System and/or method for reducing ambiguities in received SPS Signals

• US 8,188,915 B2
• Filed: 09/17/2010
• Issued: 05/29/2012
• Est. Priority Date: 08/23/2006
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Pon, Rayman Wai, Farmer, Dominic Gerard
• Primary Examiner(s): Tarcza, Thomas
• Assistant Examiner(s): Mull, Fred H
• Application Number:
  US12/885,157
• Publication Number:
  US 20110006947A1
• Time in Patent Office: 620 Days
• Field of Search: 342/357.29, 342/357.43, 342/357.69, 342/357.71, 342/357.73
• US Class Current: 342/357.73
• CPC Class Codes: G01S 19/243 Demodulation of navigation message
• CPC Class Codes: G01S 19/252 Employing an initial estimate of location in generating assistance data
• CPC Class Codes: G01S 19/33 Multimode operation in different systems which transmit time stamped messages, e.g. GPS/GLONASS

Abstract

Systems, apparatuses, and/or methods are provided for resolving ambiguities associated with signals received from space vehicles (SVs) in a satellite navigation system. For example, certain methods include receiving a first SV signal from a first satellite positioning system (SPS), and reducing a bit edge ambiguity of a data signal modulating a second SV signal received from a second SPS based, at least in part, on information in the received first SV signal.

Claims

1. A method comprising:

acquiring a first navigation signal at a reference location;

estimating timing of a bit edge of a data signal modulating a second navigation signal received at said reference location based on the first navigation signal; and

performing pre-detection integration to acquire said second navigation signal over an interval of said second navigation signal based, at least in part, on said estimated timing of said bit edge, wherein said first navigation signal is transmitted according to a first format and second navigation signal is transmitted according to a second format different from said first format.

2. The method of claim 1, wherein said first navigation signal is transmitted by a first space vehicle (SV) and said second navigation signal is transmitted by a second SV, wherein said bit edge is synchronized with a known instance of said first navigation signal, and wherein said estimating said timing of said bid edge further comprises associating said known instance with said bit edge based, at least in part, on an estimated difference between a first range to said first SV from said reference location and a second range to a second SV from said reference location.

3. The method of claim 1, wherein said estimating said timing of said bit edge further comprises:

decoding an alternating Viterbi encoded signal modulating said first navigation signal; and

associating a transition of said decoded alternating Viterbi encoded signal with said bit edge.

4. The method of claim 1, wherein said estimating said timing of said bit edge further comprises:

decoding a repeating data sequence modulating said first navigation signal; and

associating said bit edge in said second signal with an instance of said decoded data sequence.

5. A method comprising:

acquiring a first navigation signal at a reference location;

estimating timing of a bit edge of a data signal modulating a second navigation signal received at said reference location based on the first navigation signal; and

performing pre-detection integration to acquire said second navigation signal over an interval of said second navigation signal based, at least in part, on said estimated timing of said bit edge, wherein said first navigation signal is transmitted from a first space vehicle (SV) that is a member of a Galileo or a Glonass constellation and said second navigation signal is transmitted from a second SV that is a member of a GPS constellation.

6. An apparatus comprising:

a receiver to acquire a first navigation signal at a reference location; and

a processor to;

estimate timing of a bit edge of a data signal modulating a second navigation signal received at said reference location based on the first navigation signal; and

perform pre-detection integration to acquire said second navigation signal over an interval of said second navigation signal based, at least in part, on said estimated timing of said bit edge, wherein said first navigation signal is transmitted according to a first format and second navigation signal is transmitted according to a second format different from said first format.

7. The apparatus of claim 6, wherein said first navigation signal is transmitted by a first space vehicle (SV) and said second navigation signal is transmitted by a second SV, wherein said bit edge is synchronized with a known instance of said first navigation signal, and said processor to further associate said known instance with said bit edge based, at least in part, on an estimated difference between a first range to said first SV from said reference location and a second range to a second SV from said reference location.

8. The apparatus of claim 6, said processor to further:

decode an alternating Viterbi encoded signal modulating said first navigation signal; and

associate a transition of said decoded alternating Viterbi encoded signal with said bit edge.

9. The apparatus of claim 6, said processor to further:

decode a repeating data sequence modulating said first navigation signal; and

associate said bit edge in said second signal with an instance of said decoded data sequence.

10. An apparatus comprising:

a receiver to acquire a first navigation signal at a reference location; and

a processor to;

estimate timing of a bit edge of a data signal modulating a second navigation signal received at said reference location based on the first navigation signal; and

perform pre-detection integration to acquire said second navigation signal over an interval of said second navigation signal based, at least in part, on said estimated timing of said bit edge, wherein said first navigation signal is transmitted from a first space vehicle (SV) that is a member of a Galileo or a Glonass constellation and said second navigation signal is transmitted from a second SV that is a member of a GPS constellation.

11. An apparatus comprising:

means for acquiring a first navigation signal at a reference location;

means for estimating timing of a bit edge of a data signal modulating a second navigation signal received at said reference location based on the first navigation signal; and

means for performing pre-detection integration to acquire said second navigation signal over an interval of said second navigation signal based, at least in part, on said estimated timing of said bit edge, wherein said first navigation signal is transmitted according to a first format and second navigation signal is transmitted according to a second format different from said first format.

12. The apparatus of claim 11, wherein said first navigation signal is transmitted by a first space vehicle (SV) and said second navigation signal is transmitted by a second SV, wherein said bit edge is synchronized with a known instance of said first navigation signal, and wherein said means for estimating said timing of said bid edge further comprises means for associating said known instance with said bit edge based, at least in part, on an estimated difference between a first range to said first SV from said reference location and a second range to a second SV from said reference location.

13. The apparatus of claim 11, wherein said means for estimating said timing of said bit edge further comprising:

means for decoding an alternating Viterbi encoded signal modulating said first navigation signal; and

means for associating a transition of said decoded alternating Viterbi encoded signal with said bit edge.

14. The apparatus of claim 11, wherein said means for estimating said timing of said bit edge further comprises:

means for decoding a repeating data sequence modulating said first navigation signal; and

means for associating said bit edge in said second signal with an instance of said decoded data sequence.

15. The apparatus comprising:

means for acquiring a first navigation signal at a reference location;

means for estimating timing of a bit edge of a data signal modulating a second navigation signal received at said reference location based on the first navigation signal; and

means for performing pre-detection integration to acquire said second navigation signal over an interval of said second navigation signal based, at least in part, on said estimated timing of said bit edge, wherein said first navigation signal is transmitted from a first space vehicle (SV) that is a member of a Galileo or a Glonass constellation and said second navigation signal is transmitted from a second SV that is a member of a GPS constellation.

16. An article comprising:

a non-transitory storage medium, said storage medium comprising machine-readable instructions stored thereon executable by a computing platform to;

acquire a first navigation signal at a reference location;

estimate timing of a bit edge of a data signal modulating a second navigation signal received at said reference location based on the first navigation signal; and

perform pre-detection integration to acquire said second navigation signal over an interval of said second navigation signal based, at least in part, on said estimated timing of said bit edge, wherein said first navigation signal is transmitted according to a first format and second navigation signal is transmitted according to a second format different from said first format.

17. An article comprising:

a non-transitory storage medium, said storage medium comprising machine-readable instructions stored thereon executable by a computing platform to;

acquire a first navigation signal at a reference location;

estimate timing of a bit edge of a data signal modulating a second navigation signal received at said reference location based on the first navigation signal; and

perform pre-detection integration to acquire said second navigation signal over an interval of said second navigation signal based, at least in part, on said estimated timing of said bit edge, wherein said first navigation signal is transmitted from a first space vehicle (SV) that is a member of a Galileo or a Glonass constellation and said second navigation signal is transmitted from a second SV that is a member of a GPS constellation.