Adaptive Proportional Fair Scheduling Based on Opportunistic Beamforming for MIMO Systems

In MIMO systems, the multi-user diversity is exploited by always scheduling the subscribers whose channel conditions are almost in their peaks. The throughput of system is increased but the fairness is ignored, even some subscribers will be "starvation". In this paper, the fairness of the MIMO systems is concerned and two adaptive proportional fair scheduling schemes based on opportunistic beamforming are proposed to increase the throughput of the subscribers in the bad channel conditions and guarantee the fairness allover the systems. In each timeslot, the adaptive parameters are updated by monitoring the requested data rate and the mean of the requested data rate in the past period. And the adaptive parameters are updated per-user basis. The proposed schemes find a tradeoff between the throughput and the fairness. And the simulation results show the validity.