on the phase of the optical signal, such as optical differential phase shift keying (oDPSK). A photodetector does not respond to changes in the phase of the light falling on it, so a passive component called a discriminator is used before the photodetector receives the optical signal. The discriminator converts the changes in phase into changes in power to which the photodetector can respond.
Since a photodetector does not respond to the phase portion of an optical wave, if two wavelengths are input to the photodetector, the photodetector does not distinguish between them. The photocurrent is proportional to the sum of the powers of the two wavelength channels. WDM systems work by using passive optical filter components to separate out the different wavelength channels at the receive terminal, so each photodetector sees only one channel. This approach puts a limit on how close the channels can be spaced, which comes from the optical filter's ability to pass one channel and reject its neighbours.
The coherent detection method treats the optical wave more like radio, inherently selecting one wavelength and responding to its amplitude and phase. "Fiber-optic communication systems" by G. P. Agrawal provides an introduction to coherent detection. Coherent detection involves mixing the incoming optical signal with light from a local oscillator (LO) laser source.
Following is a mathematical description of the coherent detection process. (The complex notation for sinusoids is summarised in the Appendix.) The electric field of the signal may be written as
There are two modes of coherent detection: homodyne and heterodyne. In the case of homodyne detection the frequency difference between signal and local oscillator is zero, and the local oscillator laser has to be phase locked to the incoming signal in order to achieve this. For homodyne detection the term ei(ω
With heterodyne detection there is a finite difference in optical frequency between the signal and local oscillator. All the amplitude and phase information on the signal appears on a carrier at angular frequency (ωs−ωLO), the intermediate frequency, and it can be detected with a demodulator using standard radio detection methods, such as synchronous detection, envelope detection or differential detection. Typically homodyne detection gives better performance than heterodyne detection, but is harder to implement because of the need for phase locking.
C. Sampled Coherent Detection
A new method of coherent detection called sampled coherent detection has been proposed and demonstrated recently, as described in U.S. Patent Application No. 2004/0114939 and in "Coherent detection method using DSP for demodulation of signal and subsequent equalization of propagation impairments" by M. G. Taylor (IEEE Phot. Tech. Lett., vol. 16, no. 2, p. 674-676, 2004) which are herein incorporated by reference. Digital signal processing (DSP) is employed in this method to obtain the information carried by a signal from the beat products seen at the outputs of a phase diverse hybrid. The field of digital signal processing is summarized below.
In sampled coherent detection, the signal and local oscillator are combined in a passive component called a phase and polarisation diverse hybrid.
The following mathematical treatment explains how the electric field of the signal is obtained from the outputs of the phase and polarisation diverse hybrid. The incoming signal electric field can be written as
Transmission over a length of optical fiber transforms the state of polarization of an optical signal, so that the digital values taken on by Es (t) as seen at the receive end of a fiber optic transmission system are typically not the same as those imposed at the transmit end. The polarization transformation can be reversed within the DSP by applying the appropriate rotation Jones matrix. The correct rotation matrix can be found by exploring the available space and then locking on to the matrix which gives the best quality signal. The polarization transformation of the optical fiber typically changes slowly, so the rotation matrix must be allowed to update.
The Jones vector Es (t) constitutes a complete description of the optical signal, or more precisely of the signal's optical spectrum in the region of the local oscillator. This means that any parameter of the optical signal can be deduced from Es (t). Employing sampled coherent detection is more complex than direct detection, but has many benefits. Phase encoded modulation formats can be employed, such as BPSK and quadrature phase shift keying (QPSK), which offer better sensitivity than on-off modulation formats. Also polarization multiplexed formats can be employed, which offer twice the information capacity for a given bandwidth of electro-optic components and a given optical spectral bandwidth. The polarization demultiplexing operation is performed within the digital signal processor, so no additional optical components are needed for it. In a long fiber optic transmission system carrying high bit rate signals the optical fiber propagation effects, such as chromatic dispersion and polarization mode dispersion, distort the signals. With sampled coherent detection the propagation effects can be reversed within the DSP by applying an appropriate mathematical operation.
Finally, a key benefit of sampled coherent detection is that it is equivalent to passing the signal through a narrow optical filter centered on the local oscillator wavelength, so no narrow optical filter components are needed for WDM. The LO can be tuned in wavelength, which is equivalent to tuning the optical filter, and lower WDM channel spacings should be possible with sampled coherent detection than with any WDM implementation using passive optical filters. However, because sampled coherent detection is a means of observing a signal, the narrow channel spacing is not available in conjunction with a WDM channel add-drop. At the add-drop node the dropped channel must be extinguished before the add channel is inserted, and even if the narrowest available physical optical filter were used, it would work correctly only if the neighboring channels were spaced farther away than if the only constraint were the ability to detect with sampled coherent detection. Hence it is desirable to have a method of dropping and adding a WDM channel which allows the same low channel spacing as with detection only.
D. Digital Signal Processing
The present invention utilizes digital signal processing (DSP). DSP is described in "Understanding Digital Signal Processing" by R. G. Lyons (Prentice Hall, 1996), herein incorporated by reference. A signal processor is a unit which takes in a signal, typically a voltage vs. time, and performs a predictable transformation on it, which can be described by a mathematical function.
Digital signal processing can be a better solution than analog signal processing for a task because the signal processing operation can be varied under programmable control and because operations can be performed that would require too much complexity if done by ASP. The examples presented herein refer to a single digital signal processor, but in fact the DSP may be made up of several processors that communicate with one another, and they do not have to be co-located.
E. Secret Communications
Additionally, there are applications for secret communications, where the information being transmitted is not available to someone who has access to the transmission system at an intermediate location. Optical transmission is not inherently secure. An eavesdropper who taps off some of the optical signal power may observe the same signal as the intended recipient. If the signal is a digital signal the eavesdropper can reconstruct the same digital sequence as the intended recipient. Using a phase or polarization encoded format will stop the eavesdropper receiving the information if direct detection is utilized, but not if coherent detection also is used.
Many encryption methods are available that operate on the digital data, as discussed in "Applied cryptography" by B. Schreier (Wiley, 2nd ed., 1996). Clearly, one of these encryption methods could be used prior to optical transmission and the corresponding decryption method after detection, to make the optical transmission link secure. Most encryption methods employ a secret key known to the intended recipient, but not to an eavesdropper. The key is a piece of data typically shorter than the message it encodes. The security of the code is maintained even if the eavesdropper knows the design of the code, provided he does not know the key being used by that particular recipient. If the length of the key is m bits, then the eavesdropper can break the code by trying all 2m possible values of key. m is chosen as a large value such that an exhaustive key search would require an unreasonable amount of time and effort. However, for many codes whose design has been published a mode of decrypting the code has been found, often after years of research, which requires less effort than trying 2m key combinations. Thus it is desirable to find new encrypting methods which inherently require an unfeasibly long time and/or large resources to break.
Transmission in the optical domain offers some features which allow encryption with a higher level of security than using the data domain. For example, the optical domain has a much higher information carrying capacity than an electrical cable or link. Frequency hopping (FH) is a method that has been used for some time in secure radio transmission, and can be applied to the optical domain as described in "Secure optical communications utilizing PSK modulation, polarization multiplexing and coherent homodyne detection with wavelength and polarization agility," by A. Salamon et al. (Military Communications Conference 2003 (MILCOM 2003), vol. 1, p. 274-282, 2003). The optical carrier frequency ωs is changed suddenly over time according to a frequency hop plan derived from the secret key. The intended recipient who knows the frequency hop plan can tune his receiver to the correct channel ωs (t) as it changes with time, and recover the signal that was sent. An eavesdropper must listen to all possible channels to be able to assemble the signal correctly. Security is improved by frequency hopping, but it can be defeated by an eavesdropper who has equipment to listen to all channels.
Thus, there is a need for an optical domain encryption method which can be implemented cost effectively for the intended information recipient but which is unfeasible to overcome by an eavesdropper.
The invention disclosed here is a method and apparatus to remove a WDM channel from an optical fiber and replace it with another channel of the same wavelength carrying different information. The substitution of the WDM channel is achieved by combining with the light passing through the optical fiber a modulated beam of light whose electric field can be considered to be the sum of two components. The first component cancels the WDM channel that is to be removed by destructive interference. The second component corresponds to the new WDM channel containing the new different information. The modulation on the beam of light that is added takes into account the optical phase of the WDM channel to be removed compared to the phase of the laser source from which the beam is obtained. Also, the modulation on the light beam takes into account the relative states of polarization of the WDM channel to be removed and the add laser source.
In one aspect, the present invention performs an add-drop function in an fiber optic telecommunications network.
In another aspect, the invention acts as a digital regenerator which replaces a noisy WDM channel with a channel at the same wavelength that has no noise. The density of WDM channels may be so high that demultiplexing using passive optical components is not possible.
In another aspect, the invention is a method to synthesize a WDM channel that occupies a wide optical bandwidth, such as a high baud rate digital signal, using several lasers at neighboring wavelengths. Each laser is modulated at a slower rate than would be required to generate the high baud rate optical signal directly.
In yet another aspect, the invention provides a way to phase lock one laser to an incoming optical signal without using feedback.
In a further aspect, the present invention is a secret communication system. Information which is intended to be secret is inserted into the spectrum of a broadband optical noise source, in such a way that an eavesdropper cannot identify the true information-bearing channel apart from a slice of noise spectrum. The information may be coded before being modulated onto an optical carrier in such a way that the optical signal resembles a spectral slice of optical noise. Only the intended recipient, who knows the spectral location of the channel and the coding method used to disguise the channel, can obtain the information on the channel without unreasonable time and effort.
The feature that is central to the configuration of
The process of changing the input optical signal into the output signal is described mathematically as follows. The input optical fiber contains a signal with electric field Re└Ein (t) eiω
To implement equation 3, the DSP in
In this disclosure, when it is stated that "the DSP knows" a parameter or that the parameter "is known by the DSP" then this signifies that the DSP may be programmed to calculate the parameter from the data it receives from A/D converters and from other data passed to it. It is not necessary for the DSP to actually calculate the parameter or have it stored in one of its registers for the DSP to know the parameter. For example, it might be stated below that parameter B can be calculated given that parameter A is known by the DSP. The designer of the DSP being skilled in the art will then understand how to program the DSP to calculate parameter B. However, the designer may choose an algorithm which starts from the values passed to the DSP from the A/D converters but does not calculate parameter A as an interim value, if such an algorithm uses fewer steps than one which does explicitly calculate parameter A.
The configuration of
Many variations of the configuration shown in
The amplitude modulators of
The configuration of
U.S. Patent Application No. 2004/0067064, U.S. Patent Application No. 2004/0105682 and U.S. Patent Application No. 2005/0007642 disclose optical transmitters where a laser is modulated by a modulation subsystem whose analog drive voltages are set by a digital signal processor via D/A converters. The modulation subsystems in these disclosures are capable of setting the inphase and quadrature parts of both states of polarization of the electric field envelope. These prior art disclosures are different from the present invention in that in the prior art disclosures the electric field envelope is chosen to precompensate for a fiber propagation impairment, whereas in the present invention the electric field envelope of the add signal is chosen to produce the desired output signal electric field envelope when the add signal is combined with the input signal.
A. Monitoring of Input and Output Signals
As discussed above, the description of coherent channel substitution does not cover how the input signal electric field is known to the DSP.
If the coherent signal substitution arrangement is being used as part of an add-drop node, then the input monitor can also be the detector that receives the drop channel.
A data connection 710 is shown in
There is a delay element 704 between the tap to the input monitor (point C) and the add coupler (A), and a delay element 706 between the add laser (B) and the add modulator subsystem (E). These optical delays may be implemented via optical fiber delay lines or delay lines in a planar waveguide platform. The first delay is present because the transit time from C to A has to match the processing delay, and realistically it takes time for the DSP to compute Ein (t) eiω
There is a delay between the add laser and the modulator in order to ensure that the phase of the add laser at a certain symbol in the input signal, as included in the measurement made by the input monitor, has not drifted when modulation is applied by the add laser modulation subsystem at that symbol. The requirement on the delays is
If the optical delay between the input monitor and the add coupler is exactly known, if the optical connections in
By applying monitoring and add laser modulation that implements equation 3 exactly, the output signal is the desired signal Re└Eout (t) eiω
U.S. Patent Application No. 2005/0008369 discloses equipment for an add-drop node where the drop signal is observed by coherent detection and where light from the same laser that is modulated to make the add channel is used as the local oscillator for the coherent detection of the drop channel. This disclosure is substantially different from the present invention in that in the aforementioned patent application the drop channel is removed from the main fiber by a passive optical filter, while in the present invention the drop channel is removed by optical interference with the add channel.
B. Arrangements to Work with Simple Modulation Formats
The equipment depicted in
An example is the case where the input and output signals are on-off modulated single-polarization signals. Assuming no additive noise or distortion, the electric field takes on values of either Eon{circumflex over (p)} (on state) or 0 (off state), where Eon is a scalar constant and {circumflex over (p)} is the Jones unit vector of the signal's SOP. Provided that the phase and SOP of the add laser are made to align with the input signal, the add signal electric field envelope needs to take on only three possible values: −Eon, 0 or Eon. A Mach-Zehnder modulator driven at −Vπ, 0 and Vπ may provide this modulation. The required modulation of the add laser in this case may thus be applied by the apparatus shown in
When the modulation format of the input and output optical signals is single polarization BPSK, then the add signal electric field envelope needs to take on only two values, −Eon or Eon. The arrangement of
In a typical add-drop situation the incoming signal contains additive noise. The best solution with respect to optical transmission quality is to have a high resolution D/A converter driving the Mach-Zehnder modulator, and to set the D/A converter so as to cancel the incoming (drop) signal+noise, as well as insert the outgoing signal. The output signal then contains minimal noise in its inphase component. However, it may be preferable to use a low resolution D/A converter, perhaps because such a component costs less or is available with higher bandwidth. The lowest resolution D/A converter that can be used has the same number of states as the add signal, that is three states in the example of on-off modulated input and output signals, or two states in the example of BPSK modulated input and output signals. The add-drop function is successfully performed when the lowest allowable resolution D/A converter is used, but the additive noise on the input signal is transferred to the output signal. The transmission system design must then take into account that noise accumulates over the whole length of the link.
The apparatus of
C. Multiple Channel Architecture
In the examples of coherent channel substitution described above, for every one WDM channel at the input, one add laser is used to make a single WDM channel at the output. If the monitor and modulation electro-optics have sufficient bandwidth, then several neighboring WDM channels at the input may be modified into several output channels by modulating a single add laser. In fact, the concept may be broadened so that Nin neighboring input WDM channels are substituted by Nout neighboring output WDM channels, by adding Nadd appropriately modulated add lasers; and where Nin, Nout and Nadd are not the same number. Each modulated add laser occupies a certain bandwidth of optical spectrum. The combination of all the modulated add lasers must occupy a contiguous region of spectrum that covers all the Nin input channels and all the Nout output channels.
Using a notation where the input WDM channel parameters are labeled with a subscript, so kth channel has electric field Re└Ein,k (t) eiω
The apparatus of
The function of the output monitor is to feed back values of parameters in the modulation subsystems, as in the single wavelength case. Preferably, the output monitor 1108 comprises a number of sampled coherent detection units whose local oscillators may be provided by the add lasers like the input monitor. In an alternative embodiment, the output monitor is a single sampled coherent detection unit and has one local oscillator which tunes in wavelength. By moving the LO between wavelengths so as to cover the whole of the relevant optical bandwidth, information may be obtained about the deviation of each of the add lasers in optical phase or SOP from the value assumed by the DSP. The LO must rove sufficiently quickly to avoid a substantial drift in optical phase or in SOP from any one add laser.
To calculate the Nadd different Madd,k (t){circumflex over (p)}add,k functions, the spectrum of the composite input and desired output electric field is divided into sections. A one-sided stitching function Gos (ω) is chosen which has the property that
The spectrum required of an add laser, the Kth add laser for example, after modulation is given by multiplying the Fourier transform of the required electric field difference on the right hand side of equation 6 by the appropriate stitching function GK (ω) (which is one of Gl (ω), Gm (ω) or Gh (ω) depending on whether K is a low, middle or high frequency channel). This operation is equivalent to the operation in the time domain of convolving the required electric field difference with the stitching function's impulse response gK (t), the inverse Fourier transform of GK (ω). The required modulated output of the Kth add laser is therefore
There are several configurations in a fiber optic transmission network where coherent channel substitution may be employed. Some of these configurations are listed below.
1. WDM Add-Drop
In this case one WDM channel is dropped at a node and another channel of the same wavelength is added. Multiple channels may be added or dropped. The main add-drop functions, that is the input monitor and add channel modulation of
The output signal may be a different modulation format or symbol rate from the incoming signal. The bandwidth of the D/A converters and electro-optics in the add laser modulation subsystem must be wide enough to cope with the higher of the symbol rates of the input signal and output signal. If the channel to be added has a higher symbol rate than the channel dropped, then there must be sufficient spectral bandwidth between any neighboring channels to accommodate the new higher bandwidth channel.
2. WDM Drop Only
In some applications of a drop node, as drawn in
The extinction of the drop channel may be achieved with the coherent channel substitution arrangement by setting
3. Digital Regenerator
The purpose of digital regenerator is to receive a digital signal after it has experienced additive noise and/or distortion, to make a decision which digital symbol value was sent for each symbol slot, and then transmit a sequence of clean symbol values free of noise and distortion. If the digital signal is encoded by a forward error correction (FEC) code, then the regenerator can decode the FEC to get a better estimate of the true symbol values, and subsequently transmit those values in FEC encoded form. In addition, a digital regenerator may modify overhead bits, for example to record the number of bit errors it has counted.
The digital regenerator function for a WDM channel may be implemented as a variation of the WDM add-drop case, where the information to be added is the same as the information dropped.
The coherent channel substitution process may implement a useful compensation feature for fiber propagation effects beyond what may be done by a conventional digital regenerator. With some fiber optic transmission systems the fiber propagation effects are managed, for example using chromatic dispersion compensation, such that the signal appearing at the receive end is sufficiently undistorted to detect it with low bit error rate (BER). However, the signal may be strongly distorted if observed at intermediate locations. This signifies that the fiber propagation management scheme may have to be modified to insert a regenerator at an intermediate point. With the coherent channel substitution regenerator the appropriate compensation for the accumulated propagation effects from the transmitter to the regenerator site may be applied after detection within the DSP. Then another transform may be applied before calculating the D/A converter values, so that the signal that leaves the regenerator is predistorted to take into account the path from the regenerator site to the receiver, but is in other respects a regenerated signal. The signal that arrives at the receive end of the link thus shows minimal distortion.
4. Tributary Add-Drop
A high bit rate signal is typically composed of many tributaries. These may be organized within the signal as packets, that is contiguous blocks of bits; by time interleaving of bits or bytes; or as part of a complex multiplexing structure, such as plesiochronous digital hierarchy. It may be required to perform an add-drop operation on some tributaries of a WDM signal, and leave other tributaries to continue. This operation may be performed by extracting the drop tributary information from the drop channel detector, and calculating Eout (t) so that it contains the required through tributaries and add tributaries.
5. Optical Phase Lock
There are applications where one laser, the slave, is to be made to have an optical frequency and optical phase that follows another laser, the master. Usually this is done via an optical phase locked loop. An OPLL was described above, as a component of an alternative configuration to achieve coherent channel substitution. It was noted that an OPLL is difficult to implement. It comprises a feedback loop which must have a short delay time and wide bandwidth. This forces the use of expensive components, and may prohibit using DSP technologies.
The coherent channel substitution method, excluding the option described above using an OPLL, provides an alternative way to achieve optical phase lock. The apparatus to achieve phase lock is illustrated in
U.S. Pat. No. 6,810,048 discloses an apparatus to achieve optical phase lock where a sideband to the slave laser optical frequency is generated by a single sideband modulator, and the frequency offset and phase of the sideband is controlled to be phase locked to the input signal master. This patent does not explain how the sideband frequency and phase are controlled to be phase locked to the master, but discloses that the sideband offset frequency is generated by a microwave oscillator. It is apparent from this patent that the sideband offset frequency must be a certain minimum value, since an electrical 90� hybrid driven at the offset frequency is used within the single sideband modulator, and such a component is not available that operates down to 0 Hz offset. In the aspect of the present invention where it is used to generate a phase locked optical slave signal, the endless phase adjustment 1507 is not driven by an oscillator. Instead it is driven by one or more analog voltages that are calculated by the DSP based on the phase difference between the laser 1504 and the input signal. To understand that these analog voltages cannot be considered to have come from an oscillator, the case where the phase difference between the laser and the input signal does not change over a period of time is considered. In that case the analog voltages driving the endless phase adjustment is constant over that period of time in consequence. U.S. Patent Application No. 2004/0208643 also discloses a way to phase lock the sideband of an optical carrier to a master input signal. In that disclosure a feedback loop configuration is used, which is similar to the standard method of achieving optical phase lock and is distinct from the present invention, which does not use feedback.
6. High Bandwidth Waveform Generation
To generate an optical signal modulated with a rapidly varying envelope normally requires a high bandwidth optical modulator. Coherent channel substitution offers an alternative way, by modulating several carriers with different parts of the required total optical spectrum, and then combining them. Each carrier requires a correspondingly lower bandwidth modulation subsystem. If the desired output signal envelope is Eout (t), then the multiple channel architecture of coherent channel substitution is implemented per equation 6 with
The configuration of
This approach allows an arbitrary signal envelope to be generated. The carrier still contains phase noise, which may be set to be equal to the phase noise of any one of the add lasers. Alternatively, if the phases and frequencies of the add lasers are known compared to one of the lines in a frequency-stabilized octave-spanning optical comb, then the waveform that is synthesized may be made to have an exact centre frequency compared to the reference radio frequency without phase noise. The optical carrier is then locked to the envelope. The phases of the add lasers may be found by beating at least one of them with the octave-spanning comb in a sampled coherent detection operation, or by using lines filtered from the comb in place of the add lasers.
E. Optical Domain Encryption
The secret optical communications aspect of the present invention is implemented by using the apparatus of
In a preferred embodiment of the present invention, the broadband optical noise source is implemented by an optical gain medium without feedback (i.e., an optical amplifier with a terminated input). Alternative optical noise sources may be used, for example based on supercontinuum generation. Any source of apparently random electric field over a broad optical spectrum may be used as the optical noise source. The DSP executes the coherent channel substitution via equation 3 where the electric field envelope Eout (t) is set to equal the desired envelope to carry the data (modified by the noise-rendering function described below). ωin and ωadd are time varying quantities according to the frequency hop sequence.
At the end of a frequency hopping interval, the add laser must be tuned rapidly to the next optical frequency in the predetermined frequency hop sequence. If the add laser is not capable of such rapid tuning then two (or more) lasers may be configured in parallel, and one of these lasers may be selected by a fast optical switch. The unused laser is tuned during the interval between frequency hop events, while the laser in use maintains its optical frequency.
The optical transmission system must support transmission of the broadband noise spectrum as though it contains information-bearing channels. If the optical signal-to-noise ratio of the link is not high enough, the optical noise can be filtered to a narrower optical spectrum, and the resulting reduction in the broadband noise optical bandwidth reduces the level of security to some extent. The detection method must be able to effectively select a WDM channel from its neighbors with no guard band, which is possible, for example, by using crosstalk subtraction in the DSP, as described in U.S. Patent Application No. 2004/0114939, or by orthogonal frequency division multiplexing.
1. Security Level of Optical Domain Encryption
The degree of security of the transmitted message using the method of the present invention may be estimated and compared to other optical domain encryption methods. First, the security level of frequency hopping alone is considered, in a configuration where one channel is transmitted. There is an improvement in security because the eavesdropper is forced to deploy Nch times as much receiving equipment as the intended recipient, where Nch is the number of possible frequency hop channels. It is easiest to design the system where the average time spent at each frequency is more than a digital symbol length (slow frequency hopping), but it may be less than a symbol length (fast frequency hopping).
Second, the case is considered where a number Ndum dummy channels carrying fake information are transmitted in addition to the one information-bearing channel (or equivalently other different information-bearing channels are added if there is need for them). This second scheme is more secure than the first scheme with only one channel. If the time spent at each frequency is τh (which does not have to be constant), the symbol length is τs and the number of bits/symbol is Ms. The data on the information-bearing channel should have the property that Mav consecutive bits must be received correctly to be able to reconstruct any of the message. This property may be imposed by applying a code to the data which has a long avalanche length. In order for a receiver to be able to recover any information Mav/Ms consecutive symbols or Mcor consecutive FH intervals must be received correctly, where
There is another aspect of the optical domain encryption scheme that makes it secure. The amount of information that the eavesdropper has to store to attempt to crack the code is very large. The C-band of an erbium noise source has several terahertz of bandwidth which must be sampled at the Nyquist rate equal to twice that bandwidth. The resolution of the A/D converters has to be high even if the modulation format is a binary format. The rate at which the eavesdropper processes information is the product of the sampling rate and the A/D converter resolution. While there are integrated circuits (ICs) available which process data at high line rates, for example for forward error correction processing, these ICs make a modest number of calculations on the input and then pass it on to the devices that follow. The processing that the eavesdropper must apply to the received data is to first attempt symbol phase, polarization and optical phase recovery; then try a very large number of permutations of different frequency hop intervals; and then crack the codes on the underlying data. This task is too much to be done within one IC and would occupy years (or more probably billions of years) duration using currently available IC technologies. In consequence, the raw data must be written to a slower storage medium and reside there until processing is complete. Thus, the eavesdropper must possess a very large amount of storage (in addition to the computing resources) to be able to record the encrypted signal, and this amount of storage can be made to be unfeasibly high. This feature gives the optical domain encryption method an additional degree of security over existing encryption methods, in that an eavesdropper cannot realistically even make a recording of the message to decrypt later.
An approach which can be taken by an eavesdropper to attack the encryption method is to apply processing on all of the channel slots to quickly decide which channel slots are not carrying an information-bearing signal, and discard any such channels. To successfully eavesdrop, a test is needed which estimates the probability that a channel is carrying a true signal during a given interval. If the test is 100% accurate then the encryption method is defeated. If it is partially accurate then the eavesdropper can narrow the search to a subset of the channels, which could make the memory storage and processing time requirements feasible for the eavesdropper. The encryption system design must therefore ensure that no test can exist which is approximately accurate.
Any test may be based on a difference between a statistical property of the signal's electric field compared to true optical noise. Keeping the frequency hop interval τh short helps ensure there cannot be a good test for the eavesdropper. Any function of the optical noise measured over a finite time interval shows a range of values, that is its sampling distribution. As the observation interval τh becomes shorter, then the sampling distribution of the function becomes wider, and overlaps the sampling distribution of the same function applied to a true signal. For example,
2. Noise-Rendering
The information-bearing signal must be disguised to appear like optical noise. The inphase and quadrature parts of one SOP of an optical noise field are each Gaussian noises. Optical noise contains power in both polarization states, although the optical noise could be purposely polarized for this application. The distribution of the inphase part of the information-bearing signal depends on what modulation format is used, but it is typically not Gaussian. For example, if polarization multiplexed QAM is used with Ms bits/symbol, the x-polarization of the QAM signal takes on complex values un at the symbol centers (n=0, 1, 2, . . . ), defined by the information to be transmitted. The distribution f(Re[u]) of the real part of un comprises 2M
Two ways are discussed below to convert this distribution into a Gaussian distribution, that is to noise-render the signal. The data carried by the signal must appear random. It may be precoded if necessary, for example by performing an exclusive or operation with a pseudorandom sequence derived from the key.
The first noise-rendering method begins by adding to un a pseudorandom complex variable wn, whose real and imaginary parts each follow a uniform distribution
The second noise-rendering method is to multiply un+wn by a phase factor eiθ
There are other ways of making the QAM signal appear like Gaussian noise, and there are noise-rendering methods for other classes of modulation format.
A component of the signal's electric field envelope cannot be made to be truly Gaussian by the methods above because the finite range of the D/A converters prohibits setting extreme values, while the Gaussian distribution extends to infinity. If the actual distribution deviates too much from Gaussian the eavesdropper can use this property in a test to decide if the channel being observed is likely to be the data-bearing channel, and so weakens the security of the overall encryption method. The output of the coherent channel substitution scheme may be made to resemble Gaussian noise more closely by passing it through a passive optical component which has multipath interference (MPI) longer than one symbol length. Such a component may be made in a planar waveguide system by splitting the signal into several paths of different lengths and recombining them, or by using multiple birefringent elements in sequence. The transfer function of this passive component must be reversed at the receiver, for example by the corresponding mathematical operation in the receiver's DSP. The transformation of the passive component should be made to change suddenly at intervals, according to a sequence derived from the key, otherwise if the eavesdropper correctly guesses the transformation at one point in time he can use that knowledge from then on, and the code is weakened.
3. Symbol Clock Recovery
The receiver must recover the symbol clock, the optical phase and, in the case where depolarized optical noise is used over a fiber optic link, the correct polarization transformation. These tasks are more challenging after the signal is disguised as Gaussian noise.
With a standard modulation format, the signal either contains a pilot tone of the symbol clock, or applying a non-linearity generates some symbol clock content. This is no longer the case after noise-rendering. In fact, if it were possible to see clock content so easily it could be used by an eavesdropper as a test to identify which channel carries the true information-bearing signal.
The symbol clock may be sent from transmitter to receiver outside the signal channel. A dedicated uncoded wavelength channel may be used. Alternatively, the whole broadband optical noise spectrum may be modulated with a tone at the clock frequency, so that the information-bearing channel does not appear different from the other channels. These methods may also deliver the clock to an eavesdropper, so it is more secure to rely on the clock being recovered from the noise-rendered signal.
Variations in the phase of the symbol clock are slow since very high frequency stability radio frequency sources are available, and because the change in propagation delay of long fiber optic links is slow. Once symbol clock has been acquired, its slow changes may be tracked. Initial acquisition may be completed by sweeping the clock phase coarsely over the full range and using a metric of signal quality such as bit error rate, or whether the digital signal is recovered at all, to determine which clock phase value is closest to optimum. The clock phase may then be optimized using the BER as a metric.
The propagation delay of a fiber link, and hence the clock phase, changes when the laser is hopped in frequency. The amount of delay change may be predicted exactly by knowing the chromatic dispersion of the link. This quantity may be measured at the start of communications by determining the symbol phase at several different optical frequencies.
4. Polarization Recovery
The polarization transformation between transmitter and receiver is described by three degrees of freedom, corresponding to the polar and azimuthal angles on the Poincar� sphere representation of the principle states of polarization and the rotation angle. It changes in a random fashion slowly due to movement of an optical fiber or temperature changes, perhaps varying between a few 10 s of uncorrelated SOPs in 1 second. Once the correct polarization transformation has been found any changes may be tracked. The polarization transformation at any point in time will vary over the frequency hopping band, because of the polarization mode dispersion (PMD) of the optical fiber. Furthermore, the change in polarization transformation going from one optical frequency to another will itself change randomly with time. An SOP reference may be provided by a polarized channel at a different wavelength from the signal. However, the optical frequency of the reference channel should be swept across the band in order to take into account the variation of the polarization transformation with optical frequency. Of course the frequency hopping sequence must be chosen to avoid a collision with the reference channel. Alternatively, the broadband optical noise may be polarized at the transmitter, as explained above, so that polarization recovery becomes trivial. Again, providing a polarization reference helps an eavesdropper as well as the intended recipient, and it is more secure to derive the polarization transformation from the noise-rendered signal.
The polarization transformation may be acquired by first sweeping the three SOP degrees of freedom coarsely over the full range, using a signal quality metric such as BER or the quality of the recovered optical phase, discussed below, to find the best point. A fine adjustment may then be made to find the optimum polarization transformation. This process must be completed at several optical frequencies in the FH plan, so as to gain knowledge of how PMD changes the polarization transformation over optical frequency. The FH plan must revisit all regions of the available optical spectrum sufficiently frequently to derive an update to the polarization transformation at all optical frequencies.
5. Optical Phase Recovery
The optical phase is the hardest of the three quantities to obtain. Unless an expensive narrow linewidth laser is used, the phase noise of the laser varies on a shorter timescale than the symbol clock phase or the polarization transformation. In addition, the latter two quantities do not have to be reacquired after hopping to a new frequency, given that the chromatic dispersion and the effect of polarization mode dispersion are known. Typically, when a laser tunes in an optical frequency, the phase after tuning is unknown, and a frequency error may also occur. The optical phase must be reacquired at the start of each frequency hopping interval.
The frequency offset between the signal centre frequency and the receiver local oscillator is generally within a small range, specified by the design of the transmitter and receiver. The optical phase and frequency may be acquired by a search of the frequency and phase space looking for the presence of a recognizable signal and a low BER. This approach may be slow or require a high level of parallelism in the DSP. If the time taken to acquire is longer than the available buffer in the DSP then some data will be lost at each FH interval.
When the second noise-rendering transformation described above is used it is possible to acquire the carrier phase and frequency by a more standard faster method. The electric field of one SOP of the noise-rendered signal, as seen at the receiver, after inverting the effect of the MPI passive, is
An additional benefit of using the second noise-rendering method and part of the optical phase acquisition algorithm is that it may be used with the symbol phase and polarization transformation acquisition routines as a signal quality metric. When the symbol phase and polarization transformation are close to correct, the quantity
The main issues with optical phase recovery are avoided if the signal laser in the transmitter (the add laser) and the local oscillator in the receiver are referenced to lines in a frequency-stabilized octave-spanning optical comb. The transmit site and receive site may each hold a comb generator, and these will contain identical optical frequencies to one another given that they use the same radio frequency reference. The signal laser output should be phase locked to the comb. It does not have to be the same optical frequency as one of the lines in the comb, but it has to differ from a line by a fixed frequency and no phase noise. The receiver local oscillator does not have to be phase locked to the octave-spanning comb, but its frequency and phase should be compared to one of the lines in the comb and known by the DSP. The receiver DSP then knows the exact frequency and phase of the LO compared to the signal, apart from a slowly varying contribution to the phase from the varying length of the fiber optic link with temperature. The chromatic dispersion needs to be known accurately, as it causes a jump in optical phase after a frequency hop. Given that it is phase locked to an absolute reference, the frequency hopping executed by the transmitter may then be considered to be coherent frequency hopping.
F. Appendix
1. Use of Complex Numbers to Describe Modulated Signals
Complex numbers are used to describe sine and cosine functions because this notation is a compact way of including the phase of the sine wave or cosine wave. For example the electric field is written in the form
In the above discussion are equations similar to
The power of an optical wave is given by the magnitude squared of the complex electric field, and does not have a sinusoid time dependence. So in the case of a field given by A1
2. Jones Vectors
The state of polarization of an optical signal may be described by a Jones vector. This is a two element column vector. Each element is the complex envelope of the electric field, i.e., phase information included. The top element is the component of the field in the x-direction (horizontal) and the bottom element in the y-direction (vertical). In fact x and y may be an arbitrary pair of orthogonal directions. "Optics" by E. Hecht (Addison-Wesley, 4th ed., 2001) gives a thorough account of Jones vectors.
Some Jones vectors of familiar states of polarization are listed below.
A Jones unit vector {circumflex over (p)} has the property that
When polarized light is passed through a linear optical element, the transformation of the SOP is described by premultiplying by a 2�2 matrix called the Jones matrix of the optical element.
While the present invention is described herein with reference to illustrative embodiments for particular applications, it should be understood that the invention is not limited thereto. Those having ordinary skill in the art and access to the teachings provided herein will recognize additional modifications, applications, and embodiments within the scope thereof and additional fields in which the present invention would be of significant utility.
Thus, the present invention has been described herein with reference to a particular embodiment for a particular application. Those having ordinary skill in the art and access to the present teachings will recognize additional modifications, applications and embodiments within the scope thereof.
It is therefore intended by the appended claims to cover any and all such applications, modifications and embodiments within the scope of the present invention.
Patent Citations
Referenced by
Original Image


text:
The Fund seeks to provide high current income consistent with the preservation of capital. The Fund normally invests at least 65% of its assets in securities issued or guaranteed by the US Government, its agencies or instrumentalities, and repurchase agreements pertaining to US Government securities. The Fund may also invest up to 35% of its assets in other fixed-income securities, including those issued by non-governmental issuers in the US and those issued by foreign governments. The Fund may invest up to 35% of its net assets in below-investment grade securities The Fund may also utilise other investment instruments, including options and futures.
[1] http://www.globalfunddata.com/funds/new/performance/management?variant=AllianceBernstein LP
[2] http://www.globalfunddata.com/funds/new/performance/domicile?variant=United States
[3] http://www.globalfunddata.com/funds/new/performance/fund_administrator?variant=Princeton Administrators LP
[4] http://www.globalfunddata.com/funds/new/performance/strategy?variant=Long-Term Bond
[5] http://www.globalfunddata.com/funds/new/performance/structure?variant=Closed Ended Investment Company
[6] http://www.globalfunddata.com/funds/new/performance/city?variant=New York___United States
[7] http://www.globalfunddata.com/funds/new/performance/country?variant=United States
[8] http://www.globalfunddata.com/funds/new/performance/custodian?variant=State Street Bank & Trust Co
[9] mailto:email@example.com?subject=Mail from GFM Ltd

subset: commoncrawl


text:
The Fairmount
- Reviews & Prices
- Guest Rooms
- Photos
- Amenities
- Map
|#16 in Best San Antonio Hotels
|Hotel Class 4.0-star
|Critic Rating Moderate
Guest Rating
TripAdvior Traveler Rating
Based on 99 reviews
U.S. News Review
If you want character, stay at The Fairmount (not to be confused with Fairmont). This boutique hotel occupies a Victorian-era building in downtown San Antonio, close to many of the city's most beloved attractions. The historic property is decked out in rich European fabrics and antique furniture. Guests stay in one-of-a-kind rooms. Each accommodation features its own personal decor, which some recent guests found outdated while others loved the turn-of-the-century charm. But all rooms come equipped with flat-screen TVs and complimentary wireless Internet. Some recent visitors complained of housekeeping issues, but almost everyone fell in love with The Fairmount's "Pet Concierge," Luke, a lovable golden lab with plenty of personality. After you work up an appetite playing with the property pooch, you'll have to find dining elsewhere as the on-site restaurant is closed for renovations.
- #16 in Best San Antonio Hotels
- #103 in Best Texas Hotels
Awards Received
- Fodor's Choice
Guest Rooms
- High Price
- Average Price
- Low Price
- Today
- +1 Week
- +2 Weeks
- +3 Weeks
Editor's note: Hotel information is updated periodically. If this is your property and you notice any inaccuracies, please let us know.
Similar Hotels Nearby
Hotel Contessa
<0.5 miles away
- Hotel Class4.0-star
The Westin Riverwalk
<0.5 miles away
- Hotel Class4.0-star
Marriott Plaza San Antonio
<0.5 miles away
- Hotel Class4.0-star
Hilton Palacio del Rio
<0.5 miles away
- Hotel Class4.0-star


text:
Change Location
ACE Fit Share
Tighten your abdominal muscles and protect your spine with the most effective ab exercises from the American Council on Exercise (ACE). Learn proper techniques and step-by-step instruction from America's Authority on Fitness. This large collection of exercises is also featured in complete workout routines that include full-body and at-home workouts. Whether you're looking for beginner level training or advanced fitness programs, we have something here for everyone to target core muscle groups. Choose from a wide variety of lower ab exercises, standing trunk rotations, reverse crunches and more. If you have any questions or want to hear what leaders in the industry are saying, please see our Ask the Expert section.
Fit Life Articles
With the latest wave of new consumer health technologies, fitness technology expert Ted Vickey has never been more excited about the potential for real success. Here are a few new technologies and apps that he thinks are worth exploring if you are looking for ways to stay...
If you're like most people, lack of time is your number-one reason for not working out as much as you would like to. Here's your solution: An effective 15-minute, total-body workout, which will challenge your cardio and increase your strength, even when you don't have time...
Finding time for a full workout can be tough, but fortunately you can get a lot of health benefits from short bouts of activity spread throughout your day. Here are 8 ways to add small bouts of physical activity to your day that can help you burn additional calories and...
ACE Pro Homepage
Copyright © 2015 The American Council on Exercise. All Rights Reserved.4851 Paramount Drive, San Diego, California 92123 1 (888)-825-3636


text:
I spent Good Friday in Lenoir, NC, located near the eastern edge the Appalachian Mountain range. Catholic Extension supports a parish there called St.
"The Lord hears the cry of the poor… blessed be the Lord..." Many of us know the words to that song we sing at Mass. They come from Psalm 34.
Each year, nearly 100 parishes in the United States receive Catholic Extension funding to make critical facility improvements. St.
St. Gianna's Maternity Home, in North Dakota, seems to bring to life these words, attributed to St. Francis. There are only 60 people in the tiny village of Warsaw. Many would say that it's in the middle of nowhere.
Merry Christmas from Catholic Extension!


text:
Fan-made Battlestar Gallactica game released for free
View Single Post
Registered User
Join Date: Jun 2009
Posts: 56,138
Fan-made Battlestar Gallactica game released for free
Apparently four years in the making, Diaspora: Shattered Armistice is a fan-made Battlestar Gallactica game built on the opensource Freespace 2 engine. It launched just last week and, holy smoking frak, does it look good.
You won't be able to command the Gallactica itself ' this is a game purely about the joy of zero-g dogfighting ' but you will get to hop into the ****pit of the MK VII Viper, the Raptor or the new MK VIIe strike variant and then launch from, land on, or fly loop-de-loops round Gallactica. There's multiplayer, too, where players can choose to embody either Humanity's Last Hope or indeed the God-bothering Space-Toaster Menace. The online stuff is very much in beta at the moment, so player input regarding the balance of different craft is welcomed.
Head over to
the Diaspora website
for more information on how to download the game or check out the launch trailer below to get a sense of the space-sploding thrills on offer.
View Public Profile
Find More Posts by News


text:
VENICE, Fla.
Marie Linhart, 59 of Venice, Fla. and Huron, passed away Sunday, Nov. 25, 2007.
Marie was born Jan. 12, 1948, in Lakewood, Ohio. Marie was a loving mother, wife, and homemaker. She prided herself on being the ultimate hostess to her friends and family making sure everyone was happy.
She loved playing bridge, card games, traveling, boating, fishing and golf.
Marie is survived by herhusband of 39 years, John of Venice and Huron; daughter, Beth Linhart of Brooklyn, N.Y.; son, Tom (Julie) Linhart of Tampa, Fla.; mother, Thelma Smrcina; sisters, Sharon (Jim) Reinhart of Medina, Ohio, and Joy (Mitch) Thomas ofCleveland; brothers, Al (Sue) Smrcina of Aurora, Ohio, and Mark (Dolly) Smrcina of North Ridgeville, Ohio; and sister-in-law, Diane (Tom) Dlugos of Vermilion.
She was preceded in death by her father, Elmer Smrcina.
Friends may call from 4-6 p.m. Sunday at Foster Funeral Home, 410 Main St., Huron, whereservices will be at 11 a.m. Monday. The Rev. David Aber, pastor of First Presbyterian Church, Huron, will officiate. Burial will be in Scott Cemetery, Huron.
In lieu of flowers, donations may be made to First Presbyterian Church, 225 Williams St., Huron OH 44839; or Huron Rescue Squad, 413 Main St., Huron.
Condolences may be sent tofosterfh.com.


text:
Select Local Merchants
Wiggle WagglesRead MoreJust like at the finest dining establishments, the dog meals at Wiggle Waggles are made fresh to order. Owners beg for scraps as their pups push their noses into healthy servings of muttloaf and turkey quiche, made with organic ingredients and without added salt or sugar. For dessert, dogs sate themselves with one of the bakery's hand-crafted treats, which are also organic and preservative free, and come in flavors such as reduced-fat cheese, turkey bacon, and peanut butter. They enjoy their treats perched at one of the lime-green cubes that bring pooches up to table level, or take them home to enjoy in front of the television. The eatery also caters puppy birthday parties complete with a custom organic cake, and provides pet-care services such as dog walking and sitting.500 South 3Rd St Suite 108Geneva, IL US
The Naperville Pet NannyRead MoreHi, I'm Joi, The Naperville Pet Nanny. I've been keeping just one or two guest dogs cage free over night in my Naperville home for over 30 years now. We have acres of walking trails near downtown Naperville. I was college trained in dog care and certified in dog grooming. Don't send your dog to jail while your away.7S485 Green Acres DriveNaperville, IL US
Green Trails Animal ClinicRead MoreThe team of veterinarians and technicians at Green Trails Animal Clinic make the time to personally get to know each family and pet who comes through the doors. That philosophy starts with the belief that a trusting relationship is necessary between the doctor and patients, especially when furry friends need medical care. Green Trails provides a full range of preventive care services for cats and dogs that include regular check-ups, vaccinations, and dental cleanings. For more serious ailments, the doctors also conduct emergency care and specialty treatments that include oxygen therapy and post operative recovery. And when you're away, the facility also takes animals in for boarding where they're fed, looked after, and taught how to win at chess.6430 College Rd.Lisle, IL US
The Pooper ScoopersRead MoreWhat?s brown and invariably ends up on the bottom of your shoe? The answer to that riddle is The Pooper Scoopers? main expertise: dog poop. Their trained technicians arrive at homes or commercial businesses to clear waste from yards, leaving areas less hazardous to walk through or play in. They tackle about 30,000 yards each year, and even venture inside homes to clean cats? litter boxes.218 Liszka LnOswego, IL US
Poop 911Read MoreLand mines, poop piles, dog logs—no matter what the euphemism, Poop 911 allows families to circumvent one of the unappealing parts of dog ownership. It'll clear entire yards of dog waste, and even can apply repellent to deter pets from destroying a treasured flower bed or magic beanstalk. Other add-ons include raking leaves and dog walking.10 North Martingale RoadSchaumburg, IL US
The Dog WagginRead MoreWith its cozy decor and absence of ominous cages, The Dog Waggin's welcoming facility gives busy pet owners peace of mind as their pups comfortably socialize and play. The 4,000-square-foot digs house a play room with pooch playground equipment—including slides and tunnels—a relaxing play room—characterized by fluffy pet beds—and a backyard, where dogs can caper about or stretch out and bronze their bods in time for swimsuit season. Pups are free to rest and play as they see fit with their fellow boarders, all under staff supervision during daytime outings and overnight stays. The canine caretakers also offer a number of other services, including walking, in-home sitting, and training from owner and certified dog trainer Lisa Harvey.1400 S Main St.Algonquin, IL US


text:
Freak snowstorm brings more devastation to disaster-stricken Western Mass.
For the third time in four months, Governor Deval Patrick was forced by weather-related devastation this past weekend to declare a state of emergency in Massachusetts and request government assistance from the Federal Emergency Management Association.
The late-October snowstorm dealt yet another blow to Western Mass. communities who are still recovering from damages due to Hurricane Irene and a series of tornadoes on June 1. As of Monday morning, utility companies scrambled to restore electricity to a total of about 671,000 powerless customers throughout Massachusetts, while about 1,300 residents are residing in 38 shelters across the state.
I think a lot of people were trying to stick it out, but now its getting too cold, said Dawn Leaks, assistant director of the Pioneer Valley Chapter of the American Red Cross.
(See related coverage.)
In Springfield, public schools have been cancelled for the week and by Monday afternoon city residents seeking emergency shelter exceeded the 400-person capacity of the gymnasium and cafeteria at Central High School, causing the city to provide overflow van transportation to the American Red Cross regional shelter at Chicopee High School. The number of people in need of food, warmth and shelter from the noreaster has already exceeded the roughly 350 people who stayed at MassMutual Center in the aftermath of the June 1 tornado.
It just goes to show the devastation of this storm, said Helen R. Caulton-Harris, Springfields city director of health and human services. It really does show how widespread and impactful this has been for residents of the city of Springfield.
State officials report that an unprecedented 1,500 crews were working to restore power, but even so, some residents may be without power until Friday. As of 4 p.m. Monday, 459,809 customers remained without electricity, including 303,683 for National Grid, 112,559 for Western Massachusetts Electric, 34,506 for NStar, and 9,061 for Unitil. Restoration time estimates are available on company websites.
The governor has confirmed three fatalities, including Jeffrey Mattarazzo, 20, of Springfield, who was electrocuted by a downed power line; a Hatfield resident who died from carbon monoxide poisoning due to an improperly ventilated generator; and an elderly woman in Lunenberg who was killed in a house fire in an area that was without power. Falmouth police have also reported the storm played a role in a car crash that killed two people.
In addition to Central and Chicopee High Schools, emergency shelters throughout Western Mass. are located in East Longmeadow at Birchland Park Middle School, Hampdens Green Meadows School, Westfield State Universitys Juniper Park School and Scanlon Hall, Worcesters Forest Grove Middle School, Sturbridges Tantasqua High School and the Fitchburg Senior Center. An American Red Cross regional shelters are located in the cafeteria at Northamptons Smith Vocational and Agricultural High School, Belchertown High, Monsons Quarry Hill School, Granby High, The Armory in Orange, Palmers Converse Middle School and War Memorial in Holyoke. Noble Hospital of Westfield is also providing shelter services to the elderly and those with medical problems.
For more information and locations of emergency shelters that provide heat, food and cots for sleeping call the states 211 help number.
The author is solely responsible for the content.
About the authors
Students in Steve Fox's Investigative Journalism & the Web class at UMass-Amherst have teamed up with the Globe to take a close-up look at the painful process of rebuilding from the June 2011 tornadoes that killed four and devastated communities in the Springfield area. Their work will also appear in the Boston Globe. Steve joined the journalism faculty at UMass-Amherst in 2007 and has 25 years of experience as an editor and reporter for print and online publications, including 10 as an editor at The Washington Post's award-winning website.


text:
David's Sunday Forecast 2.16.14UPDATED 5:32 AM PST Feb 16, 2014
Meteorologist David Biggar has the latest on the mostly sunny skies expected by the afternoon.
More Video
CommentsThe views expressed are not those of this site, this station or its affiliated companies. By posting your comments you agree to accept our terms of use.blog comments powered by Disqus


text:
Images of the devastation in Moore, Okla. (Image editing by Mike Corones/Digital First Media)
Article Comments
(John Leyba, The Denver Post)
SportsHochman: Trading Troy Tulowitzki is like benching Kate Hudson: It hurts so good
The Rockies are Kate Hudson, the lovable actress who keeps churning out just unwatchable abominations - and yet dazed glory-days devotees still point back to that one good year.
Speed the 150-year-old tortoise dies at San Diego Zoo
SAN DIEGO (AP) — One of San Diego's oldest residents has died. The Los Angeles Times reports (http://lat.
Jewish officials protest art installation at Polish museum
WARSAW, Poland (AP) — Jewish officials are furious over a video installation at a Polish museum that shows naked men and women playing a game of tag in a gas chamber. Full Story


text:
Phoenix Mercury
Kim Kardashian falls over junk at family's yard sale
The phrase "you break it, you buy it" probably ran through Kim Kardashian's head after she took a tumble while walking around her family's charity yard sale on Sunday.
Don't worry -- as if you were -- the reality star didn't seem to get hurt; an over-sized lamp shade broke her fall. She quickly brushed it off with a laugh and a hug from BFF Jonathan Cheban. Of course, photographers captured the embarrassing moment on camera.
According to TMZ, the sale was organized by Kim's sisters Kendall and Kylie Jenner, along with her mom, Kris, to support the organization No Kid Hungry.
Kim's spill is indirectly promoting the charity, so at least she has that going for her. We're laughing with you, Kim.
Most Popular
Mercury Audio
- Jim Pitman, Phoenix Mercury General ManagerPhoenix Mercury general manager Jim Pitman joins Paul and Wolf.
- Jim Pitman, Suns Executive Vice President & Phoenix Mercury GMThe Mercury GM says the team will stay competitive even with no Diana Taurasi this season.
- Brittney Griner, Phoenix MercuryPhoenix Mercury center Brittney Griner speaks on WNBA uniform changes and her new memoir.


text:
Anna Fedoseeva joined us onboard the Akademik Sergey Vavilov in Antarctica this season in the dining room/hospitality team.
Those of you who joined our Antarctic season opener with artists Brett Jarrett (who will be joining the Kapitan Khlebnikov in the Arctic 2010) and Neil Roberts may have seen how Anna took the opportunity to learn from our two guests. Later in the voyage we realised how talented Anna was when, after a little persuasion, she let us see one of her paintings.
At the end of the first voyage Anna very kindly offered to donate one of her works for the Albatross auction. As a 'thank you', Peregrine's Polar Manager took Anna shopping in Ushuaia for paints, brushes and canvasses. Whilst searching out the one art store in Ushuaia he discovered that Anna's formal education, back in Russia, was as an artist/sculptor. Anna continued to paint throughout the season and continued to donate her art helping Peregrine raise over $65,000 towards our 'Get Albatross Off the Hook' fund.
Not only did Anna's painting donations greatly contribute to the cause, but a few lucky passengers are now owners of her fabulous works of art which include wonderful paintings of the Antarctic landscape and wildlife they experienced onboard. To view a selection of some of Anna's paintings please click here.
We hope that Anna continues to add to our special program. A big thank you to Anna and to those of you who purchased items and donated money.


text:
LARWILL — Larwill residents will soon incur an increase on their monthly utility billing as the town's sewer ordinance has been amended. Town attorney, Greg Hockemeyer, made the changes to the ordinance which outlines a 14.3 percent rate hike. The monthly rate for a single family dwelling will increase from $35 to $40. A copy of the amended rate ordinance is available for inspection at the clerk's office during posted business hours.
COLUMBIA CITY  — With doughnuts to share, the Salvation Army of Whitley County celebrated 75 years of service with an open house. Members of the community were invited to visit the new location that is now inside First Church of God off DePoy Dr in Columbia City.
The organization has grown in support and in its effort to extend a helping hand to those in need. But there are still residents of Whitley County who are not aware of the Salvation Army's willingness to serve them.
LARWILL — Locally-based contract manufacturer Red Star Manufacturing, Inc. recently collaborated with Whitko High School to support component manufacturing for a custom-ordered 10-ton plastic injection molding machine.
In late 2011, Red Star owner Scott Werstler approached Whitko Engineering and Welding Technology teacher Jay Ocken about providing his students with hands-on experience with tools and techniques in component manufacturing.
MCKINNEY, Texas — The Columbia City man jailed in April in Collin County, Texas on charges of money laundering has been released on bail, according to court officials in that county.
According to Tim Wyatt, the attorney for Duane Ducharme, 70, posted a $40,000 surety bond on Wednesday.
Ducharme is represented by McKinney, Texas-based attorney Gregg Gibbs. Wyatt said Friday that an examining trial is scheduled there May 25.
"I can find nothing that says his (Ducharme) whereabouts, and I don't have the conditions of his bond.
Ducharme was booked April 13.
COLUMBIA CITY — The Highway Department is laying out plans for their summer sealing program and the continuation of dust control efforts.
"It's when we get the most calls," said Mike Barton, highway department superintendent. "They want to know which roads will be done first and second and if there are roads that are going to be done at all."
"We'll go out, and especially the roads we've milled, we want to get them out of any possible dust they've seen since last fall," said Barton.
Barton said the Highway Department has not seen as much dust on the roads as they expected.
COLUMBIA CITY — Despite an impressive 10-run inning by Columbia City, Whitko held on for a 16-13 win over the Eagles on their own field Friday night in Columbia City.
Whitko jumped out to a 13-3 lead at the top of the fourth inning. Fearing the possibility of being beat by the 10-run-rule, Columbia City retaliated with a 10-run fourth frame to tie the score at 13.
But that was the end, as the Eagles didn't score another run for the final three innings, while Whitko tacked on three more in the high-scoring game.
CHURUBUSCO — Churubusco's boys and girls track teams hosted the Northeast Corner Conference meet Friday night.
The boys team placed third out of 10 teams, and the girls came in fourth.
Fairfield was the boys NECC title winner, while Westview received the honors for the girls.
Churubusco continued to control the throwing events, with Heather Monk taking first-team all-conference in both the shot put and discus. Monk's sister, Katie, got second in the discus and third in the shot put.
Austin McClure dominated the boys throws, winning the discus and taking second in the shot put.
NEW HAVEN — Columbia City's boys golf team posted its best score of the season Thursday night at Whispering Creek.
The Eagles won with a 156 over the Bulldogs, who shot a 177.
Columbia City's previous low was 166, 10 strokes higher than the Eagle's score on Thursday.
Eagle Drew Burnsworth shot his best score of the season, 35, earning medalist honors.
"It was good to see Burnsworth break out and finish a round well," Thompson said. "It was huge."
Derek Philbee fired a 39, his first score under 40 this season.
"He's been playing well for us," Thompson said.
COLUMBIA CITY — The county council motioned to approve the president of the Whitley County EDC Alan Tio's request for a revolving loan fund (RLF) Wednesday.
The request was made for a small business called Neptune's Keep.
Jacob Bartlett, the owner of the agricultural shrimp farming business in southern Indiana, said he wants to expand, and he is considering locating in Whitley County.
Bartlett said he has been raising White Pacific shrimp indoors for the past two years, with successful growth in the business.
CHURUBUSCO — After prom is supposed to be fun. But some Churubusco students are having way too much fun with what happened right before prom and getting national attention for it.
Thirteen teens were dressed in their finest and getting pictures taken before Churubusco Senior High School's prom last Saturday at the home of the Blake family when the deck they were standing on collapsed.
The students and their parents had decided to meet at Chandler Blake's home just across from the I.U. Pond north of Churubusco on U.S. 33.


text:
Restored 1950's era 3/4 Midget Race Car with Crosley 4 cylinder engine and three-speed manual transmission. This race car was found in a field... More
- Restored- 44 CI OHV inline 4-cylinder engine- 3-speed transmission- Maroon accented with Cream colored wheels and Tan interior- 4-wheel drum brakes- Fitted with... More
1952 Crosley Super production#7 of of only a handful cars left in existence older restoration looks and drives excellent. unique little car that's fun... More
Mazda B-2200 Truck Inline 4 Cylinder Engine... More
See at Mecum Kansas City Auction on Aprl 25th! 1952 Crosley Kiddie Fire Dept. Hook and Ladder Fire Truck The Crosley was an U.S. automobile manufactured by Crosley... More
A-1 HUGE selection of used and remanufactured parts, we do restorations, MC & Visa welcomed, if youre looking for a Crosley, call us. Yankee... More


text:
To provide investors with above average dividend income and long-term capital growth through investing predominantly in S&P 500 constituents. The following will apply: - The Company will invest predominantly in S&P 500 constituents with a maximum single stock weighting of 10% of gross assets at the time of investment. - A maximum of 20% of gross assets can be invested in fixed income investments and the Company will also be able to invest in Canadian stocks and US mid and small cap stocks to provide for diversified sources of income.
[1] http://www.globalfunddata.com/funds/new/performance/management?variant=Aberdeen
[2] http://www.globalfunddata.com/funds/new/performance/domicile?variant=United Kingdom
[3] http://www.globalfunddata.com/funds/new/performance/fund_administrator?variant=BNP Paribas Securities Services, Dublin
[4] http://www.globalfunddata.com/funds/new/performance/strategy?variant=US Large-Cap Blend Equity
[5] http://www.globalfunddata.com/funds/new/performance/structure?variant=Closed Ended Investment Company
[6] http://www.globalfunddata.com/funds/new/performance/city?variant=London___United Kingdom
[7] http://www.globalfunddata.com/funds/new/performance/country?variant=United Kingdom
[8] http://www.globalfunddata.com/funds/new/performance/custodian?variant=Bank of New York Tr & Depositary Co. Ltd
[9] mailto:firstname.lastname@example.com?subject=Mail from GFM Ltd


text:
The NFL is supposed to be testing for HGH among its players by now. Back in 2011, the NFLPA and the NFL agreed to blood-testing, but both have dragged their feet in terms of implementing the tests. According to one player speaking to the Milwaukee Journal-Sentinel, the use of human growth hormone as at an all-time high in the league: "It's like clockwork nowadays," he said, estimating 10-15 players on each team use the banned substance. "Not tested and it's easy to get. Nowadays, dude? In 2013? (Expletive) yeah. I'm just being real." That number of players is an extremely high and if that estimation is accurate, that would be roughly about 18-20 percent of the league taking what is banned substance. We are inclined to believe that number might be more in the 10-15 percent range. That being said, having at least five guys on a single team is quite a bit. It is more likely that the use is more spotty around the league, with some teams having many more, and some teams with zero players using it. The actual benefits of HGH in terms of being a performance-enhancing drug are still in question. There is not a [...]
NFL News
Delivered to your inbox
You'll also receive Yardbarker's daily Top 10, featuring the best sports stories from around the web. Customize your newsletter to get articles on your favorite sports and teams. And the best part? It's free!
|Best of Yardbarker
|NFL News
|MLB News
Today's Best Stuff
For Bloggers
Join the Yardbarker Network for more promotion, traffic, and money.
Company Info
What is Yardbarker?
Yardbarker is the largest network of sports blogs and pro athlete blogs on the web. This site is the hub of the Yardbarker Network, where our editors and algorithms curate the best sports content from our network and beyond.
|© 2015 Yardbarker, Inc. All rights reserved. Use of this website (including any and all parts and components) constitutes your acceptance of these Terms of Use and Privacy Policy. (What's New?)


text:
Donald Duck Presents (Series)Donald Duck Presents (Series) (1983) Cartoon Series
This page has been viewed 45 times this month, and 1900 times total.
- Donald Duck Presents Cartoon SeriesSeries
- Traditional Animation
- Left Coast Television, No-g Production
- Cartoon Characters: Donald Duck, Mickey Mouse, Minnie Mouse, Goofy, Chip 'n' Dale, Pluto.
- Directed By Various.
- Produced By Walt Disney.
- Written By Various.
- Series Began Airing on September 01, 1983.
- Originally Aired on The Disney Channel (USA).
- Running Time: 30 minutes.
- Color
Cartoon Summary:
Donald Duck hosts this series of classic cartoons edited into half-hour compilations first aired on The Disney Channel in 1983. The show was added to the Disney... (more)
Cartoon Video:
Sorry, we do not have a video of Donald Duck Presents (Series). If you have one, or know of one on Youtube, Vimeo or any other site, Let Us Know
Submit Additional Information:
Do you have anything to add to this page? Have we made any mistakes... or do you have any additional information about Donald Duck Presents (Series)? If so, we would love to hear from you. Please send us a quick note with your additions or corrections to this page, and we will make the corrections as soon as possible!
Cartoon Comments:
Do you love Donald Duck Presents (Series), or do you think it is the worst cartoon ever? Let us know what you think! Surely you have an opinion... so share what you think. Take a minute and post your own comments about this cartoon here.


text: I admit, I am a choice hotels fan. They have treated me right 99% of the time and the property's are clean and the beds great. The Sleep Inn in El Paso is exactly that. Very good beds, New and clean property and a decent breakfast. It is a little hard to find the first time and you need a... More


text:
P.F. Chang's Confirms Credit and Debit Card Breach
Latest News
NEW YORK (CBSDC/AP) — P.F. Chang's is confirming that data from credit and debit cards used at its restaurants was stolen.
The company says it learned about the security breach on Tuesday from the U.S. Secret Service and began investigating the breach with the agency and a team of forensics experts. It found that credit card and debit cards were exposed, but it doesn't know yet when it started happening and which stores were affected.
The company didn't say how many cards were affected.
It is now using manual credit card imprinting devices at all its P.F. Chang's restaurants to process card payments while the investigation continues.
Scottsdale, Arizona-based P.F. Chang's China Bistro Inc. owns its namesake restaurants and Pei Wei Asian Diners. There are more than a dozen P.F. Chang's restaurants in the Baltimore and Washington region and 209 nationwide.
More Business News
- NYC: Whole Foods Mislabels Prepackaged Items, Overcharges
- Ford Jumps Into the Car-Sharing Pool With Pilot Program
- Millennials Causing Dramatic Decline In Tuxedo Sales
- McDonald's to Simplify Structure, Focus on Customers
(TM and Copyright 2014 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2014 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)


text: tag:blogger.com,1999:blog-8254272216866737058.post6110821652597814830..comments2015-06-25T05:51:50.514-06:00Comments on Καθολικός διάκονος: God is merciful and worthy of praiseDeacon Scotthttp://email@example.com:blogger.com,1999:blog-8254272216866737058.post-38468739842150211952014-08-18T07:47:03.780-06:002014-08-18T07:47:03.780-06:00Well written, Scott! The quote you use from Benedi...Well written, Scott! The quote you use from Benedict's Jesus trilogy puts me in mind of the following: In one verse, Jesus says, "The Kingdom of God is *among* you," and in another verse he says, "The Kingdom of God is *within* you." I see no disparity between these two statements, nor do I think Benedict or you would, either. I like the way that you point out that Jesus challenges his Jewish disciples to shed their bigotry against Gentiles, and at the same time holds up the behavior of this Gentile (and *woman*, no less!) as a model to be followed by them. In our modern, Western culture, we often miss how revolutionary such statements by Jesus really were in his time and culture.Craig Helmshttp://firstname.lastname@example.com