Method and apparatus for reporting channel state information of multi-channel in wireless local area network system

• US 9,088,393 B2
• Filed: 07/29/2011
• Issued: 07/21/2015
• Est. Priority Date: 07/30/2010
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Seok, Yong Ho
• Primary Examiner(s): Hsu, Alpus H
• Assistant Examiner(s): Thai, Camquyen
• Application Number:
  US13/193,941
• Publication Number:
  US 20120026909A1
• Time in Patent Office: 1,453 Days
• Field of Search: 370/252, 370/328, 370/208, 370/338, 370/254, 370/312, 370/349, 370/390, 455/186.1, 455/67.11, 455/69, 375/366, 375/365
• US Class Current: 1/1
• CPC Class Codes: H04B 7/0417 Feedback systems
• CPC Class Codes: H04B 7/0478 Special codebook structures directed to feedback optimisation
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04B 7/0626 Channel coefficients, e.g. channel state information [CSI]
• CPC Class Codes: H04B 7/0632 Channel quality parameters, e.g. channel quality indicator [CQI]
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0031 Multiple signaling transmission H04L1/1664, F15 take precedence
• CPC Class Codes: H04L 1/0687 Full feedback
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04W 16/28 using beam steering
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic
• CPC Class Codes: H04W 28/06 Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365
• CPC Class Codes: H04W 48/08 Access restriction or access information delivery, e.g. discovery data delivery signalling during connection H04W76/00
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

A method for reporting channel state information (CSI), performed by a beamformee, in a wireless local area network system using multi-channels is provided. The method includes receiving, from a beamformer, an NDP announcement (NDPA) frame announcing that a null data packet (NDP) frame follows the NDPA frame, receiving the NDP frame from the beamformer, estimating a channel from a training symbol of the NDP frame and transmitting to the beamformer a CSI report frame containing a result obtained by estimating the channel, wherein the channel is a multi-channel acquired by aggregating first and second channels which are non-contiguous to each other, and wherein the CSI report frame includes an average signal to noise ratio (SNR) for each space-time stream of the first channel and a steering matrix for each subcarrier of the first channel and an average SNR for each space-time stream of the second channel and a steering matrix for each subcarrier of the second channel.

Claims

1. A method for reporting channel state information (CSI) in a wireless local area network system, the method comprising:

receiving, by a responding station, a null data packet (NDP) announcement frame to initiate a sounding feedback sequence from a requesting station, the NDP announcement frame including a receiver address field and a station information field, the station information field including an association identifier of the responding station expected to prepare a sounding feedback,

wherein the station information field further includes a feedback type indicating whether the sounding feedback from a single station is requested or not, and

wherein the receiver address field indicates an address of the responding station identified by the association identifier when the feedback type indicates that the sounding feedback from the single station is requested;

receiving, by the responding station, an NDP frame from the requesting station after receiving the NDP announcement frame, the NDP frame having at least one training field but no data field; and

transmitting, by the responding station, a CSI report frame to the requesting station, the CSI report frame including CSI report information in a form of angles representing a beamforming feedback matrix that is estimated by the responding station based on the NDP frame,

wherein, if the NDP frame is received via a plurality of contiguous channels, the beamforming feedback matrix is estimated based on all of the plurality of contiguous channels, and

wherein, if the NDP frame is received via at least one of a plurality of non-contiguous channels, the beamforming feedback matrix is estimated based on only one of the plurality of non-contiguous channels.

2. The method of claim 1, wherein the receiver address field indicates a broadcast address when the feedback type indicates that the sounding feedback from the single station is not requested.

3. The method of claim 1, wherein the CSI report frame further includes a channel width field indicating the bandwidth of the transmission channel.

4. An apparatus configured to report channel state information (CSI) in a wireless local area network system, the apparatus comprising:

a processor; and

a memory operatively coupled with the processor and storing instructions that when executed by the processor causes to the apparatus to;

receive a null data packet (NDP) announcement frame to initiate a sounding feedback sequence from a requesting station, the NDP announcement frame including a receiver address field and a station information field, the station information field including an association identifier of the apparatus expected to prepare a sounding feedback,

wherein the station information field further includes a feedback type indicating whether the sounding feedback from a single station is requested or not, and

wherein the receiver address field indicates an address of the apparatus identified by the association identifier when the feedback type indicates that the sounding feedback from the single station is requested; and

receive an NDP frame from the requesting station after receiving the NDP announcement frame, the NDP frame having at least one training field but no data field; and

transmit a CSI report frame to the requesting station, the CSI report frame including CSI report information in a form of angles representing a beamforming feedback matrix that is estimated based on the NDP frame,

wherein, if the NDP frame is received via a plurality of contiguous channels, the beamforming feedback matrix is estimated based on all of the plurality of contiguous channels, and

wherein, if the NDP frame is received via at least one of a plurality of non-contiguous channels, the beamforming feedback matrix is estimated based on only one of the plurality of non-contiguous channels.

5. The apparatus of claim 4, wherein the receiver address field indicates a broadcast address when the feedback type indicates that the sounding feedback from the single station is not requested.

6. The apparatus of claim 4, wherein the CSI report frame further includes a channel width field indicating the bandwidth of the transmission channel.