Patent ID: 8804612

Claim:
A method for determining when a beamforming matrix is updated in a wireless communications system, the wireless communications system including a beamformer and a beamformee, the method comprising: in the beamformer, determining channel estimates based on predetermined signals from the beamformee, the predetermined signals including channel state information, a beamforming matrix, or a compressed beamforming matrix; determining whether an antenna configuration at the beamformer has changed; determining whether a channel between the beamformer and the beamformee has changed based on a correlation of a stored channel estimate and a current channel estimate; and determining whether the beamformer has received an advance notice from the beamformee, wherein when the antenna configuration at the beamformer has not changed, the channel has not changed as determined by the correlation not being less than a correlation threshold, and the beamformer has not received advance notice, then the beamformer continues determining channel estimates based on the predetermined signals from the beamformee, and wherein when at least one of the antenna configuration at the beamformer has changed, the channel has changed as determined by the correlation being less than the correlation threshold, and the beamformer has received advance notice, then the beamformer triggers an update of the beamforming matrix.