Low Complexity Beamfoming Algorithm for Multiuser MIMO Systems

In order to reduce the inter-user interference in multi-user Multiple-Input Multiple-Output (MIMO) wireless communication systems, e.g., MIMO-Orthogonal Frequency Division Multiplexing (MIMO-OFDM) systems, it is often desirable to the complex pre-processing at the transmitter. In this paper, we propose a multi-user beamfoming algorithm with sub-codebook selection. Based on the minimal leakage criterion, the codebook selection, limited feed-forward and MMSE detection are combined in the proposed algorithm. This avoids the complex channel matrix decomposition and inversion. Consequently, the computational complexity at the transmitter is significantly reduced. Simulation results show that the proposed algorithm performs better than existing beamforming algorithms.