Adaptive Relaying Protocol for Wireless Power Transfer and Information Processing

In this letter, an amplify-and-forward (AF) relaying system is considered, where an energy constrained relay node harvests energy from the received radio frequency signal and uses this harvested energy to AF the source signal to the destination. Based on the time switching (TS) and power splitting (PS) receiver architectures, an adaptive receiving architecture for energy harvesting and information processing is proposed and an adaptive relaying (AR) protocol based on it is developed to enable energy harvesting and information processing at the relay. In light of this, analytical expressions of throughput are derived for both delay-limited transmission and delay-tolerant transmission modes, when the AR protocol is implemented at the relay. Monte Carlo simulations are provided throughout to validate our analysis and the impact of some important system parameters on the adopted performance metric are investigated. In addition, we compare the system performance in terms of the throughput of AR protocol with PS relaying and TS relaying protocols proposed by Nasir et al. Results show that, the AR protocol has a better system performance around the point in which there is a throughput crossover for both PS relaying and TS relaying protocols.