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.