中文摘要：

基于瑞利衰落的单源单宿多中继译码转发（Decode—and—Forward，DF）协作系统，提出了一种联合功率分配和自适应多电平正交幅度调制（MQuadratureAmplitudeModulation，M—QAM）算法．推导出了在高信噪比下系统误符号率（Symbolerrorratio，SER）的紧密上界闭式表达式，并在给定系统SER的条件下，得到最小化SER的功率次优分配和实现M—QAM自适应速率控制的联合算法．该联合算法仅需要在发送端获得信道统计状态信息（ChannelStatisticStateIn—formation，CSSI），从而避免了系统信道瞬时状态信息交互的开销．实验仿真表明，在高信噪比下，推导的闭式表达式逼近蒙特卡罗实验结果，提出的联合算法带来了性能增益．

英文摘要：

In a decode-and-forward Rayleigh fading system with relay nodes, this paper derived a tight up- per bound on symbol error rate （SER） in the high signal-to-noise ratio （SNR） regime, and then proposed a joint power allocation and adaptive M-QAM algorithm. The algorithm requires transmission nodes to have only the channel statistic state information （CSSI）, with channel instantaneous state information （CISI）. bound approximates the Monte Carlo results and the which spends fewer overheads than power schemes The simulation results show that the derived upper proposed algorithm achieves performance gain.