On the Energy-Efficient Power Allocation for Amplify-and-Forward Two-Way Relay Networks

This paper addresses power allocation issues for amplify-and-forward (AF) two-way relay systems. Based on theoretical derivation, we first propose an energy-efficient power allocation (PA) strategy for 2-phase and 3-phase two-way systems with single relay or multi-relay, under a certain transmission data rate of source nodes, aiming to minimize the system energy consumption. Numerical results show that this energy-efficient PA strategy can balance the system performance and achieve about 3dBw power gains compared to the uniform PA.