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

This paper considers a full-duplex (FD) point-to-point system consisting of one multi-antenna FD access point (FD-AP) and one two-antenna FD mobile station (FD-MS). We adopt simultaneous wireless information and power transfer 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 ratio of FD-MS, and the transmit power value of FD-MS. Since the original problem is non-convex, we apply semidefinite relaxation 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 system demonstrates the significant performance gain from self-energy recycling.