Feedback of channel information in a closed loop beamforming wireless communication system

• US 20060291544A1
• Filed: 04/27/2006
• Published: 12/28/2006
• Est. Priority Date: 06/28/2005
• Status: Active Grant

• Current Assignee: Bell Northern Research, LLC (Hilco Inc. (d/b/a Hilco Global))
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Hansen, Christopher J., Fischer, Matthew J., Trachewsky, Jason A., Kim, Joonsuk
• Granted Patent: US 8,345,732 B2
• Time in Patent Office: Days
• US Class Current: 375/219
• CPC Class Codes: H04B 7/0421 utilizing implicit feedback, e.g. steered pilot signals
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04B 7/0628 Diversity capabilities
• CPC Class Codes: H04B 7/0634 Antenna weights or vector/matrix coefficients
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0045 Arrangements at the receiver end
• CPC Class Codes: H04L 1/0068 by puncturing
• CPC Class Codes: H04L 1/06 using space diversity
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems
• CPC Class Codes: H04W 80/00 Wireless network protocols or protocol adaptations to wireless operation

Abstract

A method for feeding back transmitter beamforming information from a receiving wireless communication device to a transmitting wireless communication device includes a receiving wireless communication device receiving a preamble sequence from the transmitting wireless device. The receiving wireless device estimates a channel response based upon the preamble sequence and then determines an estimated transmitter beamforming unitary matrix based upon the channel response and a receiver beamforming unitary matrix. The receiving wireless device then decomposes the estimated transmitter beamforming unitary matrix to produce the transmitter beamforming information and then wirelessly sends the transmitter beamforming information to the transmitting wireless device.

Claims

1. A wireless communication device operable to transmit an HT-Capability Information Element signal, comprising:

an Element ID field formed to carry a selectable three digit number;

an HT Capabilities Information field;

a MAC HT Parameters Information field; and

a Supported MCS set field.

2. The wireless communication device of claim 1, the signal further including a Length Field for specifying a total frame length.

3. The wireless communication device of claim 1, the signal further including an OUI Field for specifying a specific vendor or vendor parameter.

4. The wireless communication device of claim 1, the signal further including a Type Field for specifying whether an HT element or other type of element is being used.

5. The wireless communication device of claim 1, the signal further including a Beamforming Field for specifying a station'"'"'s capabilities.

6. The wireless communication device of claim 5 wherein at least one of RXBF (capable of receiving beamformed signals), FCHAN (full channel estimate in feedback signal), VCHAN (reduced channel estimate in feedback signal) and TXCAL (calibration for TX link possible based upon feedback signal) may be specified in the Beamforming Field.

7. The wireless communication device of claim 1, the signal further including a Sounding Indicator Field that is operable to signal sounding frame.

8. The wireless communication device of claim 1, the signal further including a Sounding Indicator Field that is operable to signal sounding frame by specifying at least one of a frame not being a sounding frame, a frame having sounding with one more TX antenna (than stream number indicated in MCS), a frame having sounding with two more TX antennas, a frame having sounding with three more TX antennas.

9. The wireless communication device of claim 8, the signal further including an indication that the station is staggered sounding capable.

10. The wireless communication device of claim 8, the signal further including an indication that station is non-staggered sounding capable.

11. The wireless communication device of claim 1, wherein the HT Capabilities Information field indicates whether the station is Receive TxBf capable.

12. The wireless communication device of claim 1 wherein the HT Capabilities Information field indicates at least one of whether the station is Sounding Frame RX capable, Channel Estimate capable or Channel Feedback capable.

13. The wireless communication device of claim 1 wherein the HT Capabilities Information field indicates at least one of whether the station is Sounding Frame RX capable, Channel Estimate capable or V-Matrix Feedback capable.

14. The wireless communication device of claim 1, wherein the HT Capabilities Information field indicates whether the station is Tx Calibration capable.

15. The wireless communication device of claim 1, wherein the HT Capabilities Information field indicates whether the station is Implicit Transmit Beamforming capable.

16. The wireless communication device of claim 1, wherein the HT Capabilities Information field indicates whether the station is Explicit Transmit Beamforming capable and is operable to provide Channel Feedback.

17. The wireless communication device of claim 1, wherein the HT Capabilities Information field indicates whether the station is Explicit Transmit Beamforming capable and is operable to provide V-matrix Feedback.

18. A radio transceiver, comprising:

radio front end circuitry for communicating at a high data rate including circuitry for at least one of transmitting over a plurality of antennas or receiving over a plurality of antennas operable;

wherein the radio front end circuitry is operable to generate a feedback control signal including an HT Control field that includes rate feedback information to a transmitting station on a 802.11 specified frame type by appending the control signal on a variety of 802.11 specified frame types.

19. The radio transceiver of claim 18 wherein a first bit of the feedback control signal is used to indicate that sounding is recommended.

20. The radio transceiver of claim 18, the feedback control signal further including a format for carrying signaling information and for recommending MCS.

21. The radio transceiver of claim 20, wherein the recommended MCS is specified in a seven bit field utilizing a format that is the same as HT-SIG.

22. The radio transceiver of claim 18 wherein the receive station is operable to receive and process an indication generated by a transmit station of whether staggered or non-staggered sounding frames are being used.

23. A method for generating a new sounding frame, comprising:

generating a sounding frame physical format having a LENGTH field set to zero in the HT-SIG field to indicate that the frame is only for sounding.

24. The method of claim 23 for generating a new sounding frame wherein no additional bits are allocated in the HT-SIG field.

25. A radio transceiver, comprising:

radio front end circuitry for communicating at a high data rate including circuitry for at least one of transmitting over a plurality of antennas or receiving over a plurality of antennas operable; and

logic within the radio front end circuitry operable to generate an expanded HT control field.

26. The radio transceiver of claim 25 wherein the radio front end circuitry is operable to generate a new sounding frame having a sounding frame physical format that includes an MCS field set to a specified value in the HT-SIG field to indicate that the frame is only for sounding.

27. The radio transceiver of claim 25 wherein the expanded HT control field includes a link adaptation control portion which further includes a portion for specifying an extension (XT).

28. The radio transceiver of claim 27 wherein the extension is a one bit field.

29. The radio transceiver of claim 27 wherein the link adaptation control portion further includes a portion for specifying a request for sounding.

30. The radio transceiver of claim 29 wherein the request for sounding is a one bit field.

31. The radio transceiver of claim 27 wherein the link adaptation control portion further includes a portion for requesting feedback.

32. The radio transceiver of claim 27 wherein the link adaptation control portion further includes a portion for specifying an MRQ sequence number.

33. The radio transceiver of claim 27 wherein the extension is a three bit field.

34. The radio transceiver of claim 27 wherein the link adaptation control portion further includes a portion for specifying an MCS feedback sequence number.

35. The radio transceiver of claim 34 wherein the portion is a three bit field.

36. The radio transceiver of claim 27 wherein the link adaptation control portion further includes a portion for specifying MCS feedback.

37. The radio transceiver of claim 36 wherein the portion is a seven bit field.

38. The radio transceiver of claim 37 wherein the seven bit field is used to carry a specified number to indicate no feedback.