Patent ID: 8315204

Claim:
A method comprising: determining, by a mobile station, a channel matrix that is representative of conditions of a channel between a base station and the mobile station over a first time period; determining, by the mobile station, a channel covariance matrix from the channel matrix, wherein the channel covariance matrix is representative of conditions of the channel over a second time period that is longer than the first time period; determining, by the mobile station, a beamforming matrix based at least in part on the determined channel covariance matrix; selecting, by the mobile station, a quantized beamforming matrix from a first plurality of candidate matrices included in a first codebook, wherein the quantized beamforming matrix is representative of the beamforming matrix; determining, by the mobile station, a difference matrix that is representative of a difference between the beamforming matrix and the quantized beamforming matrix; selecting, by the mobile station, a quantized difference matrix from a second plurality of candidate matrices included in a second codebook, wherein the quantized difference matrix is representative of the difference matrix; and transmitting, by the mobile station to the base station, a first codeword and a second codeword associated with the quantized beamforming matrix and the quantized difference matrix, respectively.