A Novel Multiuser Beamforming System With Reduced Complexity and Beam Optimizations

Abstract

Analog beamforming is widely used in the incoming 5G/B5C communications systems to leverage against power consumption by significantly reducing the number of RF chains. In this paper, we propose a new multiuser beamforming scheme that allows the number of RF chains to be smaller than the number of users. In addition, we propose the beamforming algorithms to minimize the transmit power and weighted symbol error rates for the proposed scheme. For both high- and low-SNR regimes, the proposed beamforming designs provide simple closed-form solutions. The simulation results show that with half the number of RF chains and, thus, lower hardware cost, the proposed scheme outperforms the conventional zero-forcing beamforming systems in several interested parameter settings. Meanwhile, the performance degradation due to the quantization effect of the proposed system is less pronounced than that of the conventional heamforming systems.