解码转发中继MIMO系统天线选择的能效分析

Energy-Efficiency Analysis of IDF MIMO System with Relay Antenna Selection

研究的是一个多输入输出(MIMO)中继协作系统,采用自动请求重传(ARQ)协议,中继在收到接收端的否定应答时转发信息。这里关注中继节点的天线选择的问题,考虑了电路功耗,采用了一种新的能效分析方法,并得到系统中断概率和能效的闭式表达式。接着分析了中继天线选择策略和接收节点的相对距离对系统能效的影响。仿真结果表明,在接收节点距离发送节点或中继节点较远的情况下,接收端天线选择策略(SSC)具有明显优势。实际应用中可以在中继预设阈值,以此切换天线选择策略,此结论对于这种方法具有实际的参考价值。

A cooperative incremental decode-and-forward （IDF） MIMO relay system is studied, and with the application of ARQ （ Automatic Repeat Request） protocol, the relay forwards the received signal when receiving NACK （Negative Acknowledgement） from the destination. This paper focuses the attention on the antenna selection of relay node and circuit power. And with a novel energy efficiency analytical framework, the closed-form expressions of outage probability and energy efficiency are derived and then the selection strategies of relay antenna and the effects of relative distance of between the receiving nodes on system energy efficiency also analyzed. Simulation results show that SSC enjoys clear superiority when the destination is relatively far from the source or relay. The pre-setting of calculation thresholds may be done in practical application, thus to switch the antenna selection strategy, and this conclusion is of certain reference value for division of relay AS schemes.