Methods and apparatuses using mixed navigation system constellation sources for time setting

• US 8,866,671 B2
• Filed: 11/04/2009
• Issued: 10/21/2014
• Est. Priority Date: 11/04/2009
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Morrison, William James
• Primary Examiner(s): McGue, Frank J
• Application Number:
  US12/612,598
• Publication Number:
  US 20110102260A1
• Time in Patent Office: 1,812 Days
• Field of Search: 342/357.73
• US Class Current: 342/357.73
• CPC Class Codes: G01S 19/256 relating to timing, e.g. time of week, code phase, timing offset
• CPC Class Codes: G01S 19/33 Multimode operation in different systems which transmit time stamped messages, e.g. GPS/GLONASS

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 using portions of system time identifiers from different systems to determine at least one navigation system time.

Claims

1. A method comprising:

with a satellite positioning system (SPS) receiver enabled device;

obtaining one or more electronic signals representing partial first system time information, said partial first system time information comprising one or more portions but not all of a first system time identifier identifying a system time, wherein the system time is an instance of an incrementing time value associated with a first navigation system;

obtaining one or more electronic signals representing second system time information, said second system time information comprising at least a portion of a second system time identifier associated with a second system, wherein said first navigation system and said second system comprise different Global Navigation Satellite Systems; and

generating one or more electronic signals operatively identifying a first system time associated with said first navigation system based, at least in part, on said partial first system time information and at least said portion of said second system time information, wherein the at least said portion of said second system time information provides information on one or more of the missing portions of time of said partial first system time information.

2. The method as recited in claim 1, wherein said first system time identifier comprises a plurality of data portions that together identify said first system time.

3. The method as recited in claim 2, wherein at least two of said plurality of data portions are periodically transmitted by said first navigation system at different intervals.

4. The method as recited in claim 2, wherein said partial first system time information comprises a subset of said plurality of data portions.

5. The method as recited in claim 2, wherein each of the plurality of data portions represent a separate and distinct portion of the linear sequence of time, that together identify said first system time, and wherein at least one of said plurality of data portions has not been obtained, and wherein generating said one or more electronic signals operatively identifying said first system time further comprises operatively substituting at least said portion of said second system time information for said at least one of said plurality of data portions that has not been obtained, wherein the at least said portion of said second system time information does not overlap in time with any of the data portions in the plurality of data portions that has been obtained.

6. The method as recited in claim 5, wherein operatively substituting at least said portion of said second system time information for said at least one of said plurality of data portions that has not been obtained further comprises at least one of:

converting at least said portion of said second system time information for use with said partial first system time information, and/or

converting at least a portion of said partial first system time information for use with at least said portion of said second system time information.

7. The method as recited in claim 1, wherein said one or more electronic signals operatively identifying said first system time specifies a first system time offset operatively associated with a locally maintained time.

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

with said SPS receiver enabled device;

obtaining one or more electronic signals representing third system time information, said third system time information comprising at least a portion of a third system time identifier associated with a third system, and wherein generating said one or more electronic signals operatively identifying said first system time further comprises generating said one or more electronic signals operatively identifying said first system time based also, at least in part, on at least said portion of said third system time information.

9. The method of claim 1, further comprising:

determining to be unable to identify the first system time based on only the partial first system time information.

10. The method of claim 1, wherein said partial first system time information and at least said portion of said second system time information used to generate said one or more electronic signals comprises data indicative of four-year interval number, GLONASS calendar day number in four-year interval, and GPS time of week.

11. The method of claim 1, wherein said partial first system time information and at least said portion of said second system time information used to generate said one or more electronic signals comprises data indicative of GPS week number, GLONASS calendar day number in four-year interval, and GLONASS time of day.

12. An apparatus comprising:

means for obtaining partial first system time information, said partial first system time information comprising one or more portions but not all of a first system time identifier identifying a system time, wherein the system time is an instance of an incrementing time value associated with a first navigation system;

means for obtaining second system time information, said second system time information comprising at least a portion of a second system time identifier associated with a second system, wherein said first navigation system and said second system comprise different Global Navigation Satellite Systems; and

means for identifying a first system time associated with said first navigation system based, at least in part, on said partial first system time information and at least said portion of said second system time information, wherein the at least said portion of said second system time information provides information on one or more of the missing portions of time of said partial first system time information.

13. The apparatus as recited in claim 12, wherein said first system time identifier comprises a plurality of data portions that together identify said first system time.

14. The apparatus as recited in claim 13, wherein at least two of said plurality of data portions are periodically transmitted by said first navigation system at different intervals.

15. The apparatus as recited in claim 13, wherein said partial first system time information comprises a subset of said plurality of data portions.

16. The apparatus as recited in claim 13, wherein each of the plurality of data portions represents a separate and distinct portion of the linear sequence of time, that together identify said first system time, and wherein at least one of said plurality of data portions has not been obtained, and further comprising:

means for operatively substituting at least said portion of said second system time information for said at least one of said plurality of data portions that has not been obtained, wherein the at least said portion of said second system time information does not overlap in time with any of the data portions in the plurality of data portions that has been obtained.

17. The apparatus as recited in claim 16, further comprising at least one of:

means for converting at least said portion of said second system time information for use with said partial first system time information, and/or

means for converting at least a portion of said partial first system time information for use with at least said portion of said second system time information.

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

means for obtaining a locally maintained time; and

wherein said first system time specifies a first system time offset operatively associated with said locally maintained time.

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

means for obtaining third system time information, said third system time information comprising at least a portion of a third system time identifier associated with a third system, and wherein said means for identifying said first system time further identifies said first system time based also, at least in part, on at least said portion of said third system time information.

20. An apparatus comprising:

memory having stored therein partial first system time information, said partial first system time information comprising one or more portions but not all of a first system time identifier identifying a system time, wherein the system time is an instance of an incrementing time value associated with a first navigation system, and second system time information, said second system time information comprising at least a portion of a second system time identifier associated with a second system, wherein said first navigation system and said second system comprise different Global Navigation Satellite Systems; and

one or more processing units coupled to said memory and operable to identify a first system time associated with said first navigation system based, at least in part, on said partial first system time information and at least said portion of said second system time information, wherein the at least said portion of said second system time information provides information on one or more of the missing portions of time of said partial first system time information.

21. The apparatus as recited in claim 20, wherein said first system time identifier comprises a plurality of data portions that together identify said first system time.

22. The apparatus as recited in claim 21, further comprising:

a satellite positioning system (SPS) receiver coupled to at least one of said memory and/or said one or more processing units and operable to receive at least two of said plurality of data portions as periodically transmitted by said first navigation system at different intervals.

23. The apparatus as recited in claim 21, wherein said partial first system time information comprises a subset of said plurality of data portions.

24. The apparatus as recited in claim 21, wherein each of the plurality of data portions represents a separate and distinct portion of the linear sequence of time, that together identify said first system time, and wherein at least one of said plurality of data portions is unavailable in said memory, and wherein said one or more processing units is operable to substitute at least said portion of said second system time information for said at least one of said plurality of data portions that is unavailable in said memory, wherein the at least said portion of said second system time information does not overlap in time with any of the data portions in the plurality of data portions that has been obtained.

25. The apparatus as recited in claim 24, wherein said one or more processing units is further operable to convert at least said portion of said second system time information for use with said partial first system time information, and/or

convert at least a portion of said partial first system time information for use with at least said portion of said second system time information.

26. The apparatus as recited in claim 20, wherein said first system time specifies a first system time offset operatively associated with a locally maintained time.

27. The apparatus as recited in claim 20, wherein said memory has stored therein third system time information, said third system time information comprising at least a portion of a third system time identifier associated with a third system, and wherein said one or more processing units further identifies said first system time based also, at least in part, on at least said portion of said third system time information.

28. The apparatus of claim 20, wherein the one or more processing units is further operable to determine to be unable to identify the first system time based on only the partial first system time information.

29. The apparatus of claim 20, wherein said partial first system time information and at least said portion of said second system time information used to generate said one or more electronic signals comprises data indicative of four-year interval number, GLONASS calendar day number in four-year interval, and GPS time of week.

30. The method of claim 20, wherein said partial first system time information and at least said portion of said second system time information used to generate said one or more electronic signals comprises data indicative of GPS week number, GLONASS calendar day number in four-year interval, and GLONASS time of day.

31. An article comprising:

a non-transitory 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;

access partial first system time information, said partial first system time information comprising one or more portions but not all of a first system time identifier identifying a system time, wherein the system time is an instance of an incrementing time value associated with a first navigation system;

access second system time information, said second system time information comprising at least a portion of a second system time identifier associated with a second system, wherein said first navigation system and said second system comprise different Global Navigation Satellite Systems; and

identify a first system time associated with said first navigation system based, at least in part, on said partial first system time information and at least said portion of said second system time information, wherein the at least said portion of said second system time information provides information on one or more of the missing portions of time of said partial first system time information.

32. The article as recited in claim 31, wherein said first system time identifier comprises a plurality of data portions that together identify said first system time.

33. The article as recited in claim 32, wherein at least two of said plurality of data portions are periodically transmitted by said first navigation system at different intervals.

34. The article as recited in claim 32, wherein said partial first system time information comprises a subset of said plurality of data portions.

35. The article as recited in claim 32, wherein each of the plurality of data portions represents a separate and distinct portion of the linear sequence of time, and wherein at least one of said plurality of data portions is unavailable, and 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:

operatively substituting at least said portion of said second system time information for said at least one of said plurality of data portions that is unavailable, wherein the at least said portion of said second system time information does not overlap in time with any of the data portions in the plurality of data portions that is available.

36. 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:

convert at least said portion of said second system time information for use with said partial first system time information, and/or

convert at least a portion of said partial first system time information for use with at least said portion of said second system time information.

37. The article as recited in claim 31, wherein said first system time specifies a first system time offset operatively associated with said locally maintained time.

38. The article as recited in claim 31, 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:

access third system time information, said third system time information comprising at least a portion of a third system time identifier associated with a third system; and

identify said first system time based also, at least in part, on at least said portion of said third system time information.