Combined Beamforming and Scheduling for High Speed Downlink Packet Access

Joint operation of High Speed Downlink Packet Access (HSDPA) and adaptive antennas in a WCDMA cellular network is considered. The total throughput per cell of HSDPA depends heavily on the strategy employed by the scheduler. It is argued that the maximum SIR scheduler, which maximizes throughput in the single antenna system by serving only the user with best momentary channel quality, will not substantially benefit from adaptive antennas due to excess self interference at the receiver. As an alternative a set of scheduling strategies is proposed, which rely on serving simultaneously multiple spatially separated users. System level simulations show that with the Spatial Division Multiple Access scheduler it is possible to achieve almost twofold throughput improvement over maximum SIR when using four antennas per sector.