Selecting a position fix to determine the location of a wireless communication device

• US 8,184,563 B2
• Filed: 12/15/2010
• Issued: 05/22/2012
• Est. Priority Date: 07/23/2003
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Riley, Wyatt Thomas, Moeglein, Mark Leo, Biacs, Zoltan F.
• Primary Examiner(s): Qureshi, Afsar M.
• Application Number:
  US12/969,293
• Publication Number:
  US 20110105149A1
• Time in Patent Office: 524 Days
• Field of Search: 342350-903, 342/988, 342/991, 701116-226, 370310-345, 455/343.1, 455/414.3, 455/456.3, 340988-996
• US Class Current: 370/310.2
• CPC Class Codes: G01S 19/05 providing aiding data
• CPC Class Codes: G01S 19/06 employing an initial estimate of the location of the receiver as aiding data or in generating aiding data
• CPC Class Codes: G01S 19/46 the supplementary measurement being of a radio-wave signal type
• CPC Class Codes: G01S 19/48 by combining or switching between position solutions derived from the satellite radio beacon positioning system and position solutions derived from a further system
• CPC Class Codes: G01S 5/0236 Assistance data, e.g. base station almanac
• CPC Class Codes: G08G 1/096811 where the route is computed offboard
• CPC Class Codes: G08G 1/096883 where input information is obtained using a mobile device, e.g. a mobile phone, a PDA

Abstract

Different types of position fixes may be used to determine the location of a mobile station in a wireless communication system. The position fixes include terrestrial, or network, based techniques, and non-network based techniques, such as satellite, based techniques. An apparatus and method are presented by which different position fixes may be selected, based on the performance of a particular position fix in a particular mobile remote unit.

Claims

1. A method of determining a geographic position of a remote unit in a wireless communication system, comprising:

determining a first position solution of the remote unit using a first set of position data;

determining a second position solution of the remote unit using a second set of position data; and

selecting between the first position solution and the second position solution based on a predetermined selection criteria, wherein the first position solution and the second position solution are based upon separate measurements.

2. The method of claim 1 wherein the first set of position data include network-based measurements.

3. The method of claim 2 wherein the network-based measurements include pilot phase measurements.

4. The method of claim 2 wherein the network-based measurements include a round trip delay measurement.

5. The method of claim 2 wherein the network-based measurements include an angle of arrival measurement.

6. The method of claim 2 wherein the network-based measurements include a time of arrival measurement.

7. The method of claim 2 wherein the network-based measurements include a time difference of arrival measurement.

8. The method of claim 1 wherein the second set of data include non-network-based measurements.

9. The method of claim 8 wherein the non-network-based measurements include satellite based measurements.

10. The method of claim 8 wherein the non-network-based measurements include global positioning system measurements.

11. The method of claim 8 wherein the non-network-based measurements include geometric dilution of precision measurements.

12. The method of claim 8 wherein the non-network-based measurements include position dilution of precision measurements.

13. The method of claim 8 wherein the non-network-based measurements include horizontal dilution of precision measurements.

14. The method of claim 8 wherein the non-network-based measurements include weighted dilution of precision measurements.

15. The method of claim 8 wherein the non-network-based measurements include solution unit fault measurements.

16. The method of claim 8 wherein the non-network-based measurements include residual magnitudes measurements.

17. The method of claim 1 wherein selecting between the first position solution and the second position solution includes comparing respective figures of merit for the two position solutions.

18. The method of claim 17 wherein comparing includes evaluating the relative horizontal estimate of position error.

19. The method of claim 18 wherein comparing includes evaluating a relative geometric dilution of precision error.

20. The method of claim 18 wherein comparing includes evaluating the relative position of dilution of precision error.

21. The method of claim 18 wherein comparing includes evaluating the relative horizontal dilution of precision error.

22. The method of claim 18 wherein comparing includes evaluating the relative weighted dilution of precision errors.

23. The method of claim 18 wherein comparing includes evaluating the relative unit fault of the solution errors.

24. The method of claim 18 wherein comparing includes evaluating the relative measurement residual magnitudes.

25. The method of claim 18 wherein comparing is biased in favor of one of the position solutions.

28. The method of claim 1 wherein the remote unit is a mobile station.

26. The method of 25 wherein comparing is biased in favor of one of the position solutions unless an error metric of the other position is less than a threshold value wherein the other position solution is selected.

27. The method of claim 26 wherein the favored position solution is a global positioning system solution.

29. A position determination device in a wireless communication system, comprising:

a position engine configured to receive data produced from network signals and non-network signals and to process the data to determine at least two position solutions, wherein a first position solution and a second position solution are based upon separate measurements; and

a controller configured to select a desired position solution based on respective figures of merit of the position solutions.

30. The position determination device of claim 29 wherein the controller further includes the position engine.

31. The position determination device of claim 29 wherein the controller is further configured to generate acquisition assistance data based on a position solution processed using network-based data, wherein the acquisition assistance data is used by a remote unit in processing non-network-based signals.

32. The position determination device of claim 31 wherein the acquisition assistance data is generated using cell sector data.

33. The position determination device of claim 31 wherein the acquisition assistance data is generated using roundtrip delay data.

34. The position determination device of claim 31 wherein the acquisition assistance data is generated using angle of arrival data.

35. The position determination device of claim 31 wherein the acquisition assistance data is generated using time of arrival data.

36. The position determination device of claim 31 further including generating two sets of acquisition assistance data.

37. The position determination device of claim 31 wherein the acquisition assistance data assists the remote unit in processing global positioning system signals.

38. The position determination device of claim 29 wherein the data from non-network-based signals include signals from a global positioning system.

39. The position determination device of claim 29 wherein the data from network signals include pilot phase measurements.

40. The position determination device of claim 29 wherein the position determination device is included in a base station.

41. The position determination device of claim 29 wherein the position determination device is included in a wireless network infrastructure.

42. The position determination device of claim 29 wherein the position determination device is included in a remote unit.

43. A non-transitory machine readable medium embodying instructions for determining a geographic position of a remote unit in a wireless communication system, which when executed by a processor causes the processor to

determine a first position solution of the remote unit using a first set of position data;

determine a second position solution of the remote unit using a second set of position data; and

select between the first position solution and the second position solution based on a predetermined selection criteria, wherein the first position solution and the second position solution are based upon separate measurements.

44. The non-transitory machine readable medium of claim 43, embodying instructions when executed by the processor further causes the processor to

compare respective figures of merit for the two position solutions.

45. The non-transitory machine readable medium of claim 44 wherein comparing is biased in favor of one of the position solutions.

46. The non-transitory machine readable medium of claim 45, wherein comparing is biased in favor of one of the position solutions unless an error metric of the other position is less than a threshold value wherein the other position solution is selected.

47. A position determination device in a wireless communication system, comprising:

means for receiving data produced from network signals and non-network signals and to process the data to determine at least two position solutions, wherein a first position solution and a second position solution are based upon separate measurements; and

means for selecting a desired position solution based on respective figures of merit of the position solutions.

48. The position determination device of claim 47 wherein the means for selecting further includes generating acquisition assistance data based on a position solution processed using network-based data wherein the acquisition assistance data is used by a remote unit in processing non-network-based signals.

49. The position determination device of claim 48 wherein the data from non-network-based signals include signals from a global positioning system.

50. A method of determining a geographic position of a remote unit in a wireless communication system, comprising:

determining a first position solution of the remote unit using a first set of position data;

determining a second position solution of the remote unit using a second set of position data, wherein the first position solution and the second position solution are based upon separate measurements;

determining a pre-fix position solution of the remote unit for each of the first set of position data and the second set of position data;

selecting a desired one of the pre-fix position solutions based on figures of merit of the respective position solutions;

determining a final-fix position solution of the remote unit using at least one of the first set of position data and the second set of position data, and the selected pre-fix position solution; and

selecting a desired final position solution as the position of the remote unit based on respective figures of merit of the desired pre-fix position solution and the final-fix position solution.

51. An apparatus for determining a geographic position of a remote unit in a wireless communication system, comprising:

means for determining a first position solution of the remote unit using a first set of position data;

means for determining a second position solution of the remote unit using a second set of position data, wherein the first position solution and the second position solution are based upon separate measurements;

means for determining a pre-fix position solution of the remote unit for each of the first set of position data and the second set of position data;

means for selecting a desired one of the pre-fix position solutions based on figures of merit of the respective position solutions;

means for determining a final-fix position solution of the remote unit using at least one of the first set of position data and the second set of position data, and the selected pre-fix position solution; and

means for selecting a desired final position solution as the position of the remote unit based on respective figures of merit of the desired pre-fix position solution and the final-fix position solution.