Data boundary aware base station assisted position location

• US 7,949,351 B2
• Filed: 11/24/2008
• Issued: 05/24/2011
• Est. Priority Date: 09/09/1998
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Zou, Qiuzhen, Kang, Inyup, Sih, Gilbert C.
• Primary Examiner(s): Lee; John
• Application Number:
  US12/277,104
• Publication Number:
  US 20090082036A1
• Time in Patent Office: 911 Days
• Field of Search: 455/456.1, 455/456.6, 455/67.16, 455/12.1, 455/13.1, 455/427, 455/414.2, 455/430, 455/517, 455/9, 342/418, 342/378, 342/357.62, 342/357.59
• US Class Current: 455/456.6
• CPC Class Codes: G01S 19/235 Calibration of receiver components
• CPC Class Codes: G01S 19/246 involving long acquisition integration times, extended snapshots of signals or methods specifically directed towards weak signal acquisition
• CPC Class Codes: G01S 19/254 relating to Doppler shift of satellite signals
• CPC Class Codes: G01S 19/258 relating to the satellite constellation, e.g. almanac, ephemeris data, lists of satellites in view
• CPC Class Codes: G01S 19/30 code related G01S19/246 takes precedence
• CPC Class Codes: G01S 5/0036 of measured values, i.e. measurement on mobile and position calculation on base station

Abstract

The present invention is a novel and improved method and apparatus for performing position location in wireless communications system. One embodiment of the invention comprises a method for performing position location on a subscriber unit in a terrestrial wireless telephone system using a set of satellites each transmitting a signal, the terrestrial wireless telephone system having base stations, including the steps of transmitting an aiding message from the base station to the subscriber unit, said aiding message containing information regarding a data boundary for each signal from the set of satellites, applying correlation codes to each signal yielding corresponding correlation data and accumulating said correlation data over an first interval preceding a corresponding data boundary yielding a first accumulation result, and a second interval following said corresponding data boundary yielding a second accumulation result.

Claims

1. A method comprising;

at a satellite positioning receiver, receiving a satellite signal including a navigation message, wherein the navigation message includes a plurality of navigation data bits, with a data boundary between adjacent navigation data bits;

accessing information indicative of the position of data boundaries in the navigation message included in the satellite signal;

coherently integrating a first signal sample of the satellite signal to obtain a first coherent integration result, wherein the first signal sample includes a first navigation bit prior and adjacent to a particular data boundary in the navigation message and a second navigation bit subsequent and adjacent to the particular data boundary;

coherently integrating a second different signal sample of the satellite signal to obtain a second coherent integration result; and

non-coherently combining at least the first coherent integration result and the second coherent integration result to obtain an integration result for the satellite signal.

2. The method of claim 1, further comprising:

generating information indicative of the position of the satellite positioning receiver using the integration result for the satellite signal.

3. The method of claim 2, further comprising:

at the satellite positioning receiver, receiving a different satellite signal including a different navigation message;

accessing information indicative of the position of data boundaries in the different navigation message included in the different satellite signal, wherein the position of the data boundaries in the different navigation message included in the different satellite signal is offset from the position of the data boundaries in the navigation message included in the satellite signal;

coherently integrating a plurality of signal samples of the different satellite signal to obtain an associated plurality of coherent integration results;

non-coherently integrating the plurality of coherent integration results to obtain an integration result for the different satellite signal; and

wherein the information indicative of the position of the satellite positioning receiver is further generated using the integration result for the different satellite signal.

4. The method of claim 1, wherein if a value of the second navigation bit of the first signal sample is unknown, coherently integrating the first signal sample comprises accumulating a portion of the first signal sample corresponding to the first navigation bit as a first accumulation and accumulating a portion of the first signal sample corresponding to the second navigation bit as a second accumulation and determining the greater of a sum of the first accumulation and the second accumulation and a different of the first accumulation and the second accumulation.

5. The method of claim 1, wherein the satellite positioning receiver is included in a mobile device, and wherein accessing information indicative of the position of data boundaries in the navigation message included in the satellite signal comprises accessing aiding information received at the mobile device.

6. The method of claim 1, wherein the satellite positioning receiver is included in a mobile device, and wherein accessing information indicative of the position of data boundaries in the navigation message included in the satellite signal comprises processing the satellite signal at the mobile device to determine the information indicative of the position of data boundaries in the navigation message.

7. A mobile device comprising:

means for receiving a satellite signal including a navigation message, wherein the navigation message includes a plurality of navigation data bits, with a data boundary between adjacent navigation data bits;

means for accessing information indicative of the position of data boundaries in the navigation message included in the satellite signal;

means for coherently integrating a first signal sample of the satellite signal to obtain a first coherent integration result, wherein the first signal sample includes a first navigation bit prior and adjacent to a particular data boundary in the navigation message and a second navigation bit subsequent and adjacent to the particular data boundary and for coherently integrating a second different signal sample of the satellite signal to obtain a second coherent integration result; and

means for non-coherently combining at least the first coherent integration result and the second coherent integration result to obtain an integration result for the satellite signal.

8. The mobile device of claim 7, further comprising:

means for generating information indicative of the position of the mobile device using the integration result for the satellite signal.

9. An article comprising non-transitory machine readable media storing instructions that when executed by a processor cause one or more machines perform operations comprising:

accessing information indicative of a navigation message retrieved from a satellite signal received at a satellite positioning receiver, wherein the navigation message includes a plurality of navigation data bits, with a data boundary between adjacent navigation data bits;

storing information indicative of the position of data boundaries in the navigation message included in the satellite signal;

accessing an integration result for the satellite signal, wherein the integration result is based on non-coherent integration of a first coherent integration result and a second coherent integration result, wherein the first coherent integration result is generated by coherent integration of a first signal sample of the satellite, wherein the first signal sample includes a first navigation bit prior and adjacent to a particular data boundary in the navigation message and a second navigation hit subsequent and adjacent to the particular data boundary;

accessing integration results for at least two additional satellite signals, and

generating position information indicative of a position of the satellite positioning receiver using at the integration result for the satellite signal and the integration results for the at least two additional satellite signals.

10. A mobile device comprising:

a satellite receiver configured to receive positioning signals, wherein the positioning signals include a first satellite signal from a first satellite, the first satellite signal including a navigation message with a plurality of navigation data bits, with data boundaries between adjacent navigation data bits;

memory to store information indicative of positions of the data boundaries in the navigation message;

a coherent integrator configured to perform coherent integration of portions of the received positioning signals and generate coherent integration results, wherein the mobile device is configured to coherently integrate a first signal sample of the first satellite signal including a data boundary between a first navigation bit and a second navigation bit;

a non-coherent integrator configured to perform non-coherent integration of generated coherent integration results and to generate an integration result for the satellite signal therefrom; and

a processor to determine information indicative of the position of the satellite receiver using the integration result for the satellite signal.

11. The mobile device of claim 10, wherein the information indicative of the position of the satellite receiver comprises a pseudorange between the satellite receiver and the first satellite.

12. The mobile device of claim 10, wherein the information indicative of the position of the satellite receiver comprises a location of the satellite receiver.