Abstract:In the downlink Multiuser Multiple Input Multiple Output (MU-MIMO) system with limited feedback, the system performance will become interference power limited in the high SNR regime. In this paper an improved PU2RC multi-mode transmission scheme is proposed. Channel Quantization Quality Indicator is feedback to the BS and the corresponding mode selection method is provided. Simulation shows that in practical system with small number of active users, the proposed scheme can adaptively choose the best transmission mode to maximize the sum rate of the system. With identical amount of feedback bits the proposed multi-mode transmission scheme outperforms the traditional PU2RC scheme and provides better reference for application of practical MU-MIMO systems.