非再生中继合作下的OFDM系统功率分配研究

ooperative relayed transmission is an efficient way to achieve space-time diversity and to combat wireless channel fading. Optimal power allocation for non-regenerative relaying OFDM system is studied in this paper. Firstly, an equivalent channel gain model is proposed for single pair of cooperative subcarriers, based on which the optimal subcarrier pair selection scheme is given by applying the Hungarian algorithm.Then the optimal power allocation can be obtained either by using water-filling approach or by greedy bit allocation method on the selected subcarrier pairs. Simulation results show that the proposed power allocation algorithm achieves higher power efficiency than both direct transmission and the random cooperative subcarrier pair selection scheme, particularly when the rate requirement is high.