Orthogonalization aided distributed scheduling for MU-MIMO BC with adaptive feedback

In this paper, we introduce an orthogonalization aided distributed scheduling algorithm for multiuser MIMO broadcast channels (MU-MIMO BC). In this algorithm each mobile station (MS) selects transmission scheme, including beamforming (BF) and spatial multiplexing (SM) according to its channel state and feeds back channel state information (CSI) adaptively. On receiving CSI from each MS, the base station (BS) activates user subset and an orthogonalization based precoding scheme is applied to eliminate co-channel interference (CCI). The proposed user scheduling algorithm is carried out by MSs and BS corporately. The system feedback load depends on each MS´s channel quality. Compared with existing methods, the proposed scheme can achieve high system capacity as well as better BER performance.