针对采用放大转发和MQAM调制的源-中继-终端的通信链路,研究了在保证终端解调误码率低于给定值条件下调制速率对能量效率的影响.推导了射频电路消耗的最小功率,在考虑电路消耗功率的情况下得到了能效性能的函数表达式.理论分析表明,能效性能是调制速率的拟凹函数,当调制速率增大时,能效先递增再递减.通过仿真计算验证了理论分析的正确性.
The influence of modulation rate on energy efficiency (EE) for a source-relayterminal communication link using the amplify-and-forward (AF) protocol and MQAM is studied given a prescribed error rate (BER). Transmission power consumption is calculated. The total power consumption is obtained when the circuit power consumption is taken into account. An expression of EE is derived, and the influence of modulation rate on EE studied. Simulation results show that, with the modulation rate increasing, energy efficiency increases first, and then decreases.
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