Robust joint beamforming for MIMO Broadcast system with limited feedback

In Multiple-In Multiple-Out (MIMO) Broadcast systems with limited feedback, when receivers are equipped with multiple antennas, the so-called quantization error of channel direction matrix was unavoidably introduced. This quantization error will result in the reduction of system capacity since it was referenced in the beamforming design. In this paper, we proposed a robust beamforming method based on MMSE, which considers the statistical characteristics of the quantization error for channel direction matrix. Simulation results show that the proposed method effectively enhanced system capacity, reduced bit error rate (BER), as well as mitigated the Plateau Effect.