Beamforming Design in Relay-Based Full-Duplex MISO Wireless Powered Communication Networks

Abstract

In this letter, we jointly design the beamformers of relay and source in full-duplex relay-based wireless powered communication networks. Equipped with multiple antennas, the relay/source is designed to transmit information and receive information/energy simultaneously. Furthermore, the hybrid access point (H-AP) acts as relay to assist the information transfer from source to destination. Moreover, source transmits signals only with the energy harvested from H-AP/relay and recycled energy from its own transmitted signals. In this setup, we propose a novel one-phase co-channel protocol and jointly design the beamforming of relay and source to maximize the system throughput. As the problem is non-convex, we first use zero forcing (ZF) method to cancel the self-interference at relay and then propose a low-complexity algorithm to obtain the global optimum when the ZF constraint is assumed. Numerical results show that our proposed optimal beamforming design is superior to other reference schemes.