Joint Optimization of Multiple-Relay Amplify-and-Forward Systems Based on Simultaneous Wireless Information and Power Transfer

Simultaneous wireless information and power transfer (SWIPT) is investigated in amplify-and- forward (AF) relay systems. Each relay node facilitates communication between a source node and a destination node. The relay nodes are equipped with radio frequency (RF) energy harvesters to supply power for retransmission of information signals from the source node to the destination node. In this paper, both power splitting (PS) ratio and adaptive power control are jointly optimized for optimal SWIPT multiple- relay systems performance. We demonstrate that the optimal power allocation strategy in joint optimization problem is to use full harvested power. We propose both an optimal centralized PS scheme and a distributed suboptimal scheme suitable for practical implementation. Simulation results demonstrate that the proposed schemes outperform naive PS schemes in terms of the average rate and the bit-error rate.