Patent ID: 7629902

Claim:
A method for communication, the method comprising the steps of: generating a codebook comprising a first set of codewords and a second set of codewords, with each one of the first set of codewords being a constant modulus matrix, and each one of the second set of codewords being a non-constant modulus matrix; establishing a mapping scheme from the codewords in the first set of codewords to the codewords in the second set of codewords; transmitting, via a first node to a second node, information regarding a first codeword selected from the codebook in dependence upon a condition of a transmission channel between first node and the second node in a multiple input multiple output communication system; determining, at the second node, whether the first codeword selected by the first node is a constant modulus matrix or a non-constant modulus matrix; and when the second node determines that the first codeword selected by the first node is a non-constant modulus matrix, replacing, by the second node, the first codeword with a second codeword that is selected from the first set of codewords and that corresponds to the first codeword in accordance with the mapping scheme established.