Patent ID: 9332449
Filing Date: 2016-05-03
CPC Classification: H04B,H04W

Claim Text:
1. A method for transmitting channel state information, comprising: receiving a Null Data Packet Announcement (NDPA) frame including recommended grouping information; receiving a Null Data Packet (NDP) frame; determining Signal-to-Noise Ratio (SNR) information for a first sub-carrier of a spatial stream which has transmitted the NDP frame; and determining a compressed beamforming feedback matrix including channel state information for a second sub-carrier of the spatial stream, wherein each of the first sub-carrier and the second sub-carrier is determined based on the recommended grouping information, and wherein the recommended grouping information includes information related to grouping of a plurality of subcarriers to determine the first sub-carrier and the second sub-carrier, wherein the SNR information is determined based on a variance between a SNR value of the first sub-carrier and an average value of SNR of sub-carriers used to transmit the at least one spatial stream.