Sum rate maximization for full duplex wireless-powered communication networks

Abstract

We consider a full duplex multiuser multiple-input multiple-output system and study the sum rate maximization in a wireless powered communication networks. We assume that the users of uplink (UL) channel have no available power supply and thus a harvest-then-transmit protocol is utilized. Specifically, the base station (BS) first conveys simultaneously the energy to all UL users via energy beamforming and also transmit the information to all users in the downlink (DL) channel via information beamforming. Then, the users in the UL channel send their independent information to the BS using their harvested energy in the second phase. Since the utility function of the sum rate maximization is nonconvex, and thus, the optimal solution is difficult to find in general. To solve this problem, we propose an iterative algorithm to obtain suboptimal solution based on semidefinite program in each iteration. Simulation results demonstrate that the proposed design outperforms the conventional design.