Exploiting receive antenna heterogeneity of downlink multiuser-MIMO in wireless networks

A user scheduling problem for downlink multiuser-multiple-input-multiple-output (MU-MIMO) systems is investigated. Unlike in theoretical analysis, users are usually equipped with different numbers of antennas in practical downlink systems, which we call receive antenna heterogeneity. We propose a scheduling algorithm which utilizes the property of receiver antenna heterogeneity to improve the system's throughput. The algorithm consists of two strategies: (1) divide the whole set of users into several groups where each group contains multiple users served simultaneously; (2) allocate spatial streams to users in each group such that sum rate is maximized. Simulation results are provided to show that our algorithm outperforms the homogeneous scheduling algorithm which does not take the heterogeneity into account.