METHODS AND APPARATUS FOR POSITION LOCATION IN A WIRELESS NETWORK

• US 20130163458A1
• Filed: 02/19/2013
• Published: 06/27/2013
• Est. Priority Date: 01/04/2006
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Mukkavilli, Krishna Kiran, Ling, Fuyun, Walker, Gordon Kent, Chari, Murali Ramaswamy
• Granted Patent: US 9,008,700 B2
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: G01S 5/0205 Details
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

Methods and apparatus for position location in a wireless network. In an aspect, a method is provided that includes determining whether a symbol to be transmitted is an active symbol, wherein the symbol comprises a plurality of subcarriers, and encoding identification information on a first portion of subcarriers if it is determined that the symbol is the active symbol. The method also includes encoding idle information on a second portion of subcarriers if it is determined that the symbol in not the active symbol. In an aspect, an apparatus includes detector logic configured to decode a plurality of symbols to determine identification information that identifies a plurality of transmitters, and to determine a plurality of channel estimate associated with the plurality of transmitters. The apparatus also includes position determination logic configured to calculate a device position based on the plurality of transmitters and the plurality of channel estimates.

Claims

1. A method for determining a position of a device in a network, the method comprising:

decoding a symbol comprising subcarriers to determine identification information that identifies a transmitter, the decoding comprising partitioning the subcarriers of the symbol;

determining a channel estimate associated with the transmitter; and

repeating the decoding and the determining for a plurality of symbols so that a plurality of transmitters associated with a plurality of channel estimates, respectively, are determined.

2. The method of claim 1, further comprising calculating a device position based at least in part on the plurality of transmitters and the plurality of channel estimates.

3. The method of claim 2, in which the calculating comprises performing calculations at a server or the device.

4. The method of claim 2, in which the calculating comprises using triangulation.

5. The method of claim 2, in which the calculating comprises accounting for fixed offsets applied by the plurality of transmitters.

6. The method of claim 1, in which the symbol is a positioning pilot symbol.

7. The method of claim 6, in which the positioning pilot symbol includes an increased cyclic prefix.

8. The method of claim 1, in which the partitioning comprises partitioning the subcarriers of the symbol into a plurality of interlaces.

9. The method of claim 8, in which the decoding further comprises decoding the plurality of interlaces to determine a wide area scrambler seed (WID) value or a local area scrambler seed (LID) value.

10. The method of claim 1, in which the determining comprises determining a transmission time associated with the transmitter.

11. The method of claim 1, in which the symbol comprises an Orthogonal Frequency Division Multiplexing (OFDM) symbol.

12. An apparatus for determining a position of a device in a network, the apparatus comprising:

means for decoding a symbol comprising subcarriers to determine identification information that identifies a transmitter, the means for decoding comprising means for partitioning the subcarriers of the symbol;

means for determining a channel estimate associated with the transmitter; and

means for repeating the decoding and the determining for a plurality of symbols so that a plurality of transmitters associated with a plurality of channel estimates, respectively, are determined.

13. The apparatus of claim 12, further comprising means for calculating a device position based at least in part on the plurality of transmitters and the plurality of channel estimates.

14. The apparatus of claim 12, further comprising means for providing information to a server for calculating a device position based at least in part on the plurality of transmitters and the plurality of channel estimates.

15. The apparatus of claim 13, in which the means for calculating the device position comprises means for using triangulation.

16. The apparatus of claim 13, in which the means for calculating the device position comprises means for accounting for fixed offsets applied by the plurality of transmitters.

17. The apparatus of claim 12, in which the symbol is a positioning pilot symbol.

18. The apparatus of claim 17, in which the positioning pilot symbol includes an increased cyclic prefix.

19. The apparatus of claim 12, in which the means for partitioning comprises means for partitioning the subcarriers of the symbol into a plurality of interlaces.

20. The apparatus of claim 19, in which the means for decoding comprises means for decoding the plurality of interlaces to determine one of a wide area scrambler seed (WID) value or a local area scrambler seed (LID) value.

21. The apparatus of claim 12, in which the means for determining comprises means for determining a transmission time associated with the transmitter.

22. The apparatus of claim 12, in which the symbol comprises an Orthogonal Frequency Division Multiplexing (OFDM) symbol.

23. A computer program product for determining a position of a device in a network, the computer program product comprising:

a non-transitory computer-readable medium having program code recorded thereon, the program code comprising;

program code to decode a symbol comprising subcarriers to determine identification information that identifies a transmitter, the program code to decode comprising program code to partition the subcarriers of the symbol;

program code to determine a channel estimate associated with the transmitter; and

program code to repeat the decoding and the determining for a plurality of symbols so that a plurality of transmitters associated with a plurality of channel estimates, respectively, are determined.

24. The computer program product of claim 23, further comprising program code to calculate a device position based at least in part on the plurality of transmitters and the plurality of channel estimates.

25. The computer program product of claim 24, in which the program code to calculate comprises program code to perform calculations at a server or the device.

26. The computer program product of claim 24, in which the program code to calculate comprises program code to use triangulation.

27. The computer program product of claim 24, in which the program code to calculate comprises program code to account for fixed offsets applied by the plurality of transmitters.

28. The computer program product of claim 23, in which the symbol is a positioning pilot symbol.

29. The computer program product of claim 28, in which the positioning pilot symbol includes an increased cyclic prefix.

30. The computer program product of claim 23, in which the program code to partition comprises program code to partition the subcarriers of the symbol into a plurality of interlaces.

31. The computer program product of claim 30, in which the program code to decode further comprises program code to decode the plurality of interlaces to determine one of a wide area scrambler seed (WID) value or a local area scrambler seed (LID) value.

32. The computer program product of claim 23, in which the program code to determine a channel estimate associated with the transmitter comprise the program code to determine a transmission time associated with the transmitter.

33. The computer program product of claim 23, in which the symbol comprises an Orthogonal Frequency Division Multiplexing (OFDM) symbol.

34. An apparatus configured to determine a position of a device in a network, the apparatus comprising:

a memory unit; and

at least one processor coupled to the memory unit;

the at least one processor configured;

to decode a symbol comprising subcarriers to determine identification information that identifies a transmitter, in which the decoding comprises partitioning the subcarriers of the symbol;

to determine a channel estimate associated with the transmitter using the subcarriers of the symbol; and

to repeat the decoding and the determining for a plurality of symbols so that a plurality of transmitters associated with a plurality of channel estimates, respectively, are determined.

35. The apparatus of claim 34, in which the at least one processor is further configured to calculate a device position based at least in part on the plurality of transmitters and the plurality of channel estimates.

36. The apparatus of claim 34, in which the at least one processor is further configured to transmit information to a server for calculating a device position based at least in part on the plurality of transmitters and the plurality of channel estimates.

37. The apparatus of claim 35, in which the at least one processor is further configured to use triangulation to calculate the device position.

38. The apparatus of claim 35, in which the at least one processor is further configured to account for fixed offsets applied by the plurality of transmitters to calculate the device position.

39. The apparatus of claim 34, in which the symbol is a positioning pilot symbol.

40. The apparatus of claim 39, in which the positioning pilot symbol includes an increased cyclic prefix.

41. The apparatus of claim 34, in which the at least one processor is further configured to partition the subcarriers of the symbol into a plurality of interlaces.

42. The apparatus of claim 41, in which the at least one processor is further configured to decode the plurality of interlaces to determine one of a wide area scrambler seed (WID) value or a local area scrambler seed (LID) value.

43. The apparatus of claim 34, the at least one processor is further configured to determine a transmission time associated with the transmitter.

44. The apparatus of claim 34, in which the symbol comprises an Orthogonal Frequency Division Multiplexing (OFDM) symbol.