Sum-Rate Maximization in Active RIS-Assisted Multi-Antenna WPCN  

作　　者：Jiang Jie Lyu Bin Chen Pengcheng Yang Zhen 

机构地区：[1]School of Communications and Information Engineering,Nanjing University of Posts and Telecommunications,Nanjing 210003,China [2]Jiangsu Provincial Key Laboratory of Photonic and Electronic Materials Sciences and Technology,Nanjing University,Nanjing 210003,China

出　　处：《China Communications》2024年第6期23-39,共17页中国通信（英文版）

基　　金：supported in part by the National Natural Science Foundation of China (No.62071242 and No.61901229);in part by the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX22 0967);in part by the Open Research Project of Jiangsu Provincial Key Laboratory of Photonic and Electronic Materials Sciences and Technology (No.NJUZDS2022-008)

摘　　要：In this paper,we propose an active reconfigurable intelligent surface(RIS)enabled hybrid relaying scheme for a multi-antenna wireless powered communication network(WPCN),where the active RIS is employed to assist both wireless energy transfer(WET)from the power station(PS)to energyconstrained users and wireless information transmission(WIT)from users to the receiving station(RS).For further performance enhancement,we propose to employ both transmit beamforming at the PS and receive beamforming at the RS.We formulate a sumrate maximization problem by jointly optimizing the RIS phase shifts and amplitude reflection coefficients for both the WET and the WIT,transmit and receive beamforming vectors,and network resource allocation.To solve this non-convex problem,we propose an efficient alternating optimization algorithm with the linear minimum mean squared error criterion,semidefinite relaxation(SDR)and successive convex approximation techniques.Specifically,the tightness of applying the SDR is proved.Simulation results demonstrate that our proposed scheme with 10 reflecting elements(REs)and 4 antennas can achieve 17.78%and 415.48%performance gains compared to the single-antenna scheme with 10 REs and passive RIS scheme with 100 REs,respectively.

关 键 词：active reconfigurable intelligent surface BEAMFORMING sum-rate maximization wireless powered communication network 

分 类 号：TN929.5[电子电信—通信与信息系统]