WIRELESS CHANNEL CALIBRATION

• US 20100271992A1
• Filed: 04/22/2010
• Published: 10/28/2010
• Est. Priority Date: 04/23/2009
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Van Zeist, Albert, Wentink, Maarten Menzo
• Granted Patent: US 8,842,587 B2
• Time in Patent Office: Days
• US Class Current: 370/310
• CPC Class Codes: H04B 17/21 for calibration; for correcting measurements
• CPC Class Codes: H04B 7/0617 for beam forming

Abstract

This document describes, among other things, a method that includes transmitting a calibration initiation frame from a first wireless communication device to a second wireless communication device that comprises a single space-time stream transmitter via a wireless communication medium. The method also includes receiving at the first wireless communication device an acknowledgement frame sent from the second wireless communication device after the second wireless communication device receives the calibration initiation frame. The method further includes transmitting a null data packet (NDP) frame from the first wireless communication device to the second wireless communication device after receiving the acknowledgement frame. In some implementations, the method also includes performing beamforming calibration of a wireless communication channel between the first wireless communication device and the second wireless communication device based on the acknowledgement frame.

Claims

1. A method comprising:

transmitting a calibration initiation frame from a first wireless communication device to a second wireless communication device that comprises a single space-time stream transmitter via a wireless communication medium;

receiving at the first wireless communication device an acknowledgement frame sent from the second wireless communication device after the second wireless communication device receives the calibration initiation frame; and

transmitting a null data packet (NDP) frame from the first wireless communication device to the second wireless communication device after receiving the acknowledgement frame.

2. The method of claim 1, further comprising performing beamforming calibration of a wireless communication channel between the first wireless communication device and the second wireless communication device based on the acknowledgement frame.

3. The method of claim 2, further comprising receiving at the first wireless communication device a channel state information (CSI) frame sent from the second wireless communication device, and wherein performing beamforming calibration of the wireless communication channel is also based on the CSI frame.

4. The method of claim 3, wherein the CSI frame comprises a CSI feedback matrix determined by the second wireless communication device based on the NDP frame.

5. The method of claim 1, wherein the calibration initiation frame comprises a request for acknowledgement, an NDP announcement, and a request for channel state information (CSI).

6. The method of claim 5, wherein the calibration initiation frame further comprises a training request (TRQ).

7. The method of claim 1, further comprising receiving at the first wireless communication device a second acknowledgement frame sent from the second wireless communication device after the second wireless communication device receives the NDP frame, and transmitting a calibration complete frame from the first wireless communication device to the second wireless communication device after receiving the second acknowledgement frame.

8. The method of claim 7, further comprising performing beamforming calibration of a wireless communication channel between the first wireless communication device and the second wireless communication device based on the second acknowledgement frame.

9. The method of claim 8, further comprising receiving at the first wireless communication device a channel state information (CSI) frame sent from the second wireless communication device, and wherein performing beamforming calibration of the wireless communication channel is also based on the CSI frame.

10. The method of claim 9, wherein the CSI frame comprises a CSI feedback matrix determined by the second wireless communication device based on the NDP frame.

11. The method of claim 7, wherein the calibration initiation frame comprises a request for acknowledgement and an NDP announcement.

12. The method of claim 7, wherein the calibration complete frame comprises a request for channel state information (CSI).

13. A wireless communication device comprising:

a wireless transmitter configured to transmit a calibration initiation frame to a second wireless communication device that comprises a single space-time stream transmitter via a wireless communication medium; and

a wireless receiver configured to receive an acknowledgement frame sent from the second wireless communication device after the second wireless communication device receives the calibration initiation frame;

wherein the wireless transmitter is further configured to transmit a null data packet (NDP) frame to the second wireless communication device after receiving the acknowledgement frame.

14. The wireless communication device of claim 13, further comprising a calibration module configured to perform beamforming calibration of a wireless communication channel between the wireless communication device and the second wireless communication device based on the acknowledgement frame.

15. The wireless communication device of claim 14, wherein the wireless receiver is further configured to receive a channel state information (CSI) frame sent from the second wireless communication device, and wherein the beamforming calibration is also based on the CSI frame.

16. The wireless communication device of claim 13, wherein the wireless receiver is further configured to receive a second acknowledgement frame sent from the second wireless communication device after the second wireless communication device receives the NDP frame, and wherein the wireless transmitter is further configured to transmit a calibration complete frame to the second wireless communication device after receiving the second acknowledgement frame.

17. The wireless communication device of claim 16, further comprising a calibration module configured to perform beamforming calibration of a wireless communication channel between the wireless communication device and the second wireless communication device based on the second acknowledgement frame.

18. The wireless communication device of claim 17, wherein the wireless receiver is further configured to receive a channel state information (CSI) frame sent from the second wireless communication device, and wherein the beamforming calibration is also based on the CSI frame.

19. A wireless communication device comprising:

means for transmitting a calibration initiation frame to a second wireless communication device that comprises a single space-time stream transmitter via a wireless communication medium;

means for receiving an acknowledgement frame sent from the second wireless communication device after the second wireless communication device receives the calibration initiation frame; and

means for transmitting a null data packet (NDP) frame to the second wireless communication device after receiving the acknowledgement frame.

20. The wireless communication device of claim 19, further comprising means for performing beamforming calibration of a wireless communication channel between the wireless communication device and the second wireless communication device based on the acknowledgement frame.

21. The wireless communication device of claim 20, further comprising means for receiving a channel state information (CSI) frame sent from the second wireless communication device, and wherein performing beamforming calibration of the wireless communication channel is also based on the CSI frame.

22. The wireless communication device of claim 19, further comprising means for receiving a second acknowledgement frame sent from the second wireless communication device after the second wireless communication device receives the NDP frame, and means for transmitting a calibration complete frame to the second wireless communication device after receiving the second acknowledgement frame.

23. The wireless communication device of claim 22, further comprising means for performing beamforming calibration of a wireless communication channel between the wireless communication device and the second wireless communication device based on the second acknowledgement frame.

24. The wireless communication device of claim 23, further comprising means for receiving a channel state information (CSI) frame sent from the second wireless communication device, and wherein performing beamforming calibration of the wireless communication channel is also based on the CSI frame.

25. A computer-readable storage medium comprising instructions that, upon execution, cause a processor to:

transmit a calibration initiation frame from a first wireless communication device to a second wireless communication device that comprises a single space-time stream transmitter via a wireless communication medium;

receive at the first wireless communication device an acknowledgement frame sent from the second wireless communication device after the second wireless communication device receives the calibration initiation frame; and

transmit a null data packet (NDP) frame from the first wireless communication device to the second wireless communication device after receiving the acknowledgement frame.

26. The computer-readable storage medium of claim 25, further comprising instructions that cause a processor to perform beamforming calibration of a wireless communication channel between the first wireless communication device and the second wireless communication device based on the acknowledgement frame.

27. The computer-readable storage medium of claim 26, further comprising instructions that cause a processor to receive at the first wireless communication device a channel state information (CSI) frame sent from the second wireless communication device, and wherein performing beamforming calibration of the wireless communication channel is also based on the CSI frame.

28. The computer-readable storage medium of claim 25, further comprising instructions that cause a processor to receive at the first wireless communication device a second acknowledgement frame sent from the second wireless communication device after the second wireless communication device receives the NDP frame, and transmit a calibration complete frame from the first wireless communication device to the second wireless communication device after receiving the second acknowledgement frame.

29. The computer-readable storage medium of claim 28, further comprising instructions that cause a processor to perform beamforming calibration of a wireless communication channel between the first wireless communication device and the second wireless communication device based on the second acknowledgement frame.

30. The computer-readable storage medium of claim 29, further comprising instructions that cause a processor to receive at the first wireless communication device a channel state information (CSI) frame sent from the second wireless communication device, and wherein performing beamforming calibration of the wireless communication channel is also based on the CSI frame.

31. A method comprising:

receiving, at a first wireless communication device that comprises a single space-time stream transmitter, a calibration initiation frame transmitted from a second wireless communication device via a wireless communication medium;

transmitting to the second wireless communication device an acknowledgement frame after receiving the calibration initiation frame; and

receiving a null data packet (NDP) frame from the second wireless communication device sent after the second wireless communication device receives the acknowledgement frame.

32. The method of claim 31, further comprising determining a channel state information (CSI) feedback matrix based on the NDP frame, and transmitting to the second wireless communication device a CSI frame that comprises the determined CSI feedback matrix.

33. The method of claim 31, further comprising transmitting to the second wireless communication device a second acknowledgement frame after receiving the NDP frame, and receiving a calibration complete frame from the second wireless communication device sent after the second wireless communication device receives the second acknowledgement frame.

34. The method of claim 33, further comprising determining a channel state information (CSI) feedback matrix based on the NDP frame, and transmitting to the second wireless communication device a CSI frame that comprises the determined CSI feedback matrix.

35. A wireless communication device comprising:

a wireless receiver configured to receive a calibration initiation frame transmitted from a second wireless communication device via a wireless communication medium; and

a wireless transmitter configured to transmit to the second wireless communication device an acknowledgement frame after receiving the calibration initiation frame;

wherein the wireless receiver is further configured to receive a null data packet (NDP) frame from the second wireless communication device sent after the second wireless communication device receives the acknowledgement frame, and wherein the wireless communication device comprises a single space-time stream transmitter.

36. The wireless communication device of claim 35, further comprising a calibration module to determine a channel state information (CSI) feedback matrix based on the NDP frame, and wherein the wireless transmitter is further configured to transmit to the second wireless communication device a CSI frame that comprises the determined CSI feedback matrix.

37. The wireless communication device of claim 35, wherein the wireless transmitter is further configured to transmit to the second wireless communication device a second acknowledgement frame after receiving the NDP frame, and wherein the wireless receiver is further configured to receive a calibration complete frame from the second wireless communication device sent after the second wireless communication device receives the second acknowledgement frame.

38. The wireless communication device of claim 37, further comprising a calibration module to determine a channel state information (CSI) feedback matrix based on the NDP frame, and wherein the wireless transmitter is further configure to transmit to the second wireless communication device a CSI frame that comprises the determined CSI feedback matrix.

39. A method comprising:

transmitting a calibration initiation frame from a first wireless communication device to a second wireless communication device that comprises a single space-time stream transmitter via a wireless communication medium;

transmitting a null data packet (NDP) frame from the first wireless communication device to the second wireless communication device after transmitting the calibration initiation frame;

receiving at the first wireless communication device an acknowledgement frame sent from the second wireless communication device after the second wireless communication device receives the NDP frame; and

transmitting a calibration complete frame from the first wireless communication device to the second wireless communication device after receiving the acknowledgement frame.

40. The method of claim 39, further comprising performing beamforming calibration of a wireless communication channel between the first wireless communication device and the second wireless communication device based on the acknowledgement frame.

41. The method of claim 40, further comprising receiving at the first wireless communication device a channel state information (CSI) frame sent from the second wireless communication device, and wherein performing beamforming calibration of the wireless communication channel is also based on the CSI frame.

42. The method of claim 41, wherein the CSI frame comprises a CSI feedback matrix determined by the second wireless communication device based on the NDP frame.

43. The method of claim 39, wherein the calibration initiation frame comprises an NDP announcement.

44. The method of claim 39, wherein the calibration complete frame comprises a request for channel state information (CSI).

45. A wireless communication device comprising:

a wireless transmitter configured to transmit a calibration initiation frame to a second wireless communication device that comprises a single space-time stream transmitter via a wireless communication medium, and to transmit a null data packet (NDP) frame to the second wireless communication device after transmitting the calibration initiation frame; and

a wireless receiver configured to receive an acknowledgement frame sent from the second wireless communication device after the second wireless communication device receives the NDP frame;

wherein the wireless transmitter is further configured to transmit a calibration complete frame to the second wireless communication device after receiving the acknowledgement frame.

46. The wireless communication device of claim 45, further comprising a calibration module configured to perform beamforming calibration of a wireless communication channel between the wireless communication device and the second wireless communication device based on the acknowledgement frame.

47. The wireless communication device of claim 46, wherein the wireless receiver is further configured to receive a channel state information (CSI) frame sent from the second wireless communication device, and wherein performing beamforming calibration of the wireless communication channel is also based on the CSI frame.

48. A method comprising:

receiving, at a first wireless communication device that comprises a single space-time stream transmitter, a calibration initiation frame transmitted from a second wireless communication device via a wireless communication medium;

receiving a null data packet (NDP) frame from the second wireless communication device sent after the second wireless communication device transmits the calibration initiation frame;

transmitting to the second wireless communication device an acknowledgement frame after receiving the NDP frame; and

receiving a calibration complete frame from the second wireless communication device sent after the second wireless communication device receives the acknowledgement frame.

49. The method of claim 48, further comprising determining a channel state information (CSI) feedback matrix based on the NDP frame, and transmitting to the second wireless communication device a CSI frame that comprises the determined CSI feedback matrix.