Fast iterative user selection for multiuser MIMO system

In a downlink multiuser multi-input multi-output (MU-MIMO) communication system, a base station (BS) transmits to multiple mobile stations (MS) simultaneously over the same frequency band, thereby greatly increasing the channel capacity. However, in previous works, the multiuser spatial multiplexing system has no special strategies for selecting the multiuser channel. Although the exhaustive search algorithm can achieve optimal performance, its cost is large. In this paper, we propose a suboptimal user selection algorithm for the MU-MIMO system to save hardware resources and serve more users. The proposed selecting criterion bases on maximum total throughput by selecting the best channel of user. To reduce the complexity further more, we give out an iterative selection scheme. Compared with the optimal algorithm, the proposed algorithm achieves good sum capacity performance, has lower complexity, and is suitable for practical communication system. Simulation results show the performance of the proposed scheme.