Method and system for device positioning utilizing distributed transceivers with array processing

• US 8,818,418 B2
• Filed: 10/17/2013
• Issued: 08/26/2014
• Est. Priority Date: 08/06/2010
• Status: Expired due to Fees

• Current Assignee: Golba LLC
• Original Assignee: Golba LLC
• Inventors: Moshfeghi, Mehran
• Primary Examiner(s): Magloire, Vladimir
• Assistant Examiner(s): Fang, Keith
• Application Number:
  US14/056,864
• Publication Number:
  US 20140045527A1
• Time in Patent Office: 313 Days
• Field of Search: None
• US Class Current: 455/456.5
• CPC Class Codes: G01S 5/0018 Transmission from mobile station to base station
• CPC Class Codes: G01S 5/0226 Transmitters
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 4/025 using location based information parameters
• CPC Class Codes: H04W 4/029 Location-based management or tracking services
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

A mobile device receives RF signals from base stations in a location scanning region. Each of the base stations includes a plurality of distributed transceivers and each distributed transceiver includes an independently configurable antenna array. The mobile device generates and communicates channel measurements for the received radio frequency signals to a remote location server (RLS). The RLS configures, utilizing one or more channel transmit settings, the independently configurable antenna array for the distributed transceivers in the location scanning region, to transmit the RF signals. The RLS determines a coarse position estimate for the mobile device for the sub-regions within the location scanning region and applies different signature functions to the determined coarse position estimate for the sub-regions to generate corresponding sub-regions position estimates. The RLS determines a position estimate for the mobile device based on the sub-regions position estimates and communicates the position estimate to the mobile device.

Claims

1. A method of processing signals, the method comprising:

in a mobile device;

receiving radio frequency signals from one or more base stations, wherein;

each of said one or more base stations comprises a plurality of distributed transceivers; and

each of said plurality of distributed transceivers comprises an independently configurable antenna array for transmitting said radio frequency signals to said mobile device;

generating channel measurements for said received radio frequency signals; and

receiving a position estimate for said mobile device from a location server, wherein;

corresponding transmit diversity configurations are determined by said location server, said corresponding transmit diversity configurations being applied to said one or more base stations for both said channel measurements for said mobile device and channel measurements at scanned locations in a location scanning region;

said position estimate for said mobile device over said location scanning region utilizing said channel measurements for said mobile device, said channel measurements at said scanned locations, and said corresponding transmit diversity configurations are calculated by said location server;

a signature function for said channel measurements for said mobile device, and said channel measurements at said scanned locations over said corresponding transmit diversity configurations, are selected by said location server;

said signature function is utilized by said location server to determine said position estimate for said mobile device over said corresponding transmit diversity configurations;

said position estimate for said mobile device is updated by said location server based on a resolution of said signature function over said scanned locations in said location scanning region;

at least one of (i) a subset of said corresponding transmit diversity configurations and (ii) a subspace of said location scanning region is selected by said location server based on said resolution of said signature function over said scanned locations in said location scanning region; and

said signature function is utilized by said location server to calculate said updated position estimate for said mobile device over at least one of (i) said subset of said corresponding transmit diversity configurations and (ii) said subspace of said location scanning region.

2. The method according to claim 1, wherein said signature function is defined in terms of a full channel response, a received signal strength indicator, a strongest multipath, or an angle of arrival for said channel measurements for said mobile device, and said channel measurements at said scanned locations over said corresponding transmit diversity configurations.

3. The method according to claim 1, wherein said updated position estimate for said mobile device is calculated by said location server, by utilizing a different signature function for said channel measurements for said mobile device and said channel measurements with said scanned locations over said corresponding transmit diversity configurations.

4. The method according to claim 1, comprising receiving said updated position estimate at said mobile device.

29. The method according to claim 1, wherein the functionality of said location server is implemented in one or more of said base stations.

30. The method according to claim 1, wherein the functionality of said location server is implemented in said mobile device.

31. The method according to claim 1, wherein the functionality of said location server is implemented in a remote location server external to said mobile device and said one or more base stations.

5. A system for processing signals, the system comprising:

a mobile device, said mobile device being operable to;

receive radio frequency signals from one or more base stations, wherein;

each of said one or more base stations comprises a plurality of distributed transceivers; and

each of said plurality of distributed transceivers comprises an independently configurable antenna array for transmitting said radio frequency signals to said mobile device;

determine channel characteristics for said received radio frequency signals;

generate channel measurements for said received radio frequency signals; and

receive a position estimate for said mobile device from a location server, wherein;

corresponding transmit diversity configurations are determined by said location server, said corresponding transmit diversity configurations being applied to said one or more base stations for both said channel measurements for said mobile device and channel measurements at scanned locations in a location scanning region;

said position estimate for said mobile device over said location scanning region utilizing said channel measurements for said mobile device, said channel measurements at said scanned locations, and said corresponding transmit diversity configurations are calculated by said location server;

a signature function for said channel measurements for said mobile device, and said channel measurements at said scanned locations over said corresponding transmit diversity configurations, are selected by said location server;

said signature function is utilized by said location server to determine said position estimate for said mobile device over said corresponding transmit diversity configurations;

said position estimate for said mobile device is updated by said location server based on a resolution of said signature function over said scanned locations in said location scanning region;

at least one of (i) a subset of said corresponding transmit diversity configurations and (ii) a subspace of said location scanning region is selected by said location server based on said resolution of said signature function over said scanned locations in said location scanning region; and

said signature function is utilized by said location server to calculate said updated position estimate for said mobile device over at least one of (i) said subset of said corresponding transmit diversity configurations and (ii) said subspace of said location scanning region.

6. The system according to claim 5, wherein said signature function is defined in terms of a full channel response, a received signal strength indicator, a strongest multipath, or an angle of arrival for said channel measurements for said mobile device, and said channel measurements at said scanned locations over said corresponding transmit diversity configurations.

7. The method according to claim 5, wherein said updated position estimate for said mobile device is calculated by said location server, by utilizing a different signature function for said channel measurements for said mobile device and said channel measurements with said scanned locations over said corresponding transmit diversity configurations.

8. The system according to claim 5, wherein said mobile device receives said updated position estimate.

32. The system according to claim 5, wherein the functionality of said location server is implemented in one or more of said base stations.

33. The system according to claim 5, wherein the functionality of said location server is implemented in said mobile device.

34. The system according to claim 5, wherein the functionality of said location server is implemented in a remote location server external to said mobile device and said one or more base stations.

9. A method for processing signals, the method comprising:

in a mobile device;

receiving radio frequency signals from one or more base stations in a location scanning region, wherein;

each of said one or more base stations comprises a plurality of distributed transceivers; and

each of said plurality of distributed transceivers comprises an independently configurable antenna array for transmitting said radio frequency signals to said mobile device;

communicating channel measurements generated by said mobile device for said received radio frequency signals to a location server, wherein said location server;

configures, utilizing one or more channel transmit settings, said independently configurable antenna array for said plurality of distributed transceivers in said one or more base stations in said location scanning region to transmit said radio frequency signals;

determines a coarse position estimate for said mobile device for each of a plurality of sub-regions within said location scanning region;

applies a plurality of different signature functions to said determined coarse position estimate for said each of said plurality of sub-regions to generate corresponding sub-regions position estimates; and

determines a position estimate for said mobile device based on said sub-regions position estimates; and

receiving said position estimate for said mobile device from said location server.

10. The method according to claim 9, wherein said location server customizes said each of said plurality of different signature functions for said each of said plurality of sub-regions.

11. The method according to claim 10, wherein said each of said plurality of different signature functions is customized for said each of said plurality of sub-regions based on said one or more channel transmit settings.

12. The method according to claim 9, wherein said location server generates corresponding location estimation resolution and error for each of said generated corresponding sub-regions position estimates.

13. The method according to claim 12, wherein said location server sorts said generated corresponding sub-regions position estimates based on said generated corresponding location estimation resolution and error.

14. The method according to claim 13, wherein said location server discards one or more of said generated corresponding sub-regions position estimates that do not improve said generated corresponding location estimation resolution and error above a threshold.

15. The method according to claim 14, wherein said location server utilizes said one or more of said generated corresponding sub-regions position estimates, which improves said generated corresponding location estimation resolution and error above said threshold, for said determination of said position estimate for said mobile device.

16. The method according to claim 14, wherein said threshold is programmable.

17. The method according to claim 13, wherein said location server filters one or more variables that do not improve said generated corresponding location estimation resolution and error above a threshold.

18. The method according to claim 17, wherein said one or more variables comprises antenna phase array coefficients for said independently configurable antenna array in each of said plurality of distributed transceivers, carrier frequencies utilized by said one or more base stations in said location scanning region, a number of said one or more base stations in said location scanning region that are utilized, and a number of said plurality of distributed transceivers that are utilized.

35. The method according to claim 9, wherein the functionality of said location server is implemented in one or more of said base stations.

36. The method according to claim 9, wherein the functionality of said location server is implemented in said mobile device.

37. The method according to claim 9, wherein the functionality of said location server is implemented in a remote location server external to said mobile device and said one or more base stations.

19. A system for processing signals, the system comprising:

a mobile device, said mobile device is operable to;

receive radio frequency signals from one or more base stations in a location scanning region, wherein;

each of said one or more base stations comprises a plurality of distributed transceivers; and

each of said plurality of distributed transceivers comprises an independently configurable antenna array for transmitting said radio frequency signals to said mobile device;

communicate channel measurements generated by said mobile device for said received radio frequency signals to a location server, wherein said location server;

configures, utilizing one or more channel transmit settings, said independently configurable antenna array for said plurality of distributed transceivers in said one or more base stations in said location scanning region to transmit said radio frequency signals;

determines a coarse position estimate for said mobile device for each of a plurality of sub-regions within said location scanning region;

applies a plurality of different signature functions to said determined coarse position estimate for said each of said plurality of sub-regions to generate corresponding sub-regions position estimates; and

determines a position estimate for said mobile device based on said sub-regions position estimates; and

receive said position estimate for said mobile device from said location server.

20. The system according to claim 19, wherein said location server customizes said each of said plurality of different signature functions for said each of said plurality of sub-regions.

21. The system according to claim 20, wherein said each of said plurality of different signature functions is customized for said each of said plurality of sub-regions based on said one or more channel transmit settings.

22. The system according to claim 19, wherein said location server generates corresponding location estimation resolution and error for each of said generated corresponding sub-regions position estimates.

23. The system according to claim 22, wherein said location server sorts said generated corresponding sub-regions position estimates based on said generated corresponding location estimation resolution and error.

24. The system according to claim 23, wherein said location server discards one or more of said generated corresponding sub-regions position estimates that do not improve said generated corresponding location estimation resolution and error above a threshold.

25. The system according to claim 24, wherein said location server utilizes said one or more of said generated corresponding sub-regions position estimates, which improves said generated corresponding location estimation resolution and error above said threshold, for said determination of said position estimate for said mobile device.

26. The system according to claim 24, wherein said threshold is programmable.

27. The system according to claim 23, wherein said location server filters one or more variables that do not improve said generated corresponding location estimation resolution and error above a threshold.

28. The system according to claim 27, wherein said one or more variables comprises antenna phase array coefficients for said independently configurable antenna array in each of said plurality of distributed transceivers, carrier frequencies utilized by said one or more base stations in said location scanning region, a number of said one or more base stations in said location scanning region that are utilized, and a number of said plurality of distributed transceivers that are utilized.

38. The system according to claim 19, wherein the functionality of said location server is implemented in one or more of said base stations.

39. The system according to claim 19, wherein the functionality of said location server is implemented in said mobile device.

40. The system according to claim 19, wherein the functionality of said location server is implemented in a remote location server external to said mobile device and said one or more base stations.