Adaptive comp downlink transmission mode selection in backhaul-constrained cellular systems

CoMP has been adopted in 3GPP LTE-Advanced to improve the coverage of high data rates. And the downlink transmission mode, JP or CB, should be selected for base station cooperation when the backhaul capacity is limited. In this paper, considering different numbers of users, we propose an adaptive transmission mode selection. To mitigate the performance degradation caused by mismatching between numbers of transmitting antennas and MSs, we develop a strategy with proportional fairness that takes into account backhaul constraints and users selection. The simulation results show that the proposed algorithm provide considerable performance gains in the sum rates per cell and the cell-edge user throughput under constrained-capacity backhaul links.