An Adaptive User Selection Algorithm for Multiuser MISO Downlink Systems

Multiuser multi-input single-output (MISO) downlink systems, where one base station equipped with multiple antennas serves multiple single antenna mobile users, is of great interest recently. Significant capacity benefit can be obtained without extra time slots or spectrum. However, the number of simultaneously supportable users is limited by the number of transmit antennas. User selection is required for choosing the best subset in case of more users than transmit antennas. In this paper, we propose an efficient user selection algorithm aiming to maximize the sum rate capacity. The number of selected users can change adaptively according to current channel condition. Through simulation results, the very good performance of the proposed algorithm is shown, and it achieves near optimal performance while with low computational complexity.