Wireless Power Transfer Strategies for Cooperative Relay System to Maximize Information Throughput

In this paper, wireless power transfer (WPT) strategies to maximize information throughput are studied for cooperative relay systems, where the relay has to harvest energy from radio frequency signals in order to help the source transmit information to the destination. First, the performances of three basic WPT schemes, source WPT, destination WPT, and joint source and destination WPT, is analyzed. Then, for a given transmission duration, optimal transfer parameters to maximize system information throughput for these three WPT schemes are provided. With the distances from the source and destination to the relay, we propose an optimal WPT strategy and two suboptimal WPT strategies. Finally, simulation results verify the theoretical results and show that there is no one WPT scheme always achieving the best performance at various relay positions. Moreover, it is also presented that the proposed optimal WPT strategy outperforms both suboptimal strategies.