A Reduced Feedback Precoder for Cooperative Relay Networks

A new precoder that reduces the feedback overhead in an OFDM-based relay network is proposed. A joint Singular Value Decomposition (SVD) and QR Decomposition is employed at the source-destination link and source-relay-destination link. Using the proposed precoder, only one precoding matrix needs to be fed back, independent of the total number of subcarriers. The link achievable rate using the reduced complexity precoder is evaluated via simulations and compared with that of full SVD precoders and for varying codebook size.