Weighted sum power maximization for STAR-RIS-aided SWIPT systems with nonlinear energy harvesting  

作　　者：Weiping SHI Cunhua PAN Feng SHU Yongpeng WU Jiangzhou WANG Yongqiang BAO Jin TIAN 

机构地区：[1]School of Network and Communication,Nanjing Vocational College of Information Technology,Nanjing 210023,China [2]National Mobile Communications Research Laboratory,Southeast University,Nanjing 211189,China [3]School of Information and Communication Engineering,Hainan University,Hainan 570228,China [4]School of Electronic and Optical Engineering,Nanjing University of Science and Technology,Nanjing 210094,China [5]Shanghai Key Laboratory of Navigation and Location Based Services,Shanghai Jiao Tong University,Shanghai 200240,China [6]School of Engineering,University of Kent,Canterbury CT27NT,UK [7]School of Information and Communication Engineering,Nanjing Institute of Technology,Nanjing 211167,China [8]Engineering School of Networks and Telecommunications,Jinling Institute of Technology,Nanjing 211169,China

出　　处：《Science China(Information Sciences)》2024年第10期339-354,共16页中国科学（信息科学）（英文版）

基　　金：supported in part by National Natural Science Foundation of China(Grant Nos.U22A2002,62071234);Hainan Province Science and Technology Special Fund(Grant No.ZDKJ2021022);Scientific Research Fund Project of Hainan University(Grant No.KYQD(ZR)-21008);Collaborative Innovation Center of Information Technology,Hainan University(Grant No.XTCX2022XXC07);Key Special Project of Technology from Nanjing City Government,China(Grant No.202309010)。

摘　　要：The conventional reconfigurable intelligent surface(RIS)is limited to reflecting incident signals,thereby imposing constraints on the placement of the transmitter and receiver,which hinders achieving comprehensive signal coverage across an entire area.This paper investigates a simultaneously transmitting and reflecting(STAR)-RIS-aided simultaneous wireless information and power transfer(SWIPT)system with a nonlinear energy harvesting model under three different RIS transmission protocols:energy splitting(ES),time switching(TS),and mode switching(MS).The objective of this paper is to maximize the weighted sum power(WSP)of all energy harvesting receivers(EHRs)while ensuring fairness in the collected power among them.This is achieved by jointly optimizing the transmit beamforming at the base station(BS)and the transmission and reflection coefficients at the STAR-RIS,subject to rate constraints for information decoding receivers(IDRs),transmit power constraint at the BS,and coefficient constraints of each element at the STAR-RIS corresponding to the three protocols.Solving this optimization problem poses challenges because of the complicated objective function and numerous coupled optimization variables of the ES STAR-RIS.To address this complexity,an efficient alternating optimization(AO)approach is proposed as an iterative solution method that achieves suboptimal results.The AO algorithm is then extended to MS STAR-RIS and TS STAR-RIS.Specifically,for MS STRA-RIS,binary constraints in the STAR-RIS coefficient optimization subproblem are handled using the first-order approximation technique along with the penalty function method.For TS STAR-RIS,apart from optimizing BS transmit beamforming and STAR-RIS coefficients subproblems,the transmission and reflection time allocation of STAR-RIS also needs optimization.Numerical findings demonstrate that compared to conventional RIS-aided systems,utilizing three different protocols in a STAR-RIS-aided system can enhance power collection at EHRs while expanding the receiver pl

关 键 词：STAR-RIS BEAMFORMING SWIPT alternating optimization nonlinear energy harvesting 

分 类 号：TN929.5[电子电信—通信与信息系统]