Multiple pass location processor

• US 6,873,290 B2
• Filed: 04/15/2003
• Issued: 03/29/2005
• Est. Priority Date: 01/08/1999
• Status: Expired due to Term

• Current Assignee: Skyhook Holding, Inc. (Liberty Broadband Corp.)
• Original Assignee: TruePosition Incorporated
• Inventors: Anderson, Robert J., Ward, Matthew L., Stilp, Louis A.
• Primary Examiner(s): PHAN, DAO LINDA
• Application Number:
  US10/414,982
• Publication Number:
  US 20040017312A1
• Time in Patent Office: 714 Days
• Field of Search: 342/357.01, 342/357.02, 342/451, 342/457, 342/463, 455/456, 455/457
• US Class Current: 342/457
• CPC Class Codes: G01S 1/026 of associated receivers
• CPC Class Codes: G01S 2205/06 Emergency
• CPC Class Codes: G01S 5/021 Calibration, monitoring or correction G01S5/0252 takes precedence
• CPC Class Codes: G01S 5/0244 Accuracy or reliability of position solution or of measurements contributing thereto
• CPC Class Codes: G01S 5/06 Position of source determined by co-ordinating a plurality of position lines defined by path-difference measurements G01S5/12 takes precedence
• CPC Class Codes: H04W 4/90 Services for handling of emergency or hazardous situations, e.g. earthquake and tsunami warning systems [ETWS]
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: H04W 76/50 for emergency connections

Abstract

A multiple pass location processing method, for use in a wireless location system (WLS), comprises identifying a received transmission as requiring multiple pass location processing whereby the WLS produces a first, lower quality location estimate and then subsequently produces a second, higher quality location estimate. The WLS then produces the first location estimate and provides it to a first location application, and then produces the second location estimate. The second location estimate may be a more accurate estimate than the first location estimate and/or of a higher confidence than the first location estimate. This method is suitable, but not limited, for use in connection with locating a wireless transmitter involved in an emergency services call and routing the call to a call center.

Claims

1. A method for use in a Wireless Location System (WLS) capable of locating a mobile transmitter and delivering location estimates to one or more location-based applications, wherein a location estimation process is performed according to one or more quality-of-service parameters, comprising the steps of:

(a) assigning at least a first and a second set of predetermined quality-of-service parameters to a specific call class or mobile transmitter identity;

(b) producing a first location estimate in a process whereby the collection of signal data and location calculation processing have been constrained by the first set of quality-of-service parameters;

(c) delivering the first location estimate to at least one of the said one or more location-based applications;

(d) producing a second location estimate with a process whereby the collection of signal data and location calculation processing have been constrained by the second set of quality-of-service parameters; and

(e) delivering the second location estimate to at least one of the said one or more location-based applications.

2. The method recited in claim 1, wherein at least one of the quality-of-service parameters is determined by the type of location-based application to which a location estimate is to be provided.

3. The method recited in claim 1, wherein at least one of the quality-of-service parameters is determined by the called number.

4. The method recited in claim 1, wherein at least one of the quality-of-service parameters is determined by the calling number.

5. The method recited in claim 1, wherein at least one of the quality-of-service parameters is determined by the mobile transmitter'"'"'s identification.

6. The method recited in claim 1, wherein at least one of the quality-of-service parameters includes a priority level.

7. The method recited in claim 1, wherein at least one of the quality-of-service parameters includes a time limit on signal collection.

8. The method recited in claim 1, wherein at least one of the quality-of-service parameters includes a time limit on signal processing.

9. The method recited in claim 1, wherein at least one of the quality-of-service parameters includes a time limit on total latency.

10. The method recited in claim 1, wherein at least one of the quality-of-service parameters include a signal power threshold.

11. The method recited in claim 1, wherein at least one of the quality-of-service parameters include a time limit for delivery of a location estimate.

12. The method recited in claim 1, wherein at least one of the quality-of-service parameters includes a location accuracy threshold.

13. The method recited in claim 1, wherein at least one of the quality-of-service parameters includes a velocity accuracy threshold.

14. The method recited in claim 1, wherein the second location estimate is independent of the first location estimate.

15. The method recited in claim 1, wherein the second location estimate is at least partially based on the first location estimate.

16. The method recited in claim 1, wherein the first location estimate and the second location estimate are determined in parallel.

17. The method recited in claim 1, wherein the location-based application of step (e) is not the same as the location-based application in step (c).

18. The method recited in claim 1, wherein step (d) comprises multiple location estimations with the period between estimates set by the second set of quality-of-service parameters.

19. The method recited in claim 1, wherein step (d) comprises multiple location estimations with the number set by the second set of quality-of-service parameters.

20. The method recited in claim 1, wherein step (d) comprises multiple location estimations with the total time period set by the second set of quality-of-service parameters.

21. The method recited in claim 1, wherein the first location estimate and second location estimate include an information element identifying the location estimate as either the first location estimate or second location estimate.

22. A multiple pass location processing method for use in a wireless location system (WLS) capable of locating a wireless transmitter based on a transmission received from the wireless transmitter, comprising the steps of:

(a) selecting a first location technology based on a first set of quality-of-service parameters and a stored radio environmental and propagation model;

(b) producing a first, lower quality location estimate and providing said first location estimate to a first location application;

c) selecting a second location technology based on the first set of quality-of-service parameters and the stored radio environmental and propagation model; and

(d) subsequently producing a second, higher quality location estimate for delivery to a second location application.

23. A method as recited in claim 22, wherein a site density factor is employed in determining the technology used for the first location estimation.

24. A method as recited in claim 22, wherein the first set of quality-of-service parameters contains a time limit to be used in determining the technology to be used for the first location estimation.

25. A method as recited in claim 22, wherein the first set of quality-of-service parameters contains a confidence factor used in determining the technology to be used for the first location estimation.

26. A method as recited in claim 22, wherein the first set of quality-of-service parameters contains an accuracy parameter used in determining the technology used for the first location estimation.

27. A method as recited in claim 22, wherein the second set of quality-of-service parameters contains a confidence factor used in determining the technology used for the second location estimation.

28. A method as recited in claim 22, wherein the second set of quality-of-service parameters contains an accuracy requirement used in determining the technology used for the second location estimation.

29. A method as recited in claim 22, wherein the second set of quality-of-service parameters contains a time limit used in determining the technology used for the second location estimation.

30. A Wireless Location System (WLS) capable of locating a mobile transmitter and delivering location estimates to one or more location-based applications, wherein a location estimation process is performed according to one or more quality-of-service parameters, comprising:

(a) means for assigning at least a first and a second set of predetermined quality-of-service parameters to a specific call class or mobile transmitter identity;

(b) means for producing a first location estimate in a process whereby the collection of signal data and location calculation processing have been constrained by the first set of quality-of-service parameters;

(c) means for transmitting the first location estimate to at least one of the said one or more location-based applications;

(d) means for producing a second location estimate with a process whereby the collection of signal data and location calculation processing have been constrained by the second set of quality-of-service parameters; and

(e) means for transmitting the second location estimate to at least one of the said one or more location-based applications.

31. The system recited in claim 30, wherein at least one of the quality-of-service parameters is determined by the type of location-based application to which a location estimate is to be provided.

32. The system recited in claim 30, wherein at least one of the quality-of-service parameters is determined by the called number.

33. The system recited in claim 30, wherein at least one of the quality-of-service parameters is determined by the calling number.

34. The system recited in claim 30, wherein at least one of the quality-of-service parameters is determined by the mobile transmitter'"'"'s identification.

35. The system recited in claim 30, wherein at least one of the quality-of-service parameters includes a priority level.

36. The system recited in claim 30, wherein at least one of the quality-of-service parameters includes a time limit on signal collection.

37. The system recited in claim 30, wherein at least one of the quality-of-service parameters includes a time limit on signal processing.

38. The system recited in claim 30, wherein at least one of the quality-of-service parameters includes a time limit on total latency.

39. The system recited in claim 30, wherein at least one of the quality-of-service parameters include a signal power threshold.

40. The system recited in claim 30, wherein at least one of the quality-of-service parameters include a time limit for delivery of a location estimate.

41. The system recited in claim 30, wherein at least one of the quality-of-service parameters includes a location accuracy threshold.

42. The system recited in claim 30, wherein at least one of the quality-of-service parameters includes a velocity accuracy threshold.

43. The system recited in claim 30, wherein the second location estimate is independent of the first location estimate.

44. The system recited in claim 30, wherein the second location estimate is at least partially based on the first location estimate.

45. The system recited in claim 30, wherein the first location estimate and the second location estimate are determined in parallel.

46. The system recited in claim 30, comprising means for producing multiple location estimations with the period between estimates set by the second set of quality-of-service parameters.

47. The system recited in claim 30, comprising means for producing multiple location estimations with the number set by the second set of quality-of-service parameters.

48. The system recited in claim 30, comprising means for producing multiple location estimations with the total time period set by the second set of quality-of-service parameters.

49. A multiple pass location processing system for use in a wireless location system (WLS) capable of locating a wireless transmitter based on a transmission received from the wireless transmitter, comprising the steps of:

(a) means for selecting a first location technology based on a first set of quality-of-service parameters and a stored radio environmental and propagation model;

(b) means for producing a first, lower quality location estimate and providing said first location estimate to a first location application;

(c) means for selecting a second location technology based on the first set of quality-of-service parameters and the stored radio environmental and propagation model; and

(d) means for subsequently producing a second, higher quality location estimate for delivery to a second location application.

50. A system as recited in claim 49, wherein a site density factor is employed in determining the technology used for the first location estimation.

51. A system as recited in claim 49, wherein the first set of quality-of-service parameters contains a time limit to be used in determining the technology to be used for the first location estimation.

52. A system as recited in claim 49, wherein the first set of quality-of-service parameters contains a confidence factor used in determining the technology to be used for the first location estimation.

53. A system as recited in claim 49, wherein the first set of quality-of-service parameters contains an accuracy parameter used in determining the technology used for the first location estimation.

54. A system as recited in claim 49, wherein the second set of quality-of-service parameters contains a confidence factor used in determining the technology used for the second location estimation.

55. A system as recited in claim 49, wherein the second set of quality-of-service parameters contains an accuracy requirement used in determining the technology used for the second location estimation.

56. A system as recited in claim 49, wherein the second set of quality-of-service parameters contains a time limit used in determining the technology used for the second location estimation.