Position estimating for a mobile device

• US 9,020,523 B2
• Filed: 09/02/2011
• Issued: 04/28/2015
• Est. Priority Date: 07/12/2011
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Moeglein, Mark Leo, Rowitch, Douglas Neal, Zhang, Gengsheng, Gupta, Rajarshi
• Primary Examiner(s): Batista, Marcos
• Application Number:
  US13/225,316
• Publication Number:
  US 20130017840A1
• Time in Patent Office: 1,334 Days
• Field of Search: 455/456.1, 370/338
• US Class Current: 455/456.1
• CPC Class Codes: G01S 19/25 involving aiding data received from a cooperating element, e.g. assisted GPS
• CPC Class Codes: G01S 5/0278 involving statistical or probabilistic considerations G01S5/0252, G01S5/0294 take precedence

Abstract

Disclosed are methods, techniques and/or systems for selecting and/or determining a strategy and/or approach for searching for signals at a mobile device. Characteristics of and/or information obtained from such searched signals may be used in estimating a location of the mobile device. In one particular example, a strategy and/or approach for searching for wireless signals may be based, at least in part, on an availability of resources at a mobile device.

Claims

1. A method performed by a mobile device, the method comprising:

storing data representative of one or more probabilistic models in a storage medium;

updating said data representative of said one or more probabilistic models based, at least in part, on historical statistical information for wireless signals, at least a portion of said historical statistical information being determined by said mobile device;

determining, by said mobile device, one or more particular wireless signals for which to search based, at least in part, on said updated data representative of said one or more probabilistic models, said one or more wireless signals to be transmitted by one or more wireless transmitters; and

searching for said one or more particular wireless signals, by said mobile device, to estimate a position of said mobile device at least partially in response to said determining.

2. The method of claim 1, wherein said historical statistical information comprises information indicative of at least search success rates associated with signals transmitted by at least one transmitter.

3. The method of claim 1, wherein said historical statistical information comprises information indicative of signal strengths associated with signals transmitted by at least one transmitter.

4. The method of claim 1, wherein the historical statistical information is associated with at least one position and identifier associated with said mobile device.

5. The method of claim 1, wherein the historical statistical information includes a list of a plurality of wireless signals searched by said mobile device.

6. The method of claim 5, wherein the list comprises an indication as to whether individual ones of said wireless signals were searched successfully by said mobile device.

7. The method of claim 1, wherein the historical statistical information includes an indication of power used to search said wireless signals.

8. The method of claim 1, wherein the historical statistical information includes a duration elapsed to acquire at least one searched wireless signal.

9. The method of claim 1, wherein said historical statistical information is provided to an aggregator as part of a bi-directional communication session.

10. The method of claim 9, wherein said bi-directional communication session includes transmission of information descriptive of a plurality of transmitter types.

11. The method of claim 10, wherein said information descriptive of said plurality of transmitter types is transmitted on a forward link in said bi-directional communication session.

12. The method of claim 10, wherein said information descriptive of said plurality of transmitter types is transmitted on a reverse link in said bi-directional communication session.

13. The method of claim 1, wherein said historical statistical information is received via a communication session, the method further comprising wirelessly broadcasting one or more signals representative of said approach over a broadcast network.

14. The method of claim 1, wherein said approach comprises a selection of at least one signal to be searched by a mobile station.

15. The method of claim 1, wherein said approach comprises an identification of a particular transmitter type and/or specific transmitter to be searched.

16. The method of claim 15, wherein said approach further comprises specification of a Doppler window of said particular transmitter type and/or specific transmitter to be searched.

17. The method of claim 15, wherein said approach further comprises specification of a time window of said particular transmitter type and/or specific transmitter to be searched.

18. The method of claim 1, wherein said approach comprises a selection of a search mode from a plurality of search modes.

19. The method of claim 1, and further comprising determining said approach subject to a target accuracy level associated with a position estimate to be obtained from searching said wireless signals.

20. The method of claim 1, and further comprising determining said approach subject to a power consumption constraint.

21. The method of claim 1, and further comprising determining said approach subject to a target time to position fix.

22. The method of claim 1, and further comprising determining said approach based, at least in part, on a score determined from a plurality of factors.

23. The method of claim 22, wherein said plurality of factors comprises at least one of likely power consumption, likely accuracy, likely time to fix, an observed signal strength, a size of coverage area serving the mobile device or a type of transmitter.

24. The method of claim 1, wherein said historical statistical information is associated with attempts to search signals transmitted from at least one bi-directional wireless access point.

25. The method of claim 1, wherein said historical statistical information is associated with attempts to search signals from at least one broadcast-only transmitter.

26. The method of claim 1, wherein said historical statistical information is associated with attempts to search signals from at least one broadcast-only transmitter and at least one bi-directional wireless access point.

27. The method of claim 1, wherein said historical statistical information is associated with attempts to search signals for use in at least one communication application.

28. The method of claim 27, wherein said historical statistical information is based, at least in part, upon a pilot strength measurement message (PSMM) in a 1×

Code Division Multiple Access (CDMA) system.

29. The method of claim 27, wherein the historical statistical information is based, at least in part, on a network measurement response (NMR) in a Global System for Mobile Communications (GSM) system.

30. The method of claim 27, wherein the historical statistical information is based, at least in part, on a Measured Results List (MRL) of a Universal Mobile Telecommunications Service (UMTS) or Long Term Evolution (LTE) system.

31. The method of claim 1, and further comprising:

receiving said historical statistical information from a plurality of sources at an aggregating entity; and

updating said data representative of said one or more probabilistic models based, at least in part, on said received historical statistical information at said aggregating entity.

32. The method of claim 31, wherein said determined approach comprises a particular approach for searching for said one or more wireless signals at the mobile device, and wherein said aggregating entity is located within said mobile device.

33. The method of claim 31, wherein said determined approach comprises a particular approach for searching for said one or more wireless signals at a first mobile device, and wherein said aggregating entity is located within a second mobile device.

34. The method of claim 31, wherein said aggregating entity is located at a network entity configured to communicate with one or more mobile devices in a wireless or wired communication network.

35. The method of claim 34, said network entity is further configured to maintain information representative of estimates of transmitter positions and/or transmitter coverage areas.

36. The method of claim 1, wherein said historical statistical information is received from a plurality of sources, and wherein the method further comprises:

aggregating said historical statistical information; and

updating said data representative of said one or more probabilistic models based, at least in part, on said aggregated historical statistical information.

37. The method of claim 36, wherein said aggregated historical statistical information comprises transmitter timing information.

38. The method of claim 37, wherein said transmitter timing information is representative of a relationship between a framing structure of a signal transmitted by at least one transmitter and a time source.

39. The method of claim 37, wherein said transmitter timing information comprises an error estimate.

40. The method of claim 36, wherein said aggregated historical statistical information comprises an identification of one or more transmitters within a region.

41. The method of claim 40, wherein said aggregated historical statistical information identifies said one or more transmitters within said region using a hierarchical identification structure.

42. The method of claim 41, wherein said region is covered by a GSM system, and wherein said hierarchical identification structure is defined, at least in part, according to a location area code (LAC).

43. The method of claim 41, wherein said region is covered by a UMTS system, and wherein said hierarchical identification structure is defined, at least in part, according to a radio network controller (RNC).

44. The method of claim 41, wherein said region is covered by an LTE system, and wherein said hierarchical identification structure is defined, at least in part, according to a subset of a global cell identifier.

45. The method of claim 1, and further comprising searching for said one or more wireless signals using said determined approach.

46. The method of claim 1, and further comprising determining said approach based, at least in part, on observed signal strength.

47. The method of claim 1, and further comprising determining said approach based, at least in part, on a size of a coverage area.

48. The method of claim 1, and further comprising determining said approach based, at least in part, on a type of transmitter transmitting the one or more wireless signals.

49. The method of claim 1, wherein the historical statistical information includes an expected received signal strength of at least one wireless signal transmitted from a transmitter at a known location.

50. The method of claim 1, wherein the historical statistical information includes an expected round trip time of at least one wireless signal transmitted from a transmitter at a known location.

51. The method of claim 1, and wherein determining said approach further comprises determining a time for reattempting to acquire one or more signals transmitted by at least one of said one or more transmitters based, at least in part, on the updated data.

52. An article of a mobile device comprising:

a non-transitory storage medium comprising machine-readable instructions stored thereon which are executable by a processor to;

update data representative of one or more probabilistic models stored in a memory based, at least in part, on historical statistical information for wireless signals, at least a portion of said historical statistical information being determined by said mobile device;

determine one or more particular wireless signals for which to search based, at least in part, on updated data representative of said one or more probabilistic models, said one or more wireless signals to be transmitted by one or more wireless transmitters; and

search for said one or more particular wireless signals to estimate a position of said mobile device at least partially in response to determining said one or more particular wireless signals for which to search.

53. A mobile device comprising:

one or more receivers to receive and process wireless signals; and

one or more processors programmed with instructions to

update data representative of one or more probabilistic models based, at least in part, on historical statistical information for wireless signals, at least a portion of said historical statistical information being determined by said mobile device;

determine one or more particular wireless signals for which to search based, at least in part, on said updated data representative of said one or more probabilistic models, said one or more wireless signals to be transmitted by one or more wireless transmitters; and

initiate searching for said one or more particular wireless signals to estimate a position of said mobile device at least partially in response to determining said one or more particular wireless signals for which to search.

54. A mobile device comprising:

means for maintaining data representative of one or more probabilistic models in a storage medium;

means for updating said data representative of said one or more probabilistic models based, at least in part, on historical statistical information for wireless signals, at least a portion of said historical statistical information being determined by said mobile device;

means for determining one or more particular wireless signals for which to search based, at least in part, on said updated data representative of said one or more probabilistic models, said one or more wireless signals to be transmitted by one or more wireless transmitters; and

means for searching for said one or more particular wireless signals to estimate a position of said mobile device at least partially in response to determining said one or more particular wireless signals for which to search.