Influence of Modulation Rate on Energy Efficiency for Relay-aided Transmission: Amplify-and-forward Protocol
Fangfang Chen, Tao Wang, Xuping Zhai, Yanzan Sun · 2016
This paper describes a general relay system on the condition of a given bit-error-rate(BER).The message bits are transmitted with the assistance of a relay node using one-way amplify-and-forward(AF) relaying protocols, and the effect of modulation rate on energy efficiency (EE) is studied.First, we calculate the transmission power consumption, then the total power consumption can be obtained when circuit power consumption is taken into account.Finally, the expression of EE is derived.The theoretical analysis shows that the energy efficiency is the quasiconcave function of the modulation rate.Through the simulation results we know that when the modulation rate increases, the energy efficiency first increases and then decreases.