User scheduling scheme for network MIMO system with feedback reduction

In this paper, we propose a new user scheduling scheme which can reduce the system feedback significantly for the MIMO downlink system in multiuser cellular networks. The proposed scheme first performs user scheduling according to the valuebook-based scalar feedback of all users´ channel gains and then applies block diagonalization (BD) precoding according to the codebook-based matrix feedback of the selected users´ channel matrices. A novel method to generate the valuebook is designed. The proposed user scheduling scheme can reduce both the multiuser interference and the feedback bits with low computational complexity. It can be observed from the simulation results that, in the interference-limited SNR regime, the proposed scheme can achieve a sum rate very close to the case when the coordinated base stations know the channel state information perfectly.