An Efficient Energy Utilization Approach in SWIPT Dual-Relay Cooperative System

Abstract

In this paper, dual-relay simultaneous wireless information and power transfer(SWIPT) cooperative system is considered. Power splitting(PS) is adopted by the off-the-grid relay for energy harvesting(EH) and information processing in the first phase. Next, the harvested energy at the relay is used to forward the signals of the sorce node in the second phase. To enhance the reliability of the system and utilize the energy harvested more efficiently, an energy aware retransmission (EAR) scheme is adopted in the first phase to guarantee that a certain minimum amount of energy is harvested by the relay before launching in the second phase. Then, we analyze the ergodic capacity of the system. Simulation results demonstrate that the EAR scheme is superior than the traditional single transmission scheme and improves the reliability of SWIPT-based cooperative systems and makes energy utilization more efficient.