Power Allocation and Beamforming Vectors Optimization in STAR-RIS Assisted SWIPT
Pengfei Zhao, Jiakuo Zuo, Chenchi Wen
Abstract
This paper proposes a network of simultaneously transmitting and reflecting reconfigurable intelligent surface (STAR-RIS) assisted simultaneous wireless information and power transfer (SWIPT) system, where time switching (TS) protocol is applied. The objective is to maximize the sum rate of all information decoding receivers (IDRs) via jointly optimizing the power allocation of IDRs, beamforming vectors at the STAR-RIS while taking into account the power of the IDRs and the received energy of energy harvesting receivers (EHRs). To solve the formulated non-convex problem, we first convert the problem into a standard semidefinite programming (SDP) problem, and then solve it by applying Gaussian Randomization algorithm and successive convex approximation (SCA) algorithm. Simulation results prove that the two algorithms can improve the performance of STAR-RIS.