Patent ID: 8634867

Claim:
A transmitter of a first device in a multi-user multi-antenna communication system, the transmitter comprising: a receiver filter calculating unit configured to calculate receiving beamforming weights for each of a plurality of receivers of second devices; an index determining unit configured to determine a codebook index based on the calculated receiving beamforming weights for each of the plurality of receivers of second devices; and a radio frequency (RF) unit configured to transmit the codebook index for each of the plurality of receivers, wherein the transmitter is configured to transmit the codebook index for each of the plurality of receivers by one of: modulating all pilot subcarriers with the receiving beamforming weights of one of the plurality of receivers and including information related to the receiving beamforming weights for each of the other receivers in each data subcarrier for the other receivers, replacing common pilot subcarriers with dedicated pilot subcarriers and including information related to the receiving beamforming weights for the plurality of receivers in each of data subcarriers for the plurality of receivers, and replacing the data subcarriers with the dedicated pilot subcarriers and including information related to the receiving beamforming weights for the plurality of receivers in each of the data subcarriers for the plurality of receivers.