Optimal scheme for simultaneous wireless information and power transfer to maximize weighted sum rate in full-duplex systems

Abstract

Aimed at resolving the existing problems of simultaneous wireless information and power transfer (SWIPT) schemes in full duplex wireless systems, this paper proposes an optimal scheme based on weighted sum rate (WSR) maximization in multiuser full-duplex systems. In contrast to the traditional scheme, both the access point and users in the scheme work in FD mode, and the downlink channel implements SWIPT. Additionally, the receiver considers self-interference signals and mutual interference signals as usable RF signals to harvest energy. Therefore, we have designed a joint optimization scheme for timeslot distribution factor and power splitting factor to maximize WSR. We derive the optimal solution closed form expression of the timeslot distribution factor by using equivalent conditions and the Lagrangian multiplier method, and propose an iterative algorithm based on a golden section search to optimize the power splitting factor. We also verify its convergence and analyze its complexity. Simulation results demonstrate that the algorithm and scheme proposed in this paper achieve better performance and lower complexity when compared to existing methods.