Power allocation strategy for MIMO broadcast channels with receiver cooperation

For a multiple input multiple output (MIMO) broadcast channel, the receiver-side cooperation could make the system less dependent on the channel state information at the transmitter (CSIT), and thus it is of great significance for practical applications, where the CSIT is usually difficult to perfectly obtain. In order to provide a theoretical guide for the implementation of MIMO broadcast system with receiver cooperation, this paper focuses on the power allocation problem. In the problem, the transmission power is allocated between the transmission downlink and cooperation links among receivers, under the total power constraint. Particularly, the compress-and-forward cooperation strategy is employed. By recasting the problem as a polynomial rooting problem, we finally propose a nearly optimal power allocation strategy. Simulation results show that this strategy leads to negligible loss compared to the exhaustive search method.