METHOD AND APPARATUS FOR TWO-WAY RANGING

• US 20100128617A1
• Filed: 07/31/2009
• Published: 05/27/2010
• Est. Priority Date: 11/25/2008
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Naguib, Ayman Fawzy, Sridhara, Vinay, Aggarwal, Alok
• Granted Patent: US 9,125,153 B2
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H04W 56/009 Closed loop measurements

Abstract

The subject matter disclosed herein relates to a system and method for wirelessly receiving a first communication from a first mobile device. A processing delay may be measured. An acknowledgement communication indicating receipt of the first communication may be generated. A measurement of the processing delay may be broadcast in a broadcast packet, for example, or by transmitting a subsequent communication including the processing delay in response to receiving a second communication having a request for the measurement of the processing delay.

Claims

1. A method, comprising:

wirelessly receiving a first communication from a first mobile device;

measuring a processing delay; and

generating an acknowledgement communication indicating receipt of the first communication.

2. The method of claim 1, further comprising transmitting a subsequent communication comprising a measurement of the processing delay in response to receiving a second communication having a request for the measurement of the processing delay.

3. The method of claim 2, wherein the measurement of the processing delay comprises a most recently measured time interval.

4. The method of claim 2, wherein the measurement of the processing delay comprises a measured time interval and a timestamp at which the processing delay was measured.

5. The method of claim 2, wherein at least one of the first communication and the second communication comprises a packet-based communication.

6. The method of claim 1, further comprising broadcasting a measurement of the processing delay in a broadcast packet.

7. The method of claim 6, wherein the broadcast packet comprises measurements of additional processing delays corresponding to processing associated with communications received from other mobile devices.

8. The method of claim 7, wherein the broadcast packet includes identifiers to identify which measurements of processing delays are associated with specific mobile devices.

9. The method of claim 6, wherein the broadcast packet includes one or more most recently measured processing delays.

10. The method of claim 2, wherein the subsequent communication comprises data transmitted via a data exchange with the first mobile device.

11. The method of claim 1, further comprising measuring a first time difference between transmitting the first communication and receiving the acknowledgement communication, and subtracting the processing delay to determine a second time difference.

12. A wireless device, comprising:

a communication device to wirelessly receive a first communication from a first mobile device; and

a processing unit adapted to;

measure a processing delay; and

generate an acknowledgement communication indicating receipt of the first communication.

13. The wireless device of claim 12, further comprising a transmitter to transmit a subsequent communication comprising a measurement of the processing delay in response to receiving a second communication having a request for the measurement of the processing delay.

14. The wireless device of claim 13, wherein the measurement of the processing delay comprises a most recently measured time interval.

15. The wireless device of claim 13, wherein the measurement of the processing delay comprises a measured time interval and a timestamp at which the processing delay was measured.

17. The wireless device of claim 12, wherein the wireless device further comprises a memory.

18. The wireless device of claim 13, wherein the transmitter is adapted to transmit a measurement of the processing delay in a broadcast packet.

19. The wireless device of claim 18, wherein the transmitter is adapted to transmit, in the broadcast packet, measurements of additional processing delays corresponding to processing associated with communications received from other mobile devices.

20. The wireless device of claim 19, wherein the transmitter is adapted to transmit, in the broadcast packet, identifiers to identify which measurements of processing delays are associated with specific mobile devices.

21. The wireless device of claim 18, wherein the transmitter is adapted to transmit, in the broadcast packet, one or more most recently measured processing delays.

22. The wireless device of claim 12, wherein the wireless device has a substantially fixed position.

23. The wireless device of claim 12, further comprising a clock to indicate a time measurement.

24. The wireless device of claim 12, wherein the wireless device comprises an access point.

25. The wireless device of claim 12, wherein the wireless device comprises a femtocell.

16. The wireless device of 12, wherein the receiver is adapted to receive at least one of the first communication and the second communication as a packet-based communication.

26. An apparatus, comprising:

means for wirelessly receiving a first communication from a first mobile device;

means for measuring a processing delay; and

means for generating an acknowledgement communication indicating receipt of the first communication.

27. The apparatus of claim 26, further comprising means for transmitting a subsequent communication comprising a measurement of the processing delay in response to receiving a second communication having a request for the measurement of the processing delay.

28. The apparatus of claim 27, wherein the measurement of the processing delay comprises a most recently measured time interval.

29. The apparatus of claim 27, wherein the measurement of the processing delay comprises a measured time interval and a timestamp at which the processing delay was measured.

30. The apparatus of claim 27, wherein at least one of the first communication and the second communication comprises a packet-based communication.

31. The apparatus of claim 27, wherein the means for transmitting is adapted to transmit the measurement of the processing delay in a broadcast packet.

32. The apparatus of claim 31, wherein the means for transmitting is adapted to transmit, in the broadcast packet, measurements of additional processing delays corresponding to processing associated with communications received from other mobile devices.

33. The apparatus of claim 32, wherein the means for transmitting is adapted to transmit, in the broadcast packet, identifiers to identify which measurements of processing delays are associated with specific mobile devices.

34. The apparatus of claim 31, wherein the means for transmitting is adapted to transmit, in the broadcast packet, one or more most recently measured processing delays.

35. The apparatus of claim 26, further comprising time measurement means to indicate a measurement of a time interval.

36. The apparatus of claim 26, wherein the apparatus comprises an access point.

37. The apparatus of claim 26, wherein the apparatus comprises a femtocell.

38. An computer-readable medium encoded with instructions which, when executed by a special purpose apparatus, are adapted to direct the special purpose apparatus to perform operations, the instructions comprising:

code to wirelessly receive a first communication from a first mobile device;

code to measure a processing delay; and

code to generate an acknowledgement communication indicating receipt of the first communication.

39. The computer-readable medium of claim 38, the instructions further comprising code to transmit a subsequent communication comprising a measurement of the processing delay in response to receiving a second communication having a request for the processing delay.

40. The computer-readable medium of claim 39, the instructions further comprising code to transmit at least one of the first communication and the second communication as a packet-based communication.

41. The computer-readable medium of claim 38, the instructions further comprising code to transmit a measurement of the processing delay in a broadcast packet.

42. The computer-readable medium of claim 41, the instructions further comprising code to transmit, in the broadcast packet, measurements of additional processing delays corresponding to processing associated with communications received from other mobile devices.

43. The computer-readable medium of claim 42, the instructions further comprising code to transmit, in the broadcast packet, identifiers to identify which measurements of processing delays are associated with specific mobile devices.

44. The computer-readable medium of claim 41, the instructions further comprising code to transmit, in the broadcast packet, one or more most recently measured processing delays.

45. A mobile device, comprising:

a transmitter to wirelessly transmit a first communication to a wireless device, and a second communication comprising a request for a measurement of a processing delay; and

a receiver to receive an acknowledgement communication from the wireless device, and a third communication, from the wireless device, indicating the measurement of the processing delay, associated with generating the acknowledgement communication indicating receipt of the first communication.

46. The mobile device of claim 45, further comprising a processing unit adapted to:

measure a time difference between when the first communication is wirelessly transmitted and when the acknowledgement communication is received; and

subtract the measurement of the processing delay.

47. The mobile device of claim 45, wherein the wireless device comprises an access point.

48. The mobile device of claim 45, wherein the wireless device comprises a femtocell.

49. The mobile device of claim 45, further comprising a clock to indicate a time measurement.