On the performance of multiuser MIMO systems in Beyond 3G: beamforming, feedback and scheduling

In WCDMA/HSDPA of 3GPP, several multiple-input multiple-output (MIMO) techniques have been proposed and in progress of performance evaluation for comparison. Most MIMO candidates in HSDPA have been generally designed based on a point-to-point communication, which means that a single-user capacity is of major concern. However, multiple users and user scheduling need to be considered for wireless packet transmission in beyond 3G, so as to maximize system throughput. In this paper we propose the multiuser MIMO scheme with the effective user scheduling technique in both space and time domains accompanying three main features, which are the spatial-beamforming, uplink feedback signaling, and user scheduling. We also investigate the impact of feedback signaling. Simulation results show that the proposed scheme has higher user diversity gain than other MIMO candidates in terms of ergodic capacity.