透射反射双功能RIS辅助的SWIPT系统研究  

Research on SWIPT System Assisted by Simultaneously Transmitting and Reflecting RIS

作　　者：贾瑞霞 岳殿武[1] 陈荥 李琦 JIA Ruixia;YUE Dianwu;CHEN Ying;LI Qi(Information Science and Technology College,Dalian Maritime University,Dalian 116026,China)

机构地区：[1]大连海事大学信息科学技术学院,辽宁大连116026

出　　处：《无线电工程》2024年第7期1660-1667,共8页Radio Engineering

基　　金：国家自然科学基金(61971081)。

摘　　要：研究了一种透射反射双功能可重构智能表面(Simultaneously Transmitting and Reflecting Reconfigurable Intelligent Surface,STAR-RIS)辅助的无线携能通信(Simultaneous Wireless Information and Power Transfer,SWIPT)系统。部署STAR-RIS以辅助从多天线接入点(Access Point,AP)到多个单天线信息解码接收器(Information Decoding Receiver,IDR)和能量收集接收器(Energy Harvesting Receiver,EHR)的信息或功率传输。目标是通过联合优化其发射预编码矩阵及STAR-RIS的反射和透射系数矩阵,在IDR可实现通信速率和EHRs的能量收集量约束下,使AP的发射功率最小化。然而,这个优化问题是非凸的,变量之间有着复杂的耦合。为了解决这一问题,采用交替优化算法解耦耦合的变量,对发射预编码矩阵及STAR-RIS的反射和透射系数矩阵可以分别使用半正定松弛(Semidefinite Relaxation,SDR)算法和基于惩罚的算法进行优化。仿真结果表明,STAR-RIS系统方案可以获得比传统的仅反射或仅透射RIS更好的性能。A Simultaneously Transmitting and Reflecting Reconfigurable Intelligent Surface(STAR-RIS)assisted Simultaneous Wireless Information and Power Transfer(SWIPT)system is studied.Specifically,a STAR-RIS is deployed to assist in the information or power transfer from a multi-antenna Access Point(AP)to multiple single-antenna Information Decoding Receiver(IDR)and Energy Harvesting Receiver(EHR)respectively.The goal is to minimize the transmit power at the AP via jointly optimizing the transmission precoding matrices and the transmission-and reflection-coefficient matrices of the STAR-RIS under the communication rate constraints at IDRs and the energy harvesting constraints at EHRs.However,this optimization problem is non-convex with intricately coupled variables.To solve the problem,an alternating optimization algorithm is employed to decouple the coupled variables.Then,the transmission precoding matrices and the transmission-and reflection-coefficient matrices of the STAR-RIS can be optimized by using a semidefinite relaxation method and penalty-based algorithm respectively.The simulation results show that STAR-RIS system scheme can achieve better performance than conventional reflecting or transmitting-only RIS.

关 键 词：透射反射双功能 可重构智能表面 无线携能通信 交替优化 

分 类 号：TN925.2[电子电信—通信与信息系统]