A Limited Feedback-Based Block Diagonalization Scheme for Multi-User MIMO-OFDM Systems

Block diagonalization (BD) is a linear preceding technique for the multi-user MIMO-OFDM systems that involves transmission of multiple data streams to each receiver such that no multi-user interference is experienced at any of the receivers. With perfect channel knowledge at the transmitter, BD can eliminate other users´ interference at each receiver. But it is not practical for receiver to feedback the perfect CSIT to transmitter. In order to reduce the feedback overhead, a novel limited feedback and non-codebook based block diagonalization (LFNCBD) scheme is proposed in this paper. Simulation results show that the proposed scheme could achieve the asymptotical optimal BD sum-capacity performance with limited feedback overhead.