Estimating the Location of a Wireless Terminal Based on Assisted GPS and Pattern Matching

• US 20060240841A1
• Filed: 05/22/2006
• Published: 10/26/2006
• Est. Priority Date: 05/22/2006
• Status: Active Grant

• Current Assignee: Polaris Wireless Incorporated
• Original Assignee: Polaris Wireless Incorporated
• Inventors: Bhattacharya, Tarun Kumar
• Granted Patent: US 8,965,393 B2
• Time in Patent Office: Days
• US Class Current: 455/456.100
• 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 19/17 Emergency applications
• CPC Class Codes: G01S 19/252 Employing an initial estimate of location in generating assistance data
• CPC Class Codes: G01S 5/021 Calibration, monitoring or correction G01S5/0252 takes precedence
• 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 84/06 Airborne or Satellite Networks space-based or airborne stations H04B7/185

Abstract

A method of using a non-GPS-derived technique to estimate the location of an Assisted-GPS-enabled wireless terminal for the purposes of generating location-specific assistance data for the wireless terminal is disclosed. The wireless terminal then uses the assistance data to acquire and process one or more GPS signals and to derive information that is probative of the wireless terminal'"'"'s location. The GPS-derived location information is then combined with non-GPS-derived location to form an estimate of the location of the wireless terminal that is better than can be derived from either alone. This combination of GPS-derived and non-GPS techniques is particularly useful when the wireless terminal can only acquire one or two GPS signals because it is not possible to determine the location of the wireless terminal with only two GPS signals alone.

Claims

1. A process comprising:

generating a first non-GPS-derived estimate of the location of a wireless terminal based on a first measurement of a trait of a first signal; and

generating assistance data for a satellite signal that is received by said wireless terminal, wherein said assistance data is based on said first non-GPS-derived estimate of the location of said wireless terminal.

2. The process of claim 1 further comprising receiving a second estimate of the location of said wireless terminal from said wireless terminal based on said satellite signal.

3. The process of claim 2 further comprising generating a third estimate of the location of said wireless terminal based on said first measurement and said second estimate of the location of said wireless terminal.

4. The process of claim 2 further comprising generating a third estimate of the location of said wireless terminal based on said second estimate of the location of said wireless terminal and a second measurement of said trait of said first signal.

5. The process of claim 1 further comprising receiving ranging data from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said ranging data.

6. The process of claim 1 further comprising receiving ranging data from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said ranging data and said first measurement.

7. The process of claim 1 further comprising receiving ranging data from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said ranging data and a second measurement of said trait of said first signal.

8. The process of claim 1 further comprising receiving a partially-processed satellite signal from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said partially-processed satellite signal.

9. The process of claim 1 further comprising receiving a partially-processed satellite signal from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said partially-processed satellite signal and said first measurement.

10. The process of claim 1 further comprising receiving a partially-processed satellite signal from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said partially-processed satellite signal and a second measurement of said trait of said first signal.

11. The process of claim 1 wherein said assistance data is fully-custom based on said first non-GPS-derived estimate of the location of said wireless terminal.

12. The process of claim 1 wherein said assistance data is semi-custom based on said first non-GPS-derived estimate of the location of said wireless terminal.

13. A process comprising:

generating a first non-GPS-derived estimate of the location of a wireless terminal that is more accurate than an estimate based on cell ID alone; and

generating assistance data for a satellite signal that is received by said wireless terminal, wherein said assistance data is based on said first non-GPS-derived estimate.

14. The process of claim 13 further comprising receiving a second estimate of the location of said wireless terminal from said wireless terminal based on said satellite signal.

15. The process of claim 14 further comprising generating a third estimate of the location of said wireless terminal based on said second estimate of the location of said wireless terminal and said first non-GPS-derived estimate.

16. The process of claim 14 further comprising generating a third estimate of the location of said wireless terminal based on said second estimate of the location of said wireless terminal and an measurement of a trait of a first signal.

17. The process of claim 13 further comprising receiving ranging data from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said ranging data.

18. The process of claim 17 further comprising receiving ranging data from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said ranging data and said first non-GPS-derived estimate.

19. The process of claim 17 further comprising receiving ranging data from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said ranging data and an measurement of a trait of a first signal.

20. The process of claim 13 further comprising receiving a partially-processed satellite signal from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said partially-processed satellite signal.

21. The process of claim 13 further comprising receiving a partially-processed satellite signal from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said partially-processed satellite signal and said first non-GPS-derived estimate.

22. The process of claim 13 further comprising receiving partially-processed satellite signal from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said partially-processed satellite signal and an measurement of a trait of a first signal.

23. The process of claim 13 wherein said assistance data is fully-custom based on said first non-GPS-derived estimate of the location of said wireless terminal.

24. The process of claim 13 wherein said assistance data is semi-custom based on said first non-GPS-derived estimate of the location of said wireless terminal.

25. A process comprising:

generating a first non-GPS-derived estimate of the location of a wireless terminal based on comparing a first measurement of a trait of a first signal to a map that correlates locations with predicted values of said trait; and

generating assistance data for a satellite signal that is received by said wireless terminal, wherein said assistance data is based on said first non-GPS-derived estimate of the location of said wireless terminal.

26. The process of claim 25 further comprising receiving a second estimate of the location of said wireless terminal from said wireless terminal based on said satellite signal.

27. The process of claim 26 further comprising generating a third estimate of the location of said wireless terminal based on said first measurement and said second estimate of the location of said wireless terminal.

28. The process of claim 26 further comprising generating a third estimate of the location of said wireless terminal based on said second estimate of the location of said wireless terminal and a second measurement of said trait of said first signal.

29. The process of claim 25 further comprising receiving ranging data from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said ranging data.

30. The process of claim 25 further comprising receiving ranging data from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said ranging data and said first measurement.

31. The process of claim 25 further comprising receiving ranging data from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said ranging data and a second measurement of said trait of said first signal.

32. The process of claim 25 further comprising receiving a partially-processed satellite signal from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said partially-processed satellite signal.

33. The process of claim 25 further comprising receiving a partially-processed satellite signal from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said partially-processed satellite signal and said first measurement.

34. The process of claim 25 further comprising receiving a partially-processed satellite signal from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said partially-processed satellite signal and a second measurement of said trait of said first signal.

35. The process of claim 25 wherein said assistance data is fully-custom based on said first non-GPS-derived estimate of the location of said wireless terminal.

36. The process of claim 25 wherein said assistance data is semi-custom based on said first non-GPS-derived estimate of the location of said wireless terminal.

37. A process comprising:

generating a first assistance data for a satellite signal at a first location that is serviced by a base station;

generating a second assistance data for said satellite signal at a second location that is serviced by said base station;

generating a first non-GPS-derived estimate of the location of a wireless terminal that is serviced by said base station; and

transmitting said first assistance data to said wireless terminal when said first non-GPS-derived estimate of the location of said wireless terminal is closer to said first location than said second location, and transmitting said second assistance data to said wireless terminal when said first non-GPS-derived estimate of the location of said wireless terminal is closer to said second location than said first location

38. The process of claim 37 wherein said first non-GPS-derived estimate of the location of said wireless terminal is based on a first measurement of a trait of a first signal.

39. The process of claim 37 wherein said first non-GPS-derived estimate of the location of said wireless terminal that is more accurate than an estimate based on cell ID alone.

40. The process of claim 37 wherein said first non-GPS-derived estimate of the location of said wireless terminal is based on comparing a first measurement of a trait of a first signal to a map that correlates locations with predicted values of said trait.

41. The process of claim 37 further comprising receiving a second estimate of the location of said wireless terminal from said wireless terminal based on said satellite signal.

42. The process of claim 41 further comprising generating a third estimate of the location of said wireless terminal based on said first measurement and said second estimate of the location of said wireless terminal.

43. The process of claim 41 further comprising generating a third estimate of the location of said wireless terminal based on said second estimate of the location of said wireless terminal and a second measurement of said trait of said first signal.

44. The process of claim 37 further comprising receiving ranging data from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said ranging data.

45. The process of claim 37 further comprising receiving ranging data from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said ranging data and said first measurement.

46. The process of claim 37 further comprising receiving ranging data from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said ranging data and a second measurement of said trait of said first signal.

47. The process of claim 37 further comprising receiving a partially-processed satellite signal from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said partially-processed satellite signal.

48. The process of claim 37 further comprising receiving a partially-processed satellite signal from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said partially-processed satellite signal and said first measurement.

49. The process of claim 37 further comprising receiving a partially-processed satellite signal from said wireless terminal based on said satellite signal;

and

generating a second estimate of the location of said wireless terminal based on said partially-processed satellite signal and a second measurement of said trait of said first signal.