Optimal Secrecy Throughput and Efficient Energy Harvesting for SWIPT System

In recent years, simultaneous wireless information and power transfer (SWIPT) has attracted people's research interest, but many researchers only consider one of the secrecy throughput and harvested energy. In this paper, we optimize the secrecy throughput and improve the utilization of the harvested energy in a certain way with a based beamforming artificial noise aided SWIPT system over a Rayleigh fading channel. We investigate the relationship between the secrecy outage probability and the target secrecy rate and the power allocation ratio through formula derivation and simulation results. Then we propose an algorithm of joint power allocation and splitting to achieve the maximum secrecy throughput. Furthermore, we investigate the maximum secrecy throughput in the beamforming mode and that in broadcast mode. The simulation results show that the use of beamforming technique can greatly improve the performance of the secrecy throughput and the harvested energy.