text:
A method and apparatus for computing GPS receiver position without using absolute time information transmitted by the satellite or by an alternative source of timing available at the GPS receiver. The GPS receiver is contained in an integrated receiver that also includes a wireless communication transceiver, but does not have access to an accurate source of absolute time information. The wireless transceiver communicates through a wireless network to a server. The GPS receiver measures satellite pseudoranges and uses the wireless communication transceiver to send the pseudoranges to the server. The server fits the pseudoranges to a mathematical model in which the GPS receiver position and the absolute time are unknown parameters. The server then computes a position and absolute time that best fit the model, thus yielding the correct position for the GPS receiver, and the absolute time at which the pseudorange measurements were made.
1. A method for calculating position of a satellite signal receiver, comprising:
providing pseudoranges that estimate the range of the satellite signal receiver to a plurality of satellites;
providing an estimate of a position of the satellite signal receiver;
providing an estimate of time;
relating the pseudoranges, the position estimate, and the time estimate to a plurality of position and time variables; and
computing at least one of absolute position and absolute time by updating only a subset of the position and time variables.
2. The method of
3. The method of
4. The method of
5. The method of
6. The method of
7. The method of
forming a-priori pseudorange-residuals;
forming a mathematical model relating the a-priori pseudorange-residuals to the subset of position and time variables; and
computing updates of the subset of estimated position and time variables that fit the mathematical model.
8. The method of
9. The method of
10. The method of
11. The method of
ui is the a-priori range-residual, for one satellite;
ρi is the pseudorange for a satellite i;
x, y and z are three coordinates of position updates;
tc is a common mode error update;
ts is an absolute time of reception update; and
∂ denotes the partial derivative; and
wherein at least one of the variables in the set x, y, z, tc, and ts is decoupled from the other variables to produce the subset of position and time variables.
12. The method of
13. The method of
14. The method of
15. The method of
16. The method of
17. A method for calculating position of a satellite signal receiver comprising:
providing pseudoranges that estimate the range of the satellite signal receiver to a plurality of satellites;
providing an estimate of a position of the satellite signal receiver;
computing an absolute position of the satellite signal receiver by updating the position estimate using a model relating the pseudoranges and the position estimate, the model being independent of absolute time.
18. The method of
19. The method of
forming a-priori pseudorange-residuals;
forming a mathematical model relating the a-priori pseudorange-residuals to the updates of the position estimate; and
computing updates of the position estimate that fit the mathematical model.
20. The method of
21. The method of
22. The method of
ui is the a-priori range-residual, for one satellite;
ρi is the pseudorange for a satellite i;
x, y and z are three coordinates of position updates;
tc is a common mode error update;
ts is an absolute time of reception update; and
∂ denotes the partial derivative; and
wherein the variable ts is decoupled from the other variables.
23. A system for computing position of a satellite signal receiver comprising:
a mobile device comprising a satellite signal receiver and a wireless transceiver,
a server being in wireless communication with the mobile device;
where the satellite signal receiver computes pseudoranges that estimate the range of the satellite signal receiver to a plurality of satellites, and the wireless transceiver transmits the pseudoranges to the server;
where the server relates the pseudoranges, a position estimate, and a time estimate to position and time variables and computes at least one of absolute position and absolute time for the satellite signal receiver by updating only a subset of position and time variables.
24. The system of
25. The system of
This application is a continuation-in-part of U.S. patent application Ser. No. 09/715,860, filed Nov. 17, 2000 now U.S. Pat. No. 6,417,801, which is herein incorporated by reference.
1. Field of the Invention
The invention relates to satellite-based position location and, more particularly, the invention relates to a method and apparatus for time-free processing of global positioning system (GPS) signals.
2. Description of the Related Art
Global Positioning System (GPS) receivers normally determine their position by computing time delays between transmission and reception of signals transmitted from satellites and received by the receiver on or near the surface of the earth. The time delays multiplied by the speed of light provides the distance from the receiver to each of the satellites that are in view of the receiver. The GPS satellites transmit to the receivers satellite-positioning data, so called "ephemeris" data. In addition to the ephemeris data, the satellites transmit to the receiver absolute time information associated with the satellite signal, i.e., the absolute time signal is sent as a second of the week signal. This absolute time signal allows the receiver to unambiguously determine a time tag for when each received signal was transmitted by each satellite. By knowing the exact time of transmission of each of the signals, the receiver uses the ephemeris data to calculate where each satellite was when it transmitted a signal. Finally, the receiver combines the knowledge of satellite positions with the computed distances to the satellites to compute the receiver position.
The process of searching for and acquiring GPS signals, and reading the ephemeris and related data, including absolute time, for a multiplicity of satellites is time consuming and introduces unacceptable delays in computing the receiver position. In addition, in many situations, there may be blockage of the satellite signals. In these cases the received signal level can be too low to demodulate and derive the satellite data without error. However, in these degraded signal situations, the receiver is capable of tracking the satellite signals, and measuring time delays (and hence distance), if an external source of ephemeris and absolute time is available.
Several innovations have been made to provide "GPS Aiding" that consists of external sources of ephemeris (or equivalent) data and absolute time information. The aiding information is transmitted to the GPS receiver using some alternative form of communication (usually wireless, such as cellular data channels). Thanks to the use of GPS Aiding, GPS receivers can operate in areas where signal levels are too low for traditional GPS to function properly.
All GPS Aiding, thus far invented, requires accurate external knowledge of the absolute time, so that the satellite positions can be accurately determined. The absolute time is required to an accuracy of between 1 millisecond and 10 milliseconds. Unfortunately, there are desired implementations of GPS Aiding where absolute time cannot easily be obtained to this accuracy at the GPS receiver. For example: the AMPS cellular phone system does not support time information; nor (currently) does the North American TDMA cellular phone system. The GSM cellular phone system supports timing information, but may have different time references in different geographical regions. In these situations it is desirable to provide a method for computing GPS receiver position without knowing the absolute time.
More specifically, Global Positioning System (GPS) receivers receive GPS signals transmitted from orbiting GPS satellites containing unique pseudo-random noise (PN) codes. The GPS receivers determine the time delays between transmission and reception of the signals by comparing time shifts between the received PN code signal sequence and internally generated PN signal sequences.
Each transmitted GPS signal is a direct sequence spread spectrum signal. The signals available for commercial use are provided by the Standard Positioning Service. These signals utilize a direct sequence spreading signal with a 1.023 MHz spread rate on a carrier at 1575.42 MHz (the L1 frequency). Each satellite transmits a unique PN code (known as the C/A code) that identifies the particular satellite, and allows signals transmitted simultaneously from several satellites to be received simultaneously by a receiver with very little interference of any one signal by another. The PN code sequence length is 1023 chips, corresponding to a 1 millisecond time period. One cycle of 1023 chips is called a PN frame. Each received GPS signal is constructed from the 1.023 MHz repetitive PN pattern of 1023 chips. At very low signal levels the PN pattern may still be observed, to provide unambiguous time delay measurements, by processing, and essentially averaging, many PN frames. These measured time delays are called "sub-millisecond pseudoranges", since they are known modulo the 1 millisecond PN frame boundaries. Once the absolute time delay can be calculated, by resolving the integer number of milliseconds associated with each delay to each satellite, then one has true, unambiguous, pseudoranges. The process of resolving the unambiguous pseudoranges is known as "integer millisecond ambiguity resolution".
A set of four pseudoranges together with a knowledge of the absolute times of transmissions of the GPS signals and satellite positions at those absolute times is sufficient to solve for the position of the GPS receiver. The absolute times of transmission are broadcast from the satellites in the Navigation Message, which is superimposed on the 1.023 MHz PN code at a lower, 50 Hz, data rate. This 50 Hz signal is a binary phase shift keyed (BPSK) data stream with bit boundaries aligned with the beginning of the PN frame. There are exactly 20 PN frames per data bit period (20 milliseconds). The 50 Hz signal contains data bits describing the GPS satellite orbits, satellite clock corrections, time of week information, and other system parameters.
The absolute times associated with the satellite transmissions are determined in conventional GPS receivers by reading the Time of Week (TOW) data in the Navigation Message of the GPS signal. In the standard method of time determination, a conventional GPS receiver decodes and synchronizes to the 50 baud data stream. The 50 baud signal is arranged into 30-bit words grouped into subframes of 10 words, with a length of 300 bits and a duration of six seconds. Five subframes comprise a frame of 1500 bits and a duration of 30 seconds, and 25 frames comprise a superframe with a duration of 12.5 minutes. A superframe contains the complete Navigation Message. The data bit subframes that occur every six seconds contain bits that provide the TOW to six second resolution. The 50 baud data stream is aligned with the C/A code transitions so that the arrival time of a data bit edge (on a 20 ms interval) resolves the absolute transmission time to the nearest 20 milliseconds. Precision synchronization to bit boundaries can resolve the absolute transmission time to one millisecond or less.
The absolute times associated with the satellite signals are determined in Wireless Aided-GPS receivers by having an external timing source that is calibrated to GPS time then using this time to provide a precise time tag at the time of reception of the satellite signal. The time of reception minus the pseudorange gives the absolute time of transmission for each satellite (with the pseudorange expressed in time units, reflecting the transmission-reception time delay).
The absolute times of transmission are needed in order to determine the positions of the satellites at the times of transmission and hence to determine the position of the GPS receiver. GPS satellites move at approximately 3.9 km/s, and thus the range of the satellite, observed from the earth, changes at a rate of at most �800 m/s. Absolute timing errors result in range errors of up to 0.8 m for each millisecond of timing error. These range errors produce a similarly sized error in the GPS receiver position. Hence, absolute time accuracy of 10 ms is sufficient for position accuracy of approximately 10 m. Absolute timing errors of much more than 10 ms will result in large position errors, and so typical GPS receivers have required absolute time to approximately 10 millisecond accuracy or better.
Note that absolute timing errors also introduce errors as a result of the GPS satellite clock drift, but these are so much smaller than the satellite position error that they can be ignored for the purposes of this explanation (GPS clocks drift typically less than 0.1 nanoseconds per second, and the observed range to the satellite is affected by the GPS clock drift multiplied by the speed of light, this error is less than 0.03 m/s, about 25 thousand times smaller than errors caused by changes in satellite position).
There is another time parameter closely associated with GPS positioning, this is the sub-millisecond offset in the time reference used to measure the sub-millisecond pseudorange. This offset affects all the measurements equally, and for this reason it is known as the "common mode error".
The common mode error should not be confused with the absolute time error. As discussed above, an absolute time error of 1 millisecond leads to range errors of up to 0.8 meters while an absolute time error of 1 microsecond would cause an almost unobservable range error of less than 1 millimeter. However, a common mode error of 1 microsecond causes a pseudorange error of 1 microsecond multiplied by the speed of light, that is 300 meters.
Because common mode errors have such a large effect on pseudoranges, and because it is practically very difficult to calibrate the common mode error, traditional GPS receivers treat the common mode error as an unknown that must be solved for, along with position, once sufficiently many pseudoranges have been measured at a particular receiver. However, no traditional GPS receivers solve for absolute time error instead relying on the fact that they know absolute time to the required accuracy (of 10 milliseconds or better).
Therefore, a need exists in the art for a method and apparatus that processes GPS signals without using absolute time.
The present invention is a method and apparatus for computing GPS receiver position without using absolute time information transmitted by a satellite or by an alternative source of timing available at the GPS receiver. In an embodiment of the invention, the GPS receiver is contained in an integrated receiver that also includes a wireless communication transceiver, but does not have access to an accurate source of absolute time information. The wireless transceiver communicates through a wireless network to a server. The GPS receiver measures satellite pseudoranges and uses the wireless communication transceiver to send the pseudoranges to the server. The server fits the pseudoranges to a mathematical model in which the GPS receiver position and the absolute time are unknown parameters. The server then computes a position and absolute time that best fit the model, thus yielding the correct position for the GPS receiver, and the absolute time at which the pseudorange measurements were made.
So that the manner in which the above recited features of the present invention are attained and can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings.
It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
FIG. 1 depicts a block diagram of apparatus for computing a GPS receiver location without knowledge of absolute time;
FIG. 2 depicts a flow diagram representing the operation of the apparatus of FIG. 1;
FIG. 3 depicts a flow diagram representing a method of computing pseudoranges in accordance with the invention;
FIG. 4 depicts a flow diagram representing a method of computing receiver position and absolute time in an alternative embodiment of the invention;
FIGS. 5A and 5B graphically depict a grid (5A) used for producing the residual magnitudes (5B) of position error; and
FIG. 6 depicts a graph of the residual time error used in computing an absolute time.
The invention is a method and apparatus for determining position and time in a global positioning system (GPS) without having access, at the GPS receiver, to absolute time information. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be evident, however, to one skilled in the art that the present invention may be practiced without these specific details.
FIG. 1 depicts one embodiment of the present invention comprising an integrated mobile receiver 102 coupled to a server 121 via a wireless link 150. A GPS receiver 108 is contained in the integrated receiver 102 along with a wireless communication transceiver 112. The GPS receiver 108 measures only sub-millisecond pseudoranges with respect to GPS satellites that are in view of the receiver 108, and then sends these sub-millisecond pseudo-ranges to a server 121 using a wireless communication link 150. The server 121 forms an approximate, a-priori estimate of the GPS receiver position from the known location of a wireless tower 118 used to receive the wireless communication. The server 121 also allocates a time tag from its own real time clock, thus creating an a-priori estimate of the absolute time at which the GPS receiver 108 received the GPS signals from the satellites. If the a-priori position is within 100 km of the true position, and the a-priori absolute time of reception is within one minute of the true (unknown) time of reception, then the server 121 can resolve the integer milliseconds, thus turning the sub-millisecond pseudoranges into true pseudoranges.
Next, the server 121 uses the pseudoranges to solve for the unknown receiver position and absolute time. The server comprises a central processing unit (CPU) 122, a server clock 124, a tower location database 128, CPU support circuits 152, and memory 154. The support circuits comprise well-known circuits that facilitate operation of the CPU such as clock circuits, cache, power supplies, I/O interface circuits, and the like. The memory 154 may be random access memory, read only memory, removable storage, hard disk storage, or any combination of these memory devices.
In one embodiment of the invention, the common mode error is assumed to be totally unknown at the server 121. In the one embodiment of the invention, the server 121 assumes an a-priori common mode error of zero, although it will be understood that any other a-priori common mode error could be used, with no change in the results. With the five a-priori estimates of the unknown parameters (3 coordinates of position, 1 absolute time, 1 common mode error) the server 121 creates a mathematical model relating the measured pseudoranges and a-priori information to the unknown parameters. The mathematical model can be written as a linear equation, which, when solved, yields the correct position and absolute time.
More specifically, GPS signals 104 from a plurality of satellites (not shown) are received at the GPS antenna 106. The received signals are coupled to the GPS receiver 108. The GPS receiver 108 processes the GPS signals to form sub-millisecond pseudoranges on path 110, which are coupled to the communication transceiver 112 and transmitted from the communication antenna 116 through a wireless network such as a cellular telephone network. The transmission from the integrated receiver 102 is received by a nearby radio tower 118, e.g., a cellular telephone tower. The sub-millisecond pseudoranges and the radio tower ID are sent from said radio tower 118 to the server 121. In the server 121 the server clock 124 is used to provide a time-tag when the sub-millisecond pseudoranges are received at the server. The server 121 passes the radio tower ID along path 126 to a tower location database 128, and extracts a location for the tower from the database 128. The tower location is coupled to the CPU 122 along path 130.
The satellite ephemeris data, for all satellites represented by the sub-millisecond pseudorange data, is provided to the server from some external source 125 (such as another GPS receiver located in the vicinity of the server with a clear view of the sky, or some other source such as a network of GPS receivers). Note that, for simplicity, the term "ephemeris" is used to mean the satellite orbital parameters, as well as the satellite clock parameters. The CPU 122 of the server 121 combines the sub-millisecond pseudoranges, radio tower location, server time, and ephemeris to form the correct GPS receiver position and absolute time of reception of signals at the GPS receiver 108.
The apparatus above assumes that the GPS receiver 108 is not capable of reliably receiving the absolute time information and ephemeris data, i.e., the GPS receiver is used indoors, such that the processing of ephemeris data is accomplished in the server 121. However, in some instances, rather than having the pseudo range data supplied to the server, the server (or some other source) can supply the ephemeris data and clock signal to the mobile device 102 and the mobile device can perform the position calculation. In such an embodiment of the invention, a CPU and clock (similar to 122 and 124) are located in the mobile device 102 to facilitate signal processing in the same manner as is described with respect to the server 121.
FIG. 2 is a flowchart illustration of the process 200 that is performed by the server CPU 122 of FIG. 1. At step 202, the server clock signal is used to provide an a-priori estimate of the absolute time of reception of the GPS signals at the GPS receiver. It will be understood that the use of the server clock is one embodiment used to exemplify the current invention and, in general, the a-priori estimate of time could come from a time source other than the server clock. The present invention is applicable irrespective of the source, or quality, of the a-priori estimate of absolute time. To simplify the exposition, this particular embodiment is assumed to have a server clock that provides a time tag within one minute of the actual absolute time of reception of the GPS signals at the GPS receiver. It will be understood that this simplifying assumption, while often true in practice, is not a necessary part of the invention, and has been used here only to simplify the explanation of the invention. Later in this specification, this simplifying assumption is removed.
At step 206, the tower location is provided to the CPU as an a-priori estimate of the GPS receiver position. It will be understood that the use of the tower location is just one embodiment of any number of a-priori positions that could be used (for example: a previously calculated position for the same GPS receiver 108 could be used as an a-priori position, or a combination of positions of recently used towers, or the a-priori position could simply be guessed). The present invention is applicable irrespective of the source, or quality, of that a-priori position. To simplify the exposition, this particular embodiment is assumed to have an a-priori position that is within 100 km of the true position of the GPS receiver 108. It will be understood that this simplifying assumption, while often true in practice, is not a necessary part of the invention, and has been used here only to simplify the explanation of the invention. Later in this specification this simplifying assumption is removed.
At step 204 and 208, the sub-millisecond pseudoranges and ephemeris for the appropriate satellites that are in view of GPS receiver are also provided as inputs to the process 200.
At step 210, the sub-millisecond pseudorange integers are resolved by a process described below with respect to FIG. 3. Having resolved the sub-millisecond pseudorange integers, the process creates full pseudoranges.
At step 212, the expected pseudoranges are formed. These expected pseudoranges are the pseudoranges that would be measured if all the a-priori parameters (a-priori position, a-priori absolute time of measurement, and a-priori common mode error) were in fact the actual values of these parameters. The expected pseudoranges are denoted ri, the index i denotes the appropriate satellite.
At step 214, the a-priori pseudorange residuals are formed, these residuals are defined as the difference between the measured pseudoranges (denoted ρi) and the expected pseudoranges (ri). The a-priori pseudorange residuals are denoted ui.
At step 216 a mathematical model is formed, relating u to x, where u is a vector of ui and x is a vector of the updates to the a-priori values of position, common-mode error, and absolute time of reception:
where n is the number of pseudoranges. The pseudoranges are expressed in units of length (e.g. meters).
The position updates, x, y, z, are expressed in units of length (e.g. meters) and the time updates tc, ts are in units of time (e.g. seconds)
An embodiment of a mathematical model relating these two vectors is a Taylor series, where the first term in the series is the first derivative of u with respect to x, the second term contains the second derivative, and so on. In one embodiment of the process, the invention uses a linearized model that keeps only the first derivative in the Taylor series. This gives the following equation relating u to x:
The particular values of ∂ρi/∂x, ∂ρi/∂y, and ∂ρi/∂z depend on the coordinate system used to describe the a-priori position. These terms in the first three columns of the matrix H are well known in the art, and further explanation is not required. The fourth column of the matrix is c, the speed of light, this part of the model is also standard in the art. The novel aspect of this invention requires the inclusion of the fifth column in the matrix. This fifth column exactly models the relationship between the unknown error in the a-priori estimate of absolute time, and the measured pseudoranges. Furthermore the terms in this column are the rate of change of the pseudoranges with respect to time and can be exactly calculated from the ephemeris data. Hence every term in the matrix H is known and, provided there are five or more pseudoranges available at the GPS receiver, the values of x can be calculated using linear algebra.
At step 220, the GPS receiver position is computed by adding the updates x,y,z, to the a-priori position, and the absolute time of reception is formed by adding the update ts to the a-priori time of reception. If the a-priori position and a-priori absolute time were close enough to the true position and true absolute time, then one pass through the process 200 will yield results to the required accuracy. However, if the first pass through the process 200 does not immediately converge on the required accuracy, then the result 222 is used to form a new a-priori time of reception estimate for step 202 and a new a-priori position estimate for step 206, and the process 200 is repeated until the result converges on the correct result (typically very few iterations are required because the linearization using the first order Taylor series is a very good mathematical description of the complete, non-linear, system, thanks to the fact that the satellite ranges are so much further from the earth than the error in the a-priori position).
It will be understood that the Taylor series is just one example of a mathematical model relating the unknown position and absolute time to the measured pseudoranges. The present invention is equally valid with other models, such as non-linear models, which can be solved through techniques such as iteratively fitting the unknown parameters until an acceptable solution is obtained.
If, as assumed above, the a-priori position and a-priori absolute time are within 100 km and 1 minute respectively, then the result 222 will be correct. However, if the a-priori position and time are not known within these limits, then the incorrect integers may be formed at step 210 and the incorrect result 222 may be obtained. In this case the a-posteriori residuals, formed at step 224, will be used, as described below with respect to FIG. 4, to detect this errant condition and then different a-priori values will be used.
FIG. 3 is a flowchart of an illustrative process 300 that resolves the sub-millisecond pseudorange integers (step 210 of FIG. 2). To simplify the exposition, this particular embodiment is assumed to have an a-priori position that is within 100 km of the true position of the GPS receiver, and an a-priori absolute time estimate that is within one minute of the true absolute time of reception at the GPS receiver. It will be understood that these simplifying assumptions, while often true in practice, are not a necessary part of the invention, and have been used here only to simplify the explanation of this embodiment of the invention. In the description relating to FIG. 4, FIG. 5, and FIG. 6, these simplifying assumptions are removed.
At step 308, the process 300 calculates the expected pseudoranges using ephemeris data (provided in step 208) for the satellites along with the a-priori absolute time of reception (provided in step 202) and the a-priori position (provided in step 206). As done throughout this specification, the term ephemeris is used to mean the satellite orbital parameters as well as the satellite clock parameters.
At step 310, a single satellite is chosen as a reference satellite. In the preferred embodiment the satellite with the highest elevation angle (from the a-priori position) is chosen as the reference, but it will be understood that it is not important which satellite is used as the reference. The expected pseudorange for the reference satellite is denoted r0 (path 312). The expected pseudoranges for the other satellites are denoted ri (path 314).
At step 318, an integer is assigned to the reference satellite. The integer must satisfy the equation:
where c is the speed of light, expressed in m/s, tc is the common mode error, and e0 is the error in the expected pseudorange introduced by the combined errors in the a-priori position and a-priori absolute time.
Those skilled in the art will understand that an arbitrary integer may be assigned, since in the following discussion it is seen that the common mode error will absorb any errors made in this integer, as long as exactly equal errors are made in all the other integers. The integer N0 is assigned according to the following equation:
At step 322, the integer millisecond values for the remaining satellites are calculated using the sub-millisecond pseudoranges 320 for all the satellites along with N0. Whatever value of N0 was chosen above implies an associated common mode error tc. The values of Ni are chosen to satisfy the following equation, which relates Ni, the measured sub-millisecond pseudorange (si), the expected pseudorange (ri), and the common mode error (tc).
where, ei is the error in the expected pseudorange introduced by the combined errors in the a-priori position and a-priori absolute time. In the preferred approach, the corresponding equation for N0 is subtracted from the above equation, this exactly cancels the term tc, since this term is common (by definition) for all satellites. This yields the following expression for Ni
The above equations represent one embodiment of a process to calculate the integers. It will be understood that any expression may be used to compute these integers, provided the relationship to tc is consistently maintained for all the integers.
In the above description the assumption was made that the a-priori position was within 100 km of the true position, and the a-priori absolute time was within 1 minute of the true time. For all GPS satellites, the maximum pseudorange rate is �800 m/s. Thus the maximum value of the error term ei will be 100 km+60s*0.8 km/s=148 km. This is less than half of one C/A code millisecond epoch (i.e., less than half of one integer millisecond) and the rounding operation used above will always yield the correct integers. In the disclosure with respect to FIG. 4, FIG. 5, FIG. 6, these two restrictions on a-priori position accuracy and a-priori time accuracy are removed.
If the a-priori position is not known to within 100 km, it will nonetheless be known to some finite accuracy limit. Similarly, if the a-priori absolute time is not known to within 1 minute it will be nonetheless be known to some finite accuracy limit. As described in the processes 200 and 300, any a-priori position and time estimate within the 100 km and 1 minute constraints will yield the correct integers, correct GPS receiver position, and correct absolute time. In an embodiment of the current invention, the space of all possible a-priori positions is divided into a 100 km�100 km lat-lon grid, with altitude assigned from a look-up table of topographical altitudes. Similarly the space of all possible a-priori absolute times is divided into 1-minute segments. This yields a set of all possible a-priori positions and times. The process 200 is used iteratively, with each of the possible a-priori position and time values from the set. When an a-priori position and time is found within 100 km and 1 minute of truth, then the a-posteriori residuals will be small, and the correct GPS receiver position and absolute time will be computed, as described above.
An embodiment of this process 400 is shown in FIG. 4. At step 402, all possible a-priori positions and residuals are formed into a set. In one embodiment the set is organized as a 100 km�100 km grid, with altitudes assigned from a lookup table of topographical heights, and with time segmented into 1-minute segments. This is a convenient representation because, as discussed above, the combination of a 100 km grid plus the maximum pseudorange rate times 1-minute gives a maximum possible estimated error of just less than half a millisecond of range, which is necessary for the integer resolution process 300 to select the correct integers. However it will be understood that any number of different methods may be used to organize the set of all possible a-priori values, including creating new elements of the set dynamically, based on the results obtained from previously used values.
At step 404, the process 400 selects one possible a-priori position and time combination. These values are used in the process 200. At step 406, the process 400 examines the a-posteriori residuals that are produced in step 224 of FIG. 2. If the correct GPS receiver position and absolute time have been calculated, then the magnitude of the residuals will be small (that is, of the same order as the pseudorange measurement errors—tens of meters). If the a-priori position and time were far enough away from the truth that the integer ambiguities were not correctly resolved, then the residuals will be large (that is, of the order of one millisecond epoch—many kilometers). If the residuals are large then the candidate a-priori position and time are incorrect and they are removed from the set of possibilities. The process 400 is iterated until the correct position and absolute time are calculated.
It will be understood by those skilled in the art that even if the absolute time is available at the GPS receiver, the process of integer ambiguity resolution has traditionally required an initial estimate of position close enough to the true position for the integers to be uniquely defined by said initial estimate. The current invention provides a novel means of computing the correct integers without requiring an accurate initial estimate of position.
FIGS. 5A and 5B respectively depict a grid 502 used to determine receiver position in an embodiment of the invention and the residual magnitudes 506 computed during the position calculation process 200. In this example, the a-priori position is assigned as an arbitrary guess, in the middle of North America. Then the process 200 is performed for each possible a-priori position (grid point 504), and the magnitude of the a-posteriori residuals is examined. As each wrong candidate is rejected another candidate (another grid point 504) is generated by searching outwards on a 1 degree�1 degree grid 502. (Note that this 1 degree�1 degree grid is a slightly different embodiment than the 100 km�100 km grid described earlier; both embodiments are guaranteed to give at least one a-priori position that will yield the correct integers, and hence the correct position and absolute time.) The a-priori position is completed by assigning an a-priori altitude from a lookup table of topographical heights. FIG. 5A shows the 1,663 wrong candidates on a grid 504 and FIG. 5B shows the corresponding residual magnitudes 506, each one of the order of an incorrect millisecond integer (i.e., many kilometers). Once the search reaches an a-priori position in the vicinity of the true position (in San Jose, Calif.) the mathematical model causes the correct result to "snap" into place, and the correct position and time are calculated. The a-priori position candidate number 1,664 (residual magnitude 508 and grid point 510) is approximately 175 km east of the true position, which, in this example is close enough for the position and time solution to "snap" into place. The correct solution yields a residual that is approximately 30 meters, which is from one thousand to ten thousand times smaller than the incorrect residuals.
The large difference between "small" residuals (tens of meters) and "large" residuals (tens to hundreds of kilometers) makes this embodiment work very well in practice. However, it will be understood that other methods may be used to test the quality of the result, including comparing the calculated position and absolute time to a position and time obtained through some other means—such as the location of the radio tower used in a wireless-aided system. It will also be appreciated that in order to have non-zero residuals, it is necessary to have more independent observations than unknowns. In the embodiments described thus far, there have been five unknown parameters: three coordinates of position, common mode error, and absolute time. Thus at least six independent measurements are required to have non-zero residuals. If six GPS satellites can be observed, then the six measurements can be obtained from them. If there are not six satellites observable then there are several steps that can be taken, many of which are standard in the art. The number of measurements may be increased by including measurements from other sources (such as range measurements based on time-of-arrival from a wireless system, or angle-of-arrival measurements measured in a wireless system, or any other independent measurement that can be obtained).
The number of observables can also be increased by including, as "pseudo-measurements", known constraints on position, for example known or approximately known altitude can be introduced into the mathematical model as a pseudo-measurement. In the embodiment specified above, where the mathematical model is represented by the equation u=Hx, a pseudo-measurement for known altitude may be created by first specifying the a-priori position in coordinates of latitude, longitude, and altitude, then by setting the a-priori altitude to the known altitude, then by adding a new line to the matrix equation:
This approach effectively adds another measurement or observable to the mathematical model. This approach is standard in the art, and it is understood that it applies to any constraints that may be useful in solving for the unknown parameters.
Another approach is to reduce the number of unknown parameters. This may be performed by removing known, or approximately known parameters. The most commonly known parameter is altitude, and it can be removed from the mathematical model. Similarly the common mode error may be calibrated (for example, if the invention is implemented in a system with access to a stable oscillator) and removed from the mathematical model.
It will be appreciated that many combinations of the disclosed techniques may be applied to compute unknown values, including unknown absolute time.
For example, using the techniques of this invention, one can compute the time parameters alone, without computing the position. This is done, in the preferred embodiment, by fixing the position in the mathematical model to the a-priori position, and computing the remaining two unknown parameters: common mode error and absolute time.
FIG. 6. is a graphical representation 600 of the residuals magnitudes (axis 602) associated with the different a-priori times (axis 604) that were attempted in an example embodiment of the invention. In this particular example, a range of possible times, each one-minute apart, is attempted for each of the grid points shown in FIG. 5. The first a-priori absolute time was chosen by guessing a time that turns out to be approximately two-and-a-half hours later than the true absolute time of reception. When the process 400 applies an a-priori position approximately 175 km away from the true position, and an a-priori time within one minute of the true absolute time, the mathematical model calculates the correct position and time, as shown in FIG. 5. In general, the mathematical model will calculate the correct position and time as soon as the a-priori position and time are close enough to cause process 300 to calculate the correct integers. As discussed, the preferred embodiment is guaranteed to find at least one such a-priori position and time, by creating an appropriate grid, and appropriately spaced time intervals.
In the embodiment described above, the invention has computed absolute position of a satellite signal receiver and absolute time of reception of satellite signals using pseudoranges and ephemeris. It may be desirable, however, to compute absolute position of a satellite signal receiver without ever computing absolute time of reception for the satellite signals. Thus, the present invention advantageously utilizes GPS measurements to determine receiver position without knowing or calculating precise GPS time-of-day (TOD).
To best explain the second embodiment of the present invention, it is necessary to understand why precise GPS TOD is needed in prior art GPS position calculations. GPS receivers compute position by measuring their distance from several satellites, by receiving a radio signal and measuring the delay between transmission and reception of said signal. Then, using satellite orbit data and precise TOD, the satellite positions can be determined at the moment that the signal was transmitted. Finally, using the measured distance from the known satellite positions, the receiver position is computed. Thus, in a prior art GPS receiver, if precise TOD is not known, then the precise satellite positions cannot be determined. The error in the position of each satellite will result in an error in the computed receiver position. This error can be very large, even with a small imprecision in the TOD. The GPS satellites move, relative to an observer on the earth, at up to 800 meters per second. Thus an error of just one second in precise time-of-day will result in a position error of 800 meters. This is why prior art GPS receivers have required precise time-of-day.
In accordance with the present invention, the mathematical model formed in step 216 of FIG. 2 is transformed into an equivalent model in which the absolute time variable is eliminated. In this manner, the present invention obviates the need to determine precise TOD. More specifically, techniques for eliminating one unknown variable in a multivariable set of equations before computing the other variables are well known in the art. An embodiment of the invention employing one such technique can be understood by studying the Taylor series description of the mathematical model formed in step 216:
The a-priori pseudorange residuals ui can be combined to transform the matrix H into sub-matrices that decouple the unknown absolute time variable ts from the other unknowns. Specifically, for each a-priori pseudorange residual ui where i is greater than 1, a new a-priori pseudorange vi can be formed as follows:
Note that this is equivalent to pre-multiplying the equation u=Hx by the matrix:
The above transformation results in a new set of equations:
where the variable ts has been decoupled, Hi,j are the coefficients of the H matrix, and Gi,j are the coefficients resulting from the above pre-multiplication. As such, the equations relating the new a-priori pseudoranges v2 through vn to the unknown variables x, y, x, and tc can be separated. Provided there are five or more pseudoranges available at the GPS receiver, the values of the remaining unknown variables can be calculated using linear algebra.
There are many similar well-known methods to eliminate unknown variables from a multivariable equation. Using these techniques, the present invention can solve for any subset of the unknown position and time variables. By solving only a subset of unknown position and time variables, the present invention reduces computation complexity and allows for lack of knowledge of a particular variable, for example, absolute time.
Although the present invention has been described as using ephemeris data for obtaining satellite orbits and clock parameters, equivalent descriptions of such parameters can also be used. There are many equivalent descriptions of the satellite orbits that can be used, including descriptions of the orbits as viewed from the GPS receiver. The satellite ephemeris could be replaced by a model of the expected pseudoranges, a model of the expected geometric ranges and a clock model, or by another combination of models that describe the satellite orbits and/or clock parameters. Since all these models serve similar purposes, the term "ephemeris" as used hereinabove means satellite orbital parameters, satellite clock parameters, or like type functionally equivalent data.
Although the methods and apparatus of the present invention have been described with reference to GPS satellites, it will be appreciated that the teachings are equally applicable to positioning systems which utilize pseudolites or a combination of satellites and pseudolites. Pseudolites are ground based transmitters that broadcast a PN code (similar to the GPS signal) which may be modulated on an L-band carrier signal, generally synchronized with GPS time. The term "satellite", as used herein, is intended to include pseudolites or equivalents of pseudolites, and the term "GPS signals", as used herein, is intended to include GPS-like signals from pseudolites or equivalents of pseudolites.
In the preceding discussion the invention has been described with reference to application upon the United States Global Positioning System (GPS). It should be evident, however, that these methods are equally applicable to similar satellite systems, and in particular, the Russian Glonass system and the European Galileo system. The term "GPS" used herein includes such alternative satellite positioning systems, including the Russian Glonass system and the European Galileo system.
Although various embodiments that incorporate the teachings of the present invention have been shown and described in detail herein, those skilled in the art can readily devise many other varied embodiments that still incorporate these teachings.
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text:
Texas on the Potomac
Washington news with a Texas accent
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Storify: Tweets get funny on Election Day
The Big Vote brings out the comedian in a whole lot of people. It definitely adds levity to the serious proceedings. Enjoy some of the funniest and most clever examples. [Read More]
The Week Ahead: Legislative work is over until November
House Republican leaders have made no secret of their plan to use the balance of the session before Election Day to focus on measures that draw bright lines of difference with the Democratic Senate and President Barack Obama. [Read More]

subset: commoncrawl


text:
System object: comm.SphereDecoder
Package: comm
SphereDecoder object with same
property values
C = clone(H)
C = clone(H) creates a
SphereDecoder object
with the same property values as
H. The
clone method
creates a new unlocked object with uninitialized states.
The clone method creates an instance of an object. The property values, but not internal states, are copied into the new instance of the object.


text:
All steel 2-door Sedan in Red ... Beige tweed & leather interior ... '49 Merc Flathead V-8 ... Vintage A/C ... Top shelf build... More
1996 Bentley Azure Convertible like New only 38,000 Miles form New. Green with Tan Leather interior V8 Turbo with Automatic. Fully Loaded upgraded sound... More
The Buick Grand National resides today in the hearts of many, and in the hands of a select few. A surge in the following... More
The Classic Car Gallery is proud offer this stunning Rolls-Royce Corniche II is finished in BLACK with a Biscuit Tan Connolly hide leather interior... More
1971 Chevrolet Chevelle SS 454, with a factory build sheet. Matching numbers engine. Built in the Van Nuys plant in California and then shipped... More
1958 Chevrolet Corvette: 290 HP 283 CI V8 Fuel Injection - Silver Blue Exterior / Inca Silver Coves with Blue Gray Interior and matching... More
Amazing 1937 Ford Roadster steel car show winner. This car was built by Norm Francis with interior by Ron Mangus and designed by the... More
Just in! Call or visit our website for more information.... More
Masons Black Exterior Black Interior 100 Made for US/350 for World Unusually Low Mileage This 2009 Bentley Brooklands Mulliner Coupe is very unique. It has diamond stitched upholstery... More
For Sale, 1953 Canadian Built Chevrolet 150/121 model.This car is like a better than new 1953 Chevrolet.It is 100 % restored. 12 volt conversion. The exterior... More
1939 Plymouth P8 - Four year frame off restoration by Atlanta Auto Restoration, Hampton GA ALL Steel Body 360 Mopar engine built by Carolina Machine Engine;... More
1966 Ford GT 40 Mark 1 Manufactured by CAV , Chassis #107. Le Mans Blue with Wimbledon White stripes.[Built in 2006 and registered in... More
Well sorted, thoroughly engineered, professionally built car that is near perfect. Small block 383 CID / 400 HP, aluminum heads, roller cam, Demon Six... More
V12 6.3L 740HP, Dual Clutch Sequential Transmission ____ Included Genuine Maintenance until March 2022 and Full Ferrari Warranty until March 2018 ____ OVER 80K$... More
This 1932 Cadillac 370B Convertible Coupe is an excellent example of Cadillac's long reputation for elegance and luxury. It has the V-12 motor designed... More
Chassis # ZFFKW64A590165554 One-Owner & Only 4,400 Miles From New Well Documented Including Original Window Sticker Clean Carfax With All Manuals, Tools, and VIP Build Documents Ferrari needs... More
2005 Ford Thunderbird Premium, Only 2,090 actual miles. Never driven in rain. Never any paintwork or damage. Looks, runs, smells like a new car. ... More
Take a look at this GORGEOUS - LOW ORIGINAL MILEAGE - ONE OWNER SINCE NEW - MOSTLY ALL ORIGINAL SURVIVOR !! - 1979 Ford... More
REDUCED TO SELL 1935 2 Door sedan Car is originally from Indiana and has been owned by collector since 1974 and has been restored to original... More
VIN: 3GPE10591 condition: mint cylinders: 6 cylinders drive: rwd fuel: gas odometer: 19,893 paint color: blue size: full-size title status: clean transmission: manual type: pickup Wheels of Time is predominantly a classic vehicle restoration shop... More
Highly original car that just came out of a collection in Nashville. Fully serviced and ready to be driven and enjoyed daily. Brand new... More
1966 Lincoln Continental Convertible, This is a exceptionally original, clean car. Still smells new inside. loaded with most options available in the 1966. Everything... More
Of all the marques that lined up for the 1923 Le Mans Grand Prix, only one survives–Bentley. In fact, throughout the 1920s, no other car... More
Then and now, thousands of eyes were / are focused on Chevrolet Trucks because these trucks were the most powerful, finest performing, best looking... More
1969 Ford Mustang Boss 302, Engine The original numbers matching VIN stamped C8FE block with main caps is included and mounted on a rolling stand… it... More
Beautiful and Very Rare (only 1999 of these made in 1955) Ford Crown Victoria Sunliner "Glasstop". A Real Show Stopper. Original 272 Ford V-8... More
1960 Chevrolet Corvette Roadster, Frame-off restoration to NCRS specs. Upgraded with Tremec 5-speed, stereo with CD and IPod, new radial whitewalls, stainless exhaust, Wilwood... More
1930 FORD ROADSTER PICKUP, BROOKVILLE CHASSIS AND ALL STEEL EXTENDED CAB BODY. 302 FORD MOTOR, C4 AUTOMATIC TRANSMISSION, DUAL FUEL TANKS, LOKAR SHIFTER, REAL... More
Wonderful 1958 Chrysler Imperial Crown Convertible. Believed to be one of less than 20 existing. Frame off restored in 2013. 392 Hemi 345hp, Carter... More
If you are looking for a nice AMG E55 driver, then this is not the car for you. If you would like one of... More


text:
Peter A. Jensen
I have been with Microsoft since 2002, but I have been with Dynamics even longer, starting out with a Dynamics NAV partner in 1992. I currently lead the Partner Programs team in the US Dynamics organization and look forward to keeping in touch with the US Dynamics Partner Community on this blog.
Now that we are a couple of weeks into the start of FY13, the Microsoft Dynamics Operations team provides this important information regarding a change to month-end close timing.
The Microsoft Business Solutions (MBS) business has now aligned to the greater Microsoft/Volume Licensing (VL) business close dates and will now end the month processing at 4:00PM local Regional Operations Center (ROC) time on the day of the close. This means that MBS will no longer close at midnight local time the day prior to the Microsoft/VL close.
Through great efforts across multiple teams, MBS is now able to support the aligned close date by overcoming previous challenges across the billing systems. This new alignment simplifies the month end close for partners by providing a consistent close timing schedule across Microsoft with better alignment of the end of processing times across lines of business.
Given the impact of this change, please become familiar with the new FY13 close dates and cut-off timing to ensure smooth month-end and quarter-end close experiences for your organization.
The Microsoft Dynamics worldwide partner marketing team has created a new resource offering practical, simple and customized marketing support for partners. Earlier this month on the Marketing Dynamics blog, Fallon Emery shared details regarding the Microsoft Dynamics Partner Marketing & Lead Generation Toolkit.
The Partner Marketing & Lead Generation Toolkit offers practical guidance for Microsoft Dynamics partners on how to plan, invest, execute and measure more effective marketing. Focusing on marketing strategy, the guide includes helpful tips, best practices, exercises and links to an extensive selection of Microsoft training and resources.
Learn more about the toolkit by visiting the Marketing Dynamics blog.
On the heels of two successful Technical Conferences for Microsoft Dynamics AX, we are expanding and repeating it as we approach the launch of Microsoft Dynamics AX 2012 R2.
Make key business connections with the people that build Microsoft Dynamics AX, along with their colleagues from SharePoint, Office, BizTalk, Visual Studio and other areas of Microsoft. Hear new, practical and technical content, as well as best practices, delivered by Microsoft leaders and technology experts. Stay up-to-date around Microsoft Dynamics AX 2012 R2 and learn more about the simplicity in deployments, master data management and contextual business intelligence, along with new world class capabilities within Financials. Learn from and get inspired by your colleagues from around the world.
Meydenbauer Convention Center, Bellevue, Washington October 22-25, 2012
Registration will open in late July.
Sign-up for email alerts today and be one of the first people to receive event updates on registration opening, agenda & content updates, and more!
Visit PartnerSource for more information.
The clock is ticking as the early bird discount for the Microsoft Dynamics GP Technical Airlift is quickly approaching. Haven't registered yet? Michelle Spitzer, Director of Marketing for Dynamic Communities, Inc., shares this update to provide you with the most compelling reasons to attend.
Register for the Microsoft Dynamics GP Technical Airlift before Tuesday, July 31 to save $100 on your registration. This year's event is focused on delivering advanced technical skills around Microsoft Dynamics GP 2013 for implementation professionals, consultants, developers and technical sales engineers. With about 30 sessions scheduled for the 3-day event, it is one of your best opportunities to gain knowledge and training on the upcoming release of Microsoft Dynamics GP 2013.
Microsoft Dynamics GP Technical Airlift, Hosted by GPPC September 12-14, 2012 – Microsoft Campus – Fargo, ND Register Now!
Microsoft Dynamics GP Technical Airlift, Hosted by GPPC September 12-14, 2012 – Microsoft Campus – Fargo, ND Register Now!
Breakout Sessions
The breakout sessions are designed to dig deep into advanced technical skills around Microsoft Dynamics GP 2013 for both consultants and developers. With a focus on workflow, business intelligence, SQL Reporting Services, and planning for security and compliance, the event will include sessions like:
Click to see the complete session schedule and event agenda.
Keynote Sessions
The Airlift will kick off on Wednesday with an exclusive look at Microsoft Dynamics GP 2013, provided by a high-powered line-up of Dynamics GP product insiders. Errol Schoenfish, Director of Product Management for Microsoft Dynamics GP, will set the stage for the week and, more importantly, what the release of Dynamics GP 2013 will mean to you and your customers. Kevin Racer, the program manager responsible for many of the aspects of the Microsoft Dynamics GP 2013 web client, will provide a comprehensive overview of the new web client. He'll walk through the architecture, deployment model and UI changes that make up the web client. Daryl Anderson will join Kevin to dive into deploying Dynamics GP 2013, including on-premise, the web client, mixed mode deployments, and everything in between.
Thursday's keynote will focus on Windows 8, which represents one of the largest opportunities for application developers for the 21st century. Mark Hindsbo, Vice President of Microsoft's Developer & Platform Evangelism Group in the US, will give a sneak-peak into Windows 8 and share insight about how you can take advantage of this new opportunity.
Learn more about the event and sign up at http://www.GPPCTechnicalAirlift.com.
Our US Microsoft Dynamics marketing team has these very important announcements to enhance your marketing efforts as we enter the new Microsoft fiscal year.
Kick off FY13 by checking out the new, improved Marketing Services Bureau (MSB) on PartnerSource! The MSB professional agencies have been carefully selected for their experience and effectiveness. Whether you need a list, consulting services, an outsourced marketing director or a social media solution, MSB can help fill your marketing gaps, accelerate your path to new leads and provide the marketing services you need.
In addition to the great MSB marketing services, we're starting FY13 with three special offers from N3 - Niche Cubed, Nurture Marketing and The Partner Marketing Group. These offers will help you effectively build an active sales pipeline, review and assess your current marketing and plans, and address a wide range of content development. But hurry: Some of the offers are time-limited. Visit the MSB Special Offers site on PartnerSource and return often for the latest deals from Microsoft Dynamics-savvy marketing vendors!
The details of Perpetual Licensing are now available on PartnerSource, including a readiness video, pricing details and the licensing guide.
For more information register for the live Ask the Expert session on Microsoft Dynamics ERP Volume Pricing on Monday, July 23, 2012 at 11:00AM PT.
The results are in! Huge and appreciative congratulations to our FY12 Inner Circle and President's Club partners for a very successful year.
The Microsoft Dynamics Inner Circle represents an elite group of the most strategic Microsoft Dynamics partners from around the globe, with sales achievements that rank them in the highest echelon of the Microsoft Dynamics global network of partners. These partners are recognized for their exceptional overall company performance in delivering valuable solutions to Microsoft Dynamics customers.
Microsoft Dynamics President's Club honors high-performing Microsoft Dynamics partners with a commitment to customers reflected in their business success and growth.
A list of the 2012 Microsoft Dynamics Inner Circle award winners can be found here.
A list of the 2012 Microsoft Dynamics President's Club award winners can be found here.
Again, congratulations, and enjoy this well-deserved honor!
At the Microsoft Worldwide Partner Conference (WPC) 2012 in Toronto today, Microsoft honored the strongest-performing Microsoft Dynamics partners for demonstrating significant customer impact by developing and delivering innovation solutions that help customers drive their businesses forward.
At WPC 2012, 10 Microsoft Dynamics partners were recognized with the Microsoft WPC 2012 Awards. The Microsoft WPC 2012 award recipients are as follows:
For a complete list of winners and finalists, please review this previous blog post.
Out of thousands of partners, Microsoft also honored 13 resellers with the 2012 Microsoft Dynamics Regional Reseller of the Year award, and nine independent software vendors (ISVs) were awarded the 2012 Microsoft Dynamics Regional ISV of the Year award. In addition, select top performers were honored from the Microsoft Dynamics channel, including Tribridge Holdings, LLC, named the Microsoft Dynamics Outstanding Reseller of the Year, and AXtension bv, named the Microsoft Dynamics Outstanding ISV of the Year.
In the United States, mcaConnect, LLC was named Microsoft Dynamics Reseller of the Year, and TDCI Inc. took the Microsoft Dynamics ISV of the Year honors. Finalists for US Reseller were Armanino McKenna, LLP and Zero2Ten, Inc. Finalists for US ISV were Blue Horseshoe Solutions, Inc and ExactTarget, Inc.
For a detailed list of Regional winners from across the globe, please visit the Microsoft News Center.
Congratulations to all partners!!!
This a fabulous new video from the Microsoft Dynamics marketing team. Enjoy!
We have exciting Microsoft Dynamics news coming out of WPC 2012 today.
TORONTO — July 10, 2012 — They are companies that support the most complex manufacturing, distribution and services industries in the world today. They help customers build submarines, manage large automotive dealerships and optimize sales effectiveness.
Today in Toronto, Microsoft Business Solutions President Kirill Tatarinov discussed how enterprise partners that operate in highly specialized, vertical markets across the world are increasingly turning to software that has historically been seen as a midmarket offering — Microsoft Dynamics.
To make his point, Tatarinov pointed to three global ISVs currently building solutions on Microsoft Dynamics platforms to serve large, complex organizations in different ways.
To learn more, view the complete press release on the Microsoft News Center.


text:
No. 80:17–21). The irritation mechanism of action leads to pulmonary edema and potential lethality. An n of 2 is also relevant to animal lethality studies.
Data adequacy: The database for chlorine is extensive with multiple studies of lethality conducted at several exposure durations and involving several species. Studies with multiple dosing regimens showed a clear dose-response relationship. Longer-term studies that support the safety of the values were also available. Tissue and organ pathology indicated that the toxic mechanism was the same across species.


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The time for mourning has come and gone. Before we can rebuild, we need to understand what failed in the first place.
First of all, we did not have the wrong guy. All the conservatives who fought for a non-Romney in the primaries, and then rallied behind Romney and found themselves quite pleased with him when he pulled ahead, have once again pulled out their knives. If they think Santorum or Cain, Gingrich or Perry would have done better, they are living in a bubble with sparkly rainbows and unicorns dancing in the glen. Since I supported Romney in the primaries, I recognize I have a vested interest in defending that decision. But Romney did not lose because he wasn't conservative enough. Mitt was the best candidate we've had since Reagan. Certainly better than Dole, McCain and Bush the Elder, and in my opinion he was better than Bush the Younger. Bush would not have beat an incumbent Obama. If Mitt had been able to make the conservative case as powerfully as Reagan, would it have been different? I'm not sure. Of course, everyone is a brilliant strategist when they're not the ones running the campaign, and they're practically omniscient after the results are in. No question, there were things that could have been done differently. No candidate is perfect; no campaign is perfect; but Romney was a strong candidate with a strong campaign. Of all the Republican politicians who realistically might have run, Jeb Bush is the only one who might have stood a better shot.
It was never going to be a cakewalk. One of the prevailing assumptions of the anyone-but-Romney crowd in the primaries was that we could run Gary Coleman — yes, even though he's dead — and beat Obama in this economy. These were the same people who could not believe that Romney was not wiping the floor with the President. They were living in an alternate reality. They believed the rest of the country viewed Obama as a feckless failure, just like they did. But the truth is, most of the country still likes Obama personally, and views his performance in the presidency as a middling performance at worst.
Obama's approval numbers were low, but (as I said they would) they rose once he began to campaign and tout his "accomplishments." An 8 percent unemployment rate is bad, but it doesn't look so bad when it's dropped from 10 percent, most of the electorate still blames Bush, and the media is eager to make it look like significant progress. Plus, the advantages of incumbency are massive. Obama rallied his base with a string of executive orders and with his public turnabout on gay marriage. He purchased the favor of the young through his college loan reform, and locked down the single female vote with the Lily Ledbetter bill and the Hispanic vote with his immigrant reform by executive fiat. The successful mission against Osama bin Laden effectively muted any criticism on foreign affairs. Benghazi gave him the opportunity to repeat numerous times how decisively he had purportedly acted (the alternative, Obama-left-them-to-die narrative coming from the Right was always too plainly self-serving and never caught on outside the conservative press) in directing the military and intelligence to respond, and Sandy gave him the opportunity to tour the disaster scene in his bomber jacket with one of Romney's most important surrogates slobbering on his arm. Obama is a formidable campaigner, performed quite well in the second and third debates, and had a massive advantage in GOTV and new media. Naturally he had the mainstream media completely in his pocket, steadfast support from unions, and academic and entertainment establishments making the case to the youth vote.
Finally, let's not blame it on Sandy. Yes, she was a factor. The exit polls make that clear. Clearly the Obama campaign saw the golden opportunity and rushed to put him on the scene in his commander-in-chief jacket. But Republicans lost seats in the House and the Senate and lost control of some state houses — and this can't be blamed on Sandy. The exit polls also make clear that Republicans have some clear problems appealing to specific demographics, and if we blame Sandy (or the strength of the Obama ground game) for the loss we rob ourselves of the opportunity to learn some very important lessons. Here, I think, are some of the things we need to learn:
- The Republican brand is terrifically damaged, especially with minorities, the young, single women, and the religiously unaffiliated. It's tempting to blame this on Bush, but I don't think that's quite right. For one thing, the list of Republican malfeasants is long, from Newt to Mourdock. For another, I don't think Bush's actions have harmed the brand nearly as much as the failure of the Bush-ites to defend them. Bush has disappeared since he left office, and he's so radioactive no one wants to defend him. It's ludicrous that Bush alone takes the blame for the financial crash of 2008 — and yet that's the view that has taken hold in the absence of any argument to the contrary. I don't think it's an exaggeration to say that Obama held onto the presidency because America still blames Bush for the bad economy, and people still blame Bush because we have failed to press a better and more accurate narrative of the financial collapse out into the mainstream.
- The Evangelical Vote is still united — but evangelicals are both a blessing and a curse to the Republican party. Everyone is talking about the death of the Christian Right, but I don't see it quite that way. 8 of 10 evangelicals voted for Romney. Ralph Reed's Faith and Freedom Coalition was one of the most powerful forces the GOP had this year. The evangelical vote for Romney was stronger than it was for the born-again GW Bush. It's just not enough. Also, evangelicals (I'm trying to be objective here) damage the brand through Akin- and Mourdock-like boneheadedness and make it harder for Republicans to reach out to youth, single women, and the nones.
- Conservative media too is a blessing and a curse. After watching this happen to liberals for decades, this time it was conservatives who fell prey to the echo chamber effect. We believed our own hype. Fox News and talk radio fought to bring the Mexican gun-running story, Benghazi-gate, and any number of other mistakes and misstatements into the conversation, but those things never penetrated the mainstream media. They're just preaching to the choir — and the choir needs to get out a little more. The simple fact is, conservatives made the mistake of assuming that the rest of the country too viewed Obama as a feckless failure. But the rest of the country by and large likes Obama and thinks he has done, at worst, a middling job.
- Conservatives are losing the culture. State propositions and referenda, along with the direction of the youth vote and the growing Hispanic vote, suggest that conservatives (and the evangelicals who stand at their base) are losing the struggle for American culture on issues like gay marriage, immigration and the role of government. The Obama campaign framed this election as a decision between "you're on your own" or "we're all in this together." It's a fantastically self-serving way of framing the decision, of course, but it resonates because conservatives have not provided a powerful moral argument for their vision of economy and community. The Republican party is viewed as the harbor of bigotry and greed. As long as that's the image, it will not be an effective party.
Christians, of course, have a higher hope, but I'm simply looking now at the human level of politics. The Republican party's best hope, in a nutshell, is for grassroots cultural renewal and for drawing on the strengths of its governors, putting forward voices who are innovative and accomplished, diverse and winsome, men and women who represent the Republican vision of social mobility and who can make the moral case for conservative priorities. More on this soon.


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When we saw the first trailer for Caitlyn Jenner's upcoming do Read More »
After beating No. 1 ranked Germany in a 2-0 victory, the United States Women's National Soccer team is officially in the 2015 Women's Word Cup Final. Read More »
Fifty Girl Scouts had the experience of a lifetime on Tuesday night. Read More »
Betsey Johnson's punky, funky, completely spunky style translates perfectly to the dance world, as evidenced by her brand-new collection for dance-wear giant Capezio. Read More »
Natasha Case had a nightmare just the other night — her first in years. Read More »
When you're sweating in the gym or running the track all alone, it can be easy to lose sight of why you're really there. Sure, we all work out to be fit (and maybe even to look a certain way), but there's so much more to it. Read More »
If you haven't seen Magic Mike XXL yet, close your browser, hydrate, and go directly to your local movie theater. This piece contains spoilers. No, seriously, I am going to ruin everything. Read More »
When they take the field at the FIFA Women's World Cup in Canada starting June 6, the U.S. Read More »
In college, Alexandra Johnson was just like most of her peers—she had a love of learning and an even stronger love of fashion. So when it came time to nail down a career path, she simply married her two loves. Read More »
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Review: Nike Zoom Pegasus 31
—01. White/Volt/Black.
I've been running exclusively in the Nike Flyknit Racer for the past year and a half. When it comes to road running, I've never found a better shoe and I still don't really expect to. However, they are extremely minimal and sometimes I feel like a more stable, cushioned ride would be nice, so I decided to try out the latest edition of the Zoom Pegasus. I thought it was one of the best versions of the shoe recently and I was pleasantly surprised. Even with the added bulk, they felt lightweight, and not overly 'soft' – something the Lunar 1 and 2 have grown to feel after running on the Racer. The silhouette looks and feels well-balanced on foot, and I felt quite quick in my stride. While I'm still a big fan of the Lunar sole, I think that the Zoom is a better option for anything over 10km.