STAR-RIS辅助URLLC-NOMA系统的联合波束成形设计  

Joint Beamforming Design for STAR-RIS Assisted URLLC-NOMA System

作　　者：朱建月 吴雨桐 陈晓[3] 谢亚琴[1] 许尧 张治中 ZHU Jianyue;WU Yutong;CHEN Xiao;XIE Yaqin;XU Yao;ZHANG Zhizhong(School of Electronic and Information Engineering,Nanjing University of Information Science and Technology,Nanjing 210044,China;School of Cyberspace Security,Southeast University,Nanjing 211189,China;School of Artificial Intelligence/School of Future Technology,Nanjing University of Information Science,Nanjing University of Information Science and Technology,Nanjing 210044,China)

机构地区：[1]南京信息工程大学电子与信息工程学院,南京210044 [2]东南大学网络空间安全学院,南京211189 [3]南京信息工程大学人工智能学院(未来技术学院),南京210044

出　　处：《电子与信息学报》2025年第2期409-417,共9页Journal of Electronics & Information Technology

基　　金：国家自然科学基金(62101273);江苏省自然科学基金(BK20220439,BK20220438);江苏省高等学校基础科学(自然科学)研究面上项目(22KJB510005,22KJB510033);江苏省重点研发计划(BE2023088);江苏省双创团队((2023)200008号)。

摘　　要：针对超可靠低时延通信(URLLC)场景,该文研究了融合透射与反射功能的智能超表面(STAR-RIS)辅助的非正交多址接入(NOMA)系统的传输设计。具体而言,该文联合设计了基站端的波束成形向量、RIS端的透射相移矩阵和反射相移矩阵,以在满足基站总功率约束的条件下实现能耗最小化。为解决所提出的非凸问题,该文首先分析了有限块长传输下的用户速率函数特性,并据此将优化问题进行等价转换。随后,采用交替优化和半正定松弛(SDR)方法来解决联合波束设计问题。实验结果表明,与正交多址接入和传统RIS方案相比,所提出的方法在能耗性能上有显著提升。Objective This paper addresses the energy efficiency challenge in Ultra-Reliable Low-Latency Communication(URLLC)systems,crucial for mission-critical applications such as industrial automation and remote surgery.The integration of Simultaneously Transmitting and Reflecting Reconfigurable Intelligent Surfaces(STAR-RIS)with Non-Orthogonal Multiple Access(NOMA)is proposed to improve spectral efficiency and coverage while meeting URLLC’s stringent reliability and latency requirements.However,the joint optimization of base station beamforming,STAR-RIS transmission,and reflection matrices presents a non-trivial problem due to non-convexity and coupled variables.This work aims to minimize energy consumption under a total power constraint by jointly designing these parameters,advancing STAR-RIS-aided NOMA systems for URLLC.Methods To address the non-convex optimization problem,the proposed methodology involves several key steps.First,the user rate function under finite blocklength transmission is analyzed,considering the specific requirements of URLLC.This analysis facilitates the reformulation of the original problem into an equivalent form more amenable to optimization.Specifically,the rate function is approximated using a Taylor series expansion,and the effect of finite blocklength on decoding error probability is incorporated into the optimization framework.Next,an alternating optimization framework is adopted to decouple the joint design problem into subproblems,each focused on optimizing either the base station beamforming,the STAR-RIS transmission matrix,or the reflection matrix.Semidefinite Relaxation(SDR)techniques are then applied to address the non-convexity of these subproblems,ensuring efficient and tractable solutions.The SDR method transforms the original non-convex constraints into convex ones by relaxing certain matrix rank constraints,which are subsequently recovered using randomization techniques.The proposed approach is validated through extensive simulations,comparing its performance with Orthogona

关 键 词：智能反射面 非正交多址接入技术 波束成形设计 

分 类 号：TN929.5[电子电信—通信与信息系统]