TECHNIQUES FOR FASTER TIME-TO-FIRST-FIX

• US 20140094199A1
• Filed: 09/28/2012
• Published: 04/03/2014
• Est. Priority Date: 09/28/2012
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Palanki, Ravi, Chao, Hui, Das, Saumitra Mohan, Gupta, Rajarshi, Khorashadi, Behrooz
• Granted Patent: US 9,448,298 B2
• Time in Patent Office: Days
• US Class Current: 455/456.5
• CPC Class Codes: G01S 19/05 providing aiding data
• CPC Class Codes: G01S 5/02523 Details of interaction of receiver with radio-map
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

Example methods, apparatuses, or articles of manufacture are disclosed herein that may be utilized, in whole or in part, to facilitate or support one or more operations or techniques for a relatively faster time-to-first-fix, such as for use in or with a mobile communication device. Briefly, in accordance with at least one implementation, a method may include transmitting a first message to a mobile device, the first message comprising abbreviated positioning assistance data; receiving a second message from the mobile device, the second message comprising an indication of a coarse location of the mobile device; and transmitting a third message to the mobile device, the third message comprising a detailed tiled radio heat map obtained based, at least in part, on the received indication of the coarse location of the mobile device.

Claims

1. A method comprising:

transmitting a first message to a mobile device, said first message comprising abbreviated positioning assistance data;

receiving a second message from said mobile device, said second message comprising an indication of a coarse location of said mobile device; and

transmitting a third message to said mobile device, said third message comprising a detailed tiled radio heat map obtained based, at least in part, on said received indication of said coarse location of said mobile device.

2. The method of claim 1, wherein said abbreviated positioning assistance data comprises locations of one or more wireless transmitters.

3. The method of claim 2, wherein said one or more wireless transmitters comprises one or more access points positioned at known locations.

4. The method of claim 1, wherein said coarse location of said mobile device is estimated based, at least in part, on one or more wireless signaling measurements of one or more wireless transmitters.

5. The method of claim 4, wherein said one or more wireless signaling measurements comprises at least one measurement indicative of a measured range to said one or more wireless transmitters.

6. The method of claim 4, wherein said coarse location of said mobile device is estimated in connection with at least one of the following:

a centroid of one or more stronger measurements of said one or more wireless signaling measurements;

a minimum mean square error (MMSE) estimation of said one or more wireless signaling measurements;

or any combination thereof.

7. The method of claim 4, wherein said one or more wireless signaling measurements comprises at least one of the following:

a received signal strength indicator (RSSI) measurement;

a round-trip delay time (RTT) measurement;

or any combination thereof.

8. The method of claim 1, wherein said abbreviated positioning assistance data comprises a sparse radio heat map.

9. The method of claim 1, wherein said detailed tiled radio heat map covers an area smaller than an area covered by a sparse radio heat map.

10. The method of claim 1, wherein said detailed tiled radio heat map covers an area substantially the same as an area covered by a sparse radio heat map.

11. The method of claim 10, wherein said sparse radio heat map covers an area identifiable via a plurality of location context identifiers (LCIs).

12. The method of claim 1, wherein said detailed tiled radio heat map covers an area identifiable via a single LCI.

13. The method of claim 1, wherein said abbreviated positioning assistance data comprises a selected radio heat map covering a portion of an area that includes said coarse location of said mobile device.

14. The method of claim 13, wherein said portion of said area is identifiable via an LCI.

15. The method of claim 14, wherein said LCI comprises at least one of the following:

a plurality of rectangular heat map tiles;

or a single rectangular heat map tile.

16. The method of claim 13, wherein said selected radio heat map comprises a single heat map tile.

17. The method of claim 1, wherein said indication of said coarse location of said mobile device comprises an indication of a direction from a center of a selected heat map tile towards a position fix of said mobile device.

18. The method of claim 17, wherein said position fix is estimated via a vector towards said position fix computed using, at least in part, an area associated with at least one additional heat map tile.

19. The method of claim 1, wherein said detailed tiled radio heat map comprises a heat map tile.

20. An apparatus comprising:

a mobile device comprising;

a wireless transceiver to communicate with a wireless network; and

one or more processors programmed with instructions to;

obtain a first message received at said wireless transceiver, said first message comprising abbreviated positioning assistance data;

initiate a transmission of a second message via said wireless transceiver, said second message comprising an indication of a coarse location of said mobile device; and

obtain a third message received at said wireless transceiver, said third message comprising a detailed tiled radio heat map selected based, at least in part, on said transmitted indication of said coarse location of said mobile device.

21. The apparatus of claim 20, wherein said abbreviated positioning assistance data comprises locations of one or more wireless transmitters.

22. The apparatus of claim 20, wherein said coarse location of said mobile device is estimated based, at least in part, on one or more wireless signaling measurements of said one or more wireless transmitters.

23. The apparatus of claim 20, wherein said abbreviated positioning assistance data comprises a sparse radio heat map.

24. The apparatus of claim 20, wherein said abbreviated positioning assistance data comprises a selected heat map tile covering a portion of an area that includes said coarse location of said mobile device.

25. The apparatus of claim 20, wherein said indication of said coarse location of said mobile device comprises an indication of a direction from a center of a selected heat map tile towards a position fix of said mobile device.

26. The apparatus of claim 25, wherein said position fix is estimated via a vector towards said position fix computed using, at least in part, an area associated with at least one additional heat map tile.

27. An apparatus comprising:

means for transmitting a first message to a mobile device, said first message comprising abbreviated positioning assistance data;

means for receiving a second message from said mobile device, said second message comprising an indication of a coarse location of said mobile device; and

means for transmitting a third message to said mobile device, said third message comprising a detailed tiled radio heat map obtained based, at least in part, on said received indication of said coarse location of said mobile device.

28. The apparatus of claim 27, wherein said abbreviated positioning assistance data comprises locations of one or more wireless transmitters.

29. The apparatus of claim 27, wherein said coarse location of said mobile device is estimated based, at least in part, on one or more wireless signaling measurements of one or more wireless transmitters.

30. The apparatus of claim 29, wherein said one or more wireless signaling measurements comprises at least one measurement indicative of a measured range to said one or more wireless transmitters.

31. The apparatus of claim 29, wherein said coarse location of said mobile device is estimated in connection with at least one of the following:

a centroid of one or more stronger measurements of said one or more wireless signaling measurements;

a minimum mean square error (MMSE) estimation of said one or more wireless signaling measurements;

or any combination thereof.

32. The apparatus of claim 29, wherein said one or more wireless signaling measurements comprises at least one of the following:

a received signal strength indicator (RSSI) measurement;

a round-trip delay time (RTT) measurement;

or any combination thereof.

33. The apparatus of claim 27, wherein said abbreviated positioning assistance data comprises a sparse radio heat map.

34. The apparatus of claim 27, wherein said detailed tiled radio heat map covers an area smaller than an area covered by a sparse radio heat map.

35. The apparatus of claim 27, wherein said detailed tiled radio heat map covers an area substantially the same as an area covered by a sparse radio heat map.

36. The apparatus of claim 35, wherein said sparse radio heat map covers an area identifiable via a plurality of location context identifiers (LCIs).

37. The apparatus of claim 27, wherein said detailed tiled radio heat map covers an area identifiable via a single LCI.

38. The apparatus of claim 27, wherein said abbreviated positioning assistance data comprises a selected radio heat map covering a portion of an area that includes said coarse location of said mobile device.

39. The apparatus of claim 38, wherein said selected radio heat map comprises a single heat map tile.

40. The apparatus of claim 27, wherein said indication of said coarse location of said mobile device comprises an indication of a direction from a center of a selected heat map tile towards a position fix of said mobile device.

41. The apparatus of claim 40, wherein said position fix is estimated via a vector towards said position fix computed using, at least in part, an area associated with at least one additional heat map tile.

42. The apparatus of claim 27, wherein said detailed tiled radio heat map comprises a heat map tile.

43. An article comprising:

a non-transitory storage medium having instructions stored thereon executable by a special purpose computing platform to;

initiate a transmission of a first message to a mobile device, said first message comprising abbreviated positioning assistance data;

obtain a second message received from said mobile device, said second message comprising an indication of a coarse location of said mobile device; and

initiate a transmission of a third message to said mobile device, said third message comprising a detailed tiled radio heat map obtained based, at least in part, on said received indication of said coarse location of said mobile device.

44. The article of claim 43, wherein said abbreviated positioning assistance data comprises locations of one or more wireless transmitters.

45. The article of claim 43, wherein said abbreviated positioning assistance data comprises a sparse radio heat map.

46. The article of claim 43, wherein said abbreviated positioning assistance data comprises a selected heat map tile covering a portion of an area that includes said coarse location of said mobile device.

47. The article of claim 43, wherein said indication of said coarse location of said mobile device comprises an indication of a direction from a center of a selected heat map tile towards a position fix of said mobile device.