Method and apparatus for processing satellite positioning system signals

• US 9,020,756 B2
• Filed: 05/04/2004
• Issued: 04/28/2015
• Est. Priority Date: 04/23/1999
• Status: Expired due to Fees

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Global Locate Incorporated (Broadcom, Inc.)
• Inventors: Abraham, Charles, Fuchs, Donald L.
• Primary Examiner(s): Edwards, Jerrah
• Application Number:
  US10/838,517
• Publication Number:
  US 20050080561A1
• Time in Patent Office: 4,011 Days
• Field of Search: 701/213, 701/207, 701/214, 701/215, 701/216, 701/217, 701/220, 701/221, 701/469, 701/471, 701/473, 701/478, 340/932.2, 340/988, 342/357.06, 342/358, 342/422, 342/357.01, 342/450, 342/463, 342/357.1, 342/357.03, 342/357.09, 342/357.08, 342/357.02, 342/352, 342/378, 342/357.12, 342/357.15, 455/457, 455/561, 455/524, 455/575, 455/422, 455/426, 455/427, 455/456, 375/136, 375/150, 375/316, 375/325, 375/340
• US Class Current: 701/478
• CPC Class Codes: G01S 19/05 providing aiding data
• CPC Class Codes: G01S 19/235 Calibration of receiver components
• CPC Class Codes: G01S 19/252 Employing an initial estimate of location in generating assistance data
• CPC Class Codes: G01S 19/256 relating to timing, e.g. time of week, code phase, timing offset
• 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 19/37 Hardware or software details of the signal processing chain
• CPC Class Codes: G01S 2205/002 for traffic control, mobile tracking, guidance, surveillance or anti-collision
• CPC Class Codes: G01S 5/0036 of measured values, i.e. measurement on mobile and position calculation on base station
• CPC Class Codes: G06F 17/15 Correlation function computation including computation of convolution operations arithmetic circuits for sum of products per se, e.g. multiply-accumulators G06F7/5443; digital filters, e.g. FIR, IIR, adaptive filters H03H17/00
• CPC Class Codes: H04B 1/70752 Partial correlation
• CPC Class Codes: H04B 1/70754 Setting of search window, i.e. range of code offsets to be searched H04B1/70758 takes precedence
• CPC Class Codes: H04B 1/70757 with increased resolution, i.e. higher than half a chip H04B1/70758 takes precedence
• CPC Class Codes: H04B 1/7077 Multi-step acquisition, e.g. multi-dwell, coarse-fine or validation
• CPC Class Codes: H04B 2201/70715 with application-specific features

Abstract

Method and apparatus for processing a satellite positioning system (SPS) signal is described. In one example, a timing reference related to a SPS time of day is obtained from a wireless communication signal received by a mobile receiver. A bias in a local clock of the mobile receiver with respect to a frame timing of a repeating code broadcast by the satellite is compensated for in response to the timing reference. An expected code delay window is obtained for the SPS signal at the mobile receiver. The SPS signal is correlated with a reference code within the expected code delay window. In another example, an expected code delay window is obtained at the mobile receiver. The mobile receiver selects a sampling resolution in response to a size of the expected code delay window. The SPS signal is sampled at the selected sampling resolution and then correlated with a reference code.

Claims

1. A mobile receiver, comprising:

a processor configured to obtain an expected code delay window based on an expected pseudorange for a satellite; and

a satellite signal receiver configured to receive a satellite positioning system signal broadcast by said satellite, to select a sampling rate in response to a size of said expected code delay window and a predicted pseudo range rate, to sample said satellite positioning system signal at said selected sampling rate, and to correlate said sampled satellite positioning system signal with a reference code; and

accumulation circuitry configured to perform magnitude accumulation on said satellite positioning system signal within said expected code delay window.

2. The mobile receiver of claim 1, further comprising:

a communications device configured to receive external aiding data at said mobile receiver;

wherein said processor is configured to obtain said expected code delay window in response to said external aiding data.

3. The mobile receiver of claim 2, wherein said communications device comprises a wireless transceiver configured to receive a wireless communication signal containing said external aiding data.

4. The mobile receiver of claim 2, wherein said external aiding data comprises a time synchronization signal, and wherein said satellite signal receiver is further configured to compensate for a bias in a local clock in response to said time synchronization signal.

5. The mobile receiver of claim 2, wherein said external aiding data comprises acquisition assistance data.

6. The mobile receiver of claim 2, wherein said external aiding data comprises satellite trajectory data.

7. The mobile receiver of claim 1, wherein the processor receives the expected code delay window from an external ground-based transceiver.

8. The mobile receiver of claim 7, wherein said external ground-based transceiver forms a portion of a cellular telephone network.

9. The mobile receiver of claim 3, wherein the wireless communication signal is a broadcast signal.

10. The mobile receiver of claim 9, wherein the wireless communication signal is broadcast on a dedicated control channel.

11. A mobile receiver, comprising:

a satellite signal receiver configured to obtain an expected code delay window based on an expected pseudorange for a satellite, to receive a satellite positioning system signal broadcast by said satellite, to select a sampling rate in response to a size of said expected code delay window and a predicted pseudo range rate, to sample said satellite positioning system signal at said selected sampling rate, and to correlate said sampled satellite positioning system signal with a reference code; and

accumulation circuitry configured to perform magnitude accumulation on said satellite positioning system signal within said expected code delay window.

12. The mobile receiver of claim 11, further comprising:

a communications device configured to receive external aiding data at said mobile receiver;

wherein said expected code delay window is obtained in response to said external aiding data.

13. The mobile receiver of claim 12, wherein said communications device comprises a wireless transceiver configured to receive a wireless communication signal containing said external aiding data.

14. The mobile receiver of claim 12, wherein said external aiding data comprises a time synchronization signal, and wherein said satellite signal receiver is further configured to compensate for a bias in a local clock in response to said time synchronization signal.

15. The mobile receiver of claim 12, wherein said external aiding data comprises acquisition assistance data.

16. The mobile receiver of claim 12, wherein said external aiding data comprises satellite trajectory data.

17. The mobile receiver of claim 11, wherein the satellite signal receiver receives the expected code delay from an external ground-based transceiver.

18. The mobile receiver of claim 17, wherein said external ground-based transceiver forms a portion of a cellular telephone network.

19. The mobile receiver of claim 13, wherein the wireless communication signal is a broadcast signal.

20. The mobile receiver of claim 19, wherein the wireless communication signal is broadcast on a dedicated control channel.

21. A mobile receiver, comprising:

a satellite signal receiver configured to obtain a predicted pseudo range rate for a satellite, to receive a satellite positioning system signal broadcast by said satellite, to select a sampling rate in response to the predicted pseudo range rate, to sample said satellite positioning system signal at said selected sampling rate, and to correlate said sampled satellite positioning system signal with a reference code; and

accumulation circuitry configured to perform magnitude accumulation on said satellite positioning system signal within said expected code delay window.

22. The mobile receiver of claim 21, further comprising:

a communications device configured to receive external aiding data at said mobile receiver.

23. The mobile receiver of claim 22, wherein said external aiding data comprises an expected code delay window.

24. The mobile receiver of claim 23, wherein the satellite signal receiver is further configured to select the sampling rate in response to said expected code delay window.

25. The mobile receiver of claim 22, wherein said communications device comprises a wireless transceiver configured to receive a wireless communication signal containing the external aiding data.

26. The mobile receiver of claim 22, wherein said external aiding data comprises a time synchronization signal, and wherein said satellite signal receiver is further configured to compensate for a bias in a local clock in response to said time synchronization signal.

27. The mobile receiver of claim 22, wherein said external aiding data comprises satellite trajectory data.