Patent ID: 8385433

Claim:
A method for generating feedback for linear precoding based upon a transmit covariance, the method being performed by a communications apparatus, the method comprising: determining the transmit covariance from observation of a forward link channel; estimating the forward link channel to yield a channel estimate; using a codebook modifier for modifying a predefined codebook based upon the transmit covariance, wherein a disparate communications apparatus maintains a codebook that is substantially similar to the predefined codebook, wherein modifications made to the disparate communications apparatus' codebook are substantially similar to modifications made to the predefined codebook by the communications apparatus, and wherein the predefined codebook comprises at least one matrix having a dimension that is a rank of the forward link channel, wherein the modifying comprises determining a product of a square root of a transmit covariance matrix and an original matrix from the predefined codebook; quantizing the channel estimate by selecting a precoding matrix from the modified predefined codebook; and generating feedback related to the forward link channel by utilizing the modified codebook, wherein the feedback is used for linear precoding.