Novel codeword selection strategy for MIMO precoding with limited channel state information feedback

A novel strategy codeword selection (called partial channel precoding) for channel state information (CSI) in a limited feedback scenario is proposed. Consider as an example the CSI codebook in the 3GPP LTE system of a 4times4 MIMO structure. Rather than using the traditional method of selecting the nearest codebook to the right singular vectors of the entire channel matrix, a partial match that aims to place the third and fourth signal streams near the null space of the first two receive antennas is presented. Combined with the successive interference cancellation scheme, this novel codeword selection strategy is shown to improve SINR and subsequently the frame error rate performance of a MIMO-OFDM system.