Maximizing Harvested Energy for Full-Duplex SWIPT System With Power Splitting

In this paper, we consider simultaneous wireless information and power transfer in a full-duplex (FD) communication system consisting of one FD access point A (FD-A) and one FD device B (FD-B), each being equipped with a pair of transmitter-receiver antennas for signal transmission and reception respectively. The power splitting (PS) scheme is adopted at FD-B to receive information and energy concurrently. In order to maximize the energy harvested by FD-B while considering the constraints of signal-to-interference-and-noise ratio (SINR) and maximum transmit power at both nodes, we jointly design the optimal transmit power of FD-A and FD-B, as well as the PS ratio of FD-B. Unfortunately, the primal problem is non-convex and is not always feasible with different parameters. Thus, we first present a set of conditions, under which the feasibility of the primal problem is guaranteed. Then, we derive the closed form of the optimal solution with the aid of analyzing the feasible region of the problem. Furthermore, the influences of the parameters on the maximum harvested energy are theoretically analyzed. Finally, simulation results are provided to verify the optimality of the proposed closed-form solution, to validate the analysis of the impact of parameters on the maximum harvested energy and to show the effectiveness of the proposed design, respectively.