METHODS AND APPARATUSES FOR ESTIMATING TIME RELATIONSHIP INFORMATION BETWEEN NAVIGATION SYSTEMS

• US 20110102253A1
• Filed: 11/04/2009
• Published: 05/05/2011
• Est. Priority Date: 11/04/2009
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Morrison, William James
• Granted Patent: US 9,244,176 B2
• Time in Patent Office: Days
• US Class Current: 342/357.25
• CPC Class Codes: G01S 19/33 Multimode operation in different systems which transmit time stamped messages, e.g. GPS/GLONASS
• CPC Class Codes: G01S 19/425 by combining or switching between signals derived from different satellite radio beacon positioning systems

Abstract

Methods and apparatuses are provided that may be implemented in various electronic devices to possibly reduce a first-time-to-fix and/or otherwise increase the performance or efficiency of a device by employing a position/velocity estimation process using at least one estimated time relationship parameter.

Claims

1. A method comprising:

with a device enabled to receive and process satellite positioning system (SPS) signals associated with at least first and second navigation systems;

generating one or more electronic signals representing an estimated time bias (TB) parameter associated with said device, said first navigation system, and said second navigation system;

selectively generating one or more electronic signals representing a pseudorange (PR) measurement corresponding to said device and at least one space vehicle (SV) of either said first or second navigation systems based, at least in part, on said estimated TB parameter; and

generating one or more electronic signals representing an estimated position of said device based, at least in part, on said PR.

2. The method as recited in claim 1, wherein said first navigation system is operatively associated with a first system time and said second navigation system is operatively associated with a second system time that is offset from said first system time by a dynamically changing offset value, and further comprising, with said device:

generating said one or more electronic signals representing said estimated TB parameter based, at least in part, on a time offset (TO) parameter associated with said dynamically changing offset value.

3. The method as recited in claim 2, wherein generating said one or more electronic signals representing said estimated TB parameter further comprises:

generating said one or more electronic signals representing said estimated TB parameter further based, at least in part, on a differential group delay (GD) parameter associated with said device.

4. The method as recited in claim 2, further comprising, with said device, at least one of:

receiving one or more electronic signals representing said TO parameter; and

/or

generating one or more electronic signals representing said TO parameter based, at least in part, on a previously stored TB parameter and/or a differential group delay (GD) parameter.

5. The method as recited in claim 3, wherein said differential GD parameter is predetermined.

6. The method as recited in claim 3, further comprising, with said device:

generating one or more electronic signals representing said differential GD parameter based, at least in part, on at least one of a temperature parameter and/or a previously stored TB parameter.

7. The method as recited in claim 1, wherein selectively generating said one or more electronic signals representing said PR measurement further comprises:

verifying that said estimated TB parameter is acceptable for use based, at least in part, on at least one uncertainty measurement associated with said estimated TB parameter.

8. The method as recited in claim 1, further comprising, with said device:

obtaining one or more electronic signals representing a first plurality of SPS signals associated with said first navigation system, wherein a first total number of available SPS signals associated with said first navigation system does not satisfy a minimum number of SPS signals to compute said estimated position of said device; and

obtaining one or more electronic signals representing at least one SPS signal associated with said second navigation system, and wherein a second total number of available SPS signals associated with said second navigation system also does not satisfy said minimum number of SPS signals to compute said estimated position of said device, but wherein said first and second total number of available SPS signals summed together does satisfy said minimum number of SPS signals to compute said estimated position of said device.

9. The method as recited in claim 8, wherein said minimum number of SPS signals to compute said estimated position of said device is three provided that an altitude parameter is available, or four otherwise.

10. The method as recited in claim 8, wherein said minimum number of SPS signals to compute said estimated position of said device is four provided that an altitude parameter is available, or five otherwise.

11. The method as recited in claim 1, wherein at least one of said first and/or second navigation systems comprises a Global Navigation Satellite System (GNSS).

12. An apparatus comprising:

means for receiving satellite positioning system (SPS) signals associated with at least first and second navigation systems;

means for determining an estimated time bias (TB) parameter associated with at least said first and second navigation systems;

means for selectively determining a pseudorange (PR) measurement corresponding to at least one space vehicle (SV) of either said first or second navigation systems based, at least in part, on said estimated TB parameter; and

means for determining an estimated position of said device based, at least in part, on said PR measurement.

13. The apparatus as recited in claim 12, wherein said first navigation system is operatively associated with a first system time and said second navigation system is operatively associated with a second system time that is offset from said first system time by a dynamically changing offset value, and further comprising:

means for determining said estimated TB parameter based, at least in part, on a time offset (TO) parameter associated with said dynamically changing offset value.

14. The apparatus as recited in claim 13, further comprising:

means for determining said estimated TB parameter based, at least in part, on a differential group delay (GD) parameter associated with said device.

15. The apparatus as recited in claim 13, further comprising at least one of:

means for receiving one or more electronic signals representing said TO parameter; and

/or

means for determining said TO parameter based, at least in part, on a previously stored TB parameter and/or a differential group delay (GD) parameter.

16. The apparatus as recited in claim 14, wherein said differential GD parameter is predetermined.

17. The apparatus as recited in claim 14, further comprising:

means for determining said differential GD parameter based, at least in part, on at least one of a temperature parameter and/or a previously stored TB parameter.

18. The apparatus as recited in claim 12, further comprising:

means for verifying that said estimated TB parameter is acceptable for use based, at least in part, on at least one uncertainty measurement associated with said estimated TB parameter.

19. The apparatus as recited in claim 12, further comprising:

means for obtaining one or more electronic signals representing a first plurality of SPS signals associated with said first navigation system, wherein a first total number of available SPS signals associated with said first navigation system does not satisfy a minimum number of SPS signals to compute said estimated position of said device; and

means for obtaining one or more electronic signals representing at least one SPS signal associated with said second navigation system, and wherein a second total number of available SPS signals associated with said second navigation system also does not satisfy said minimum number of SPS signals to compute said estimated position of said device, but wherein said first and second total number of available SPS signals summed together does satisfy said minimum number of SPS signals to compute said estimated position of said device.

20. The apparatus as recited in claim 19, wherein said minimum number of SPS signals to compute said estimated position of said device is three provided that an altitude parameter is available, or four otherwise.

21. The apparatus as recited in claim 19, wherein said minimum number of SPS signals to compute said estimated position of said device is four provided that an altitude parameter is available, or five otherwise.

22. The apparatus as recited in claim 12, wherein at least one of said first and/or second navigation systems comprises a Global Navigation Satellite System (GNSS).

23. An apparatus comprising:

memory having stored therein information associated with a plurality of different satellite positioning system (SPS) signals from a plurality of navigation systems comprising at least first and second navigation systems;

at least one processing unit operatively coupled to said memory to determine an estimated time bias (TB) parameter associated with at least said first and second navigation systems, selectively determine a pseudorange (PR) measurement corresponding to at least one space vehicle (SV) of either said first or second navigation systems based, at least in part, on said estimated TB parameter, and determine an estimated position of said device based, at least in part, on at least one of said PR measurement.

24. The apparatus as recited in claim 23, wherein said first navigation system is operatively associated with a first system time and said second navigation system is operatively associated with a second system time that is offset from said first system time by a dynamically changing offset value, and wherein said at least one processing unit determines said estimated TB parameter based, at least in part, on a time offset (TO) parameter associated with said dynamically changing offset value.

25. The apparatus as recited in claim 24, wherein said at least one processing unit determines said estimated TB parameter based, at least in part, on a differential group delay (GD) parameter associated with said device.

26. The apparatus as recited in claim 24, further comprising:

a receiver operatively coupled to at least one of said memory and/or said at least one processing unit, said receiver to receive said TO parameter and provide said TO parameter to at least one of said memory and/or said at least one processing unit.

27. The apparatus as recited in claim 24, wherein said at least one processing unit determines said TO parameter based, at least in part, on a previously stored TB parameter and/or a differential group delay (GD) parameter.

28. The apparatus as recited in claim 25, wherein said differential GD parameter is predetermined.

29. The apparatus as recited in claim 25, wherein said at least one processing unit determines said differential GD parameter based, at least in part, on at least one of a temperature parameter and/or a previously stored TB parameter.

30. The apparatus as recited in claim 23, wherein said at least one processing unit verifies that said estimated TB parameter is acceptable for use based, at least in part, on at least one uncertainty measurement associated with said estimated TB parameter.

31. The apparatus as recited in claim 23, wherein at least a portion of said information stored in said memory is associated with a first plurality of SPS signals associated with said first navigation system, wherein a first total number of available SPS signals associated with said first navigation system does not satisfy a minimum number of SPS signals to compute said estimated position of said device;

and

wherein at least another portion of said information stored in said memory is associated with at least one SPS signal associated with said second navigation system, and wherein a second total number of available SPS signals associated with said second navigation system also does not satisfy said minimum number of SPS signals to compute said estimated position of said device, but wherein said first and second total number of available SPS signals summed together does satisfy said minimum number of SPS signals to compute said estimated position of said device.

32. The apparatus as recited in claim 31, wherein said minimum number of SPS signals to compute said estimated position of said device is three provided that an altitude parameter is available, or four otherwise.

33. The apparatus as recited in claim 31, wherein said minimum number of SPS signals to compute said estimated position of said device is four provided that an altitude parameter is available, or five otherwise.

34. The apparatus as recited in claim 23, wherein at least one of said first and/or second navigation systems comprises a Global Navigation Satellite System (GNSS).

35. An article comprising:

a computer readable medium having computer implementable instructions stored thereon that in response to being executed by one or more processing units in an electronic device enable the electronic device to;

obtain satellite positioning system (SPS) signals associated with at least first and second navigation systems;

determine an estimated time bias (TB) parameter associated with at least said first and second navigation systems;

selectively determine a pseudorange (PR) measurement corresponding to at least one space vehicle (SV) of either said first or second navigation systems based, at least in part, on said estimated TB parameter; and

determine an estimated position of said device based, at least in part, on at least one of said PR measurement.

36. The article as recited in claim 35, wherein said first navigation system is operatively associated with a first system time and said second navigation system is operatively associated with a second system time that is offset from said first system time by a dynamically changing offset value, and further comprising:

means for determining said estimated TB parameter based, at least in part, on a time offset (TO) parameter associated with said dynamically changing offset value.

37. The article as recited in claim 36, wherein the computer implementable instructions in response to being executed by the one or more processing units in the electronic device further enable the electronic device to:

determine said estimated TB parameter based, at least in part, on a differential group delay (GD) parameter associated with said device.

38. The article as recited in claim 36, wherein the computer implementable instructions in response to being executed by the one or more processing units in the electronic device further enable the electronic device to:

obtain one or more electronic signals representing said TO parameter; and

/or

determine said TO parameter based, at least in part, on a previously stored TB parameter and/or a differential group delay (GD) parameter.

39. The article as recited in claim 37, wherein said differential GD parameter is predetermined.

40. The article as recited in claim 37, wherein the computer implementable instructions in response to being executed by the one or more processing units in the electronic device further enable the electronic device to:

determine said differential GD parameter based, at least in part, on at least one of a temperature parameter and/or a previously stored TB parameter.

41. The article as recited in claim 35, wherein the computer implementable instructions in response to being executed by the one or more processing units in the electronic device further enable the electronic device to:

verify that said estimated TB parameter is acceptable for use based, at least in part, on at least one uncertainty measurement associated with said estimated TB parameter.

42. The article as recited in claim 35, wherein the computer implementable instructions in response to being executed by the one or more processing units in the electronic device further enable the electronic device to:

obtain one or more electronic signals representing a first plurality of SPS signals associated with said first navigation system, wherein a first total number of available SPS signals associated with said first navigation system does not satisfy a minimum number of SPS signals to compute said estimated position of said device; and

obtain one or more electronic signals representing at least one SPS signal associated with said second navigation system, and wherein a second total number of available SPS signals associated with said second navigation system also does not satisfy said minimum number of SPS signals to compute said estimated position of said device, but wherein said first and second total number of available SPS signals summed together does satisfy said minimum number of SPS signals to compute said estimated position of said device.

43. The article as recited in claim 42, wherein said minimum number of SPS signals to compute said estimated position of said device is three provided that an altitude parameter is available, or four otherwise.

44. The article as recited in claim 42, wherein said minimum number of SPS signals to compute said estimated position of said device is four provided that an altitude parameter is available, or five otherwise.

45. The article as recited in claim 35, wherein at least one of said first and/or second navigation systems comprises a Global Navigation Satellite System (GNSS).