Weighted Sum Transmit Power Minimization for Full-Duplex System with SWIPT and Self-Energy Recycling

This correspondence considers a full-duplex (FD) point-to-point system consisting of one multi-antenna full-duplex access point (FD-AP) and one two-antenna full-duplex mobile station (FD-MS). We adopt simultaneous wireless information and power transfer (SWIPT) scheme and apply the self-energy recycling at FD-MS. In order to minimize the weighted sum transmit power, we jointly design the transmit beamforming vector of FD-AP, the receive power splitting (PS) ratio of FD-MS, as well as the transmit power value of FD-MS. Since the original problem is non-convex, we apply semidefinite relaxation (SDR) and obtain a new convex problem. We further prove that both problems have exactly the same solutions. Finally, simulations are provided to verify our analysis, and the comparison with a half-duplex (HD) system demonstrates the significant performance gain from self-energy recycling.