Uplink Spatial Scheduling with Adaptive Transmit Beamforming in Multiuser MIMO Systems

Abstract

This paper presents uplink spatial scheduling with adaptive transmit beamforming, where terminals perform system-based transmit beamforming in multiuser multi-input multi-output (MIMO) systems. In the presented spatial scheduling, the base station (BS) selects appropriate combination of terminals and their transmit beamforming among possible terminals. In the selection process, a terminal and its transmit beamforming for a signal are successively selected, considering the effect of the other predetermined signals. In performance evaluation, we show that the spatial scheduling achieves much larger system throughput than the system without spatial scheduling. We also present a basic system configuration in which the BS reports the target transmit beamforming to the selected terminal efficiently in time-division duplex (TDD) system downlink