LOCATION BASED TRACKING

• US 20080268869A1
• Filed: 04/24/2008
• Published: 10/30/2008
• Est. Priority Date: 04/26/2007
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Burroughs, Kirk Allan, Holcman, Alejandro R., Lamba, Gaurav, Deloach, James Douglas
• Granted Patent: US 8,019,356 B2
• Time in Patent Office: Days
• US Class Current: 455/456.1
• CPC Class Codes: G01S 5/011 Identifying the radio environment

Abstract

The subject matter disclosed herein relates to obtaining position fixes using a position determination method in response to a change in an RF environment.

Claims

1. A method comprising:

transitioning from obtaining one or more position fixes using a first position determination method to obtaining one or more position fixes using a second position determination method automatically and in response to detection of a first change in an RF environment based, at least in part, on a history of attempted position fixes; and

transitioning from obtaining one or more position fixes using said second position determination method to obtaining one or more position fixes using said first position determination method automatically and in response to detection of a second change in said RF environment.

2. The method of claim 1, wherein said transitioning from obtaining one or more position fixes using said second position determination method to obtaining one or more position fixes using said first position determination method further comprises:

detecting said second change in said RF environment in response to one or more successful attempted position fixes obtained using said first position determination method.

3. The method of claim 1, further comprising waiting a first duration before said transitioning from obtaining one or more position fixes using said second position determination method to obtaining one or more position fixes using said first position determination method.

4. The method of claim 3, further comprising:

obtaining one or more position fixes using said second position determination method for a second duration before said transitioning from said second position determination method to said first position determination method, wherein said second duration is longer than said first duration, in response to failure of said first position determination method to obtain one or more position fixes following waiting said first duration.

5. The method of claim 1, wherein said first position determination method comprises:

receiving data from a location server; and

determining a position fix at a mobile station based, at least in part, on said received data.

6. The method of claim 1, wherein said first position determination method comprises:

receiving data from navigation satellites; and

determining a position fix at a mobile station based, at least in part, on said received data.

7. The method of claim 1, wherein said second position determination method comprises:

determining a position fix at a location server; and

receiving said position fix at a mobile station from said location server.

8. The method of claim 1, wherein said first change in said RF environment comprises a change from an RF environment that allows obtaining a position fix at a mobile station using pseudorange measurements to satellite vehicles to an RF environment that prevents obtaining a position fix at said mobile station using said pseudorange measurements.

9. The method of claim 1, wherein said second change in said RF environment comprises a change from an RF environment that prevents obtaining a position fix at a mobile station using pseudorange measurements to satellite vehicles to an RF environment that allows obtaining a position fix at said mobile station using said pseudorange measurements.

10. The method of claim 4, wherein said failing to obtain a successful position fix comprises attempting two or more successive position fixes.

11. The method of claim 4, further comprising determining said second duration using a mathematical relationship based, at least in part, on said first duration.

12. The method of claim 11, wherein said mathematical relationship comprises an exponential relationship.

13. The method of claim 11, wherein said mathematical relationship comprises a linear relationship.

14. The method of claim 4, further comprising:

defining a geo-fence; and

determining said second duration based, at least in part, on whether or not a position fix is performed in said geo-fence.

15. The method of claim 4, further comprising:

determining a velocity; and

determining said second duration based, at least in part, on said velocity.

16. The method of claim 4, wherein said velocity is determined using two or more position fixes.

17. The method of claim 4, further comprising limiting said second duration to a maximum value.

18. A mobile station comprising:

a receiver adapted to operate in an RF environment to receive one or more satellite positioning system (SPS) signals; and

a transceiver adapted to communicate with a wireless communication network, said mobile station being adapted to;

transition from obtaining one or more position fixes based, at least in part, on said SPS signals using a first position determination method to obtaining one or more position fixes based, at least in part, on said SPS signals using a second position determination method using said transceiver automatically and in response to detection of a first change in said RF environment based, at least in part, on a history of attempted position fixes using said first position determination method, and

transition from obtaining one or more position fixes based, at least in part, on said SPS signals using said second position determination method using said transceiver to obtaining one or more position fixes based, at least in part, on said SPS signals using said first position determination method automatically and in response to detection of a second change in said RF environment.

19. The mobile station of claim 18, wherein said mobile station is further adapted to detect said second change in said RF environment in response to one or more successful attempted position fixes obtained using said first position determination method.

20. The mobile station of claim 18, wherein said mobile station is further adapted to wait a first duration before said transitioning from obtaining one or more position fixes using said second position determination method to obtaining one or more position fixes using said first position determination method.

21. The mobile station of claim 20, wherein said mobile station is further adapted to:

obtain one or more position fixes using said second position determination method for a second duration before said transitioning from said second position determination method to said first position determination method, wherein said second duration is longer than said first duration, in response to failure of said first position determination method to obtain one or more position fixes following waiting said first duration.

22. An article comprising:

a storage medium comprising machine-readable instructions stored thereon which, if executed by a computing platform, are adapted to enable said computing platform to;

transition from obtaining one or more position fixes using a first position determination method to obtaining one or more position fixes using a second position determination method automatically and in response to detection of a first change in an RF environment based, at least in part, on a history of attempted position fixes using said first position determination method; and

transition from obtaining one or more position fixes using said second position determination method to obtaining one or more position fixes using said first position determination method automatically and in response to detection of a second change in said RF environment.

23. The article of claim 22, wherein said instructions, if executed by said computing platform, are further adapted to enable said computing platform to detect said second change in said RF environment in response to one or more successful attempted position fixes obtained using said first position determination method.

24. The article of claim 22, wherein said instructions, if executed by said computing platform, are further adapted to enable said computing platform to wait a first duration before said transition from obtaining one or more position fixes using said second position determination method to obtaining one or more position fixes using said first position determination method.

25. The article of claim 24, wherein said instructions, if executed by said computing platform, are further adapted to enable said computing platform to:

obtain one or more position fixes using said second position determination method for a second duration before said transitioning from said second position determination method to said first position determination method, wherein said second duration is longer than said first duration, in response to failure of said first position determination method to obtain one or more position fixes following waiting said first duration.

26. The article of claim 22, wherein said first position determination method comprises:

receiving data from a location server; and

determining a position fix at a mobile station based, at least in part, on said received data.

27. An apparatus comprising:

means for transitioning from obtaining one or more position fixes using a first position determination method to obtaining one or more position fixes using a second position determination method automatically and in response to detection of a first change in an RF environment based, at least in part, on a history of attempted position fixes using said first position determination method; and

means for transitioning from obtaining one or more position fixes using said second position determination method to obtaining one or more position fixes using said first position determination method automatically and in response to detection of a second change in said RF environment.

28. The apparatus of claim 27, wherein said means for transitioning from obtaining one or more position fixes using said second position determination method to obtaining one or more position fixes using said first position determination method further comprises:

means for detecting said second change in said RF environment in response to one or more successful attempted position fixes obtained using said first position determination method.

29. The apparatus of claim 27, further comprising means for waiting a first duration before said transitioning from obtaining one or more position fixes using said second position determination method to obtaining one or more position fixes using said first position determination method.