有源RIS-MISO系统人工噪声辅助物理层安全  

Artificial Noise Assisted Physical Layer Security in Active RIS-MISO System

作　　者：田壮赫 姜斌[1] 邱雨[1] 赵宜楠 包建荣[1] TIAN Zhuanghe;JIANG Bin;QIU Yu;ZHAO Yinan;BAO Jianrong(Hangzhou Dianzi University,Hangzhou Zhejiang 310018,China)

机构地区：[1]杭州电子科技大学,浙江杭州310018

出　　处：《通信技术》2024年第10期1066-1071,共6页Communications Technology

基　　金：国家自然科学基金(U1809201);浙江省自然科学基金(LZ24F010005)。

摘　　要：针对可重构智能表面(Reconfigurable Intelligent Surface,RIS)-多输入单输出系统安全传输中反射信道链路“双衰落”效应限制系统提高保密性的问题,提出了一种有源RIS与人工噪声结合的物理层安全方案。它以系统保密率最大化为目标,构建一个优化波束成形矩阵、人工噪声协方差矩阵和有源RIS反射系数矩阵的系统模型,并用交替优化解决非凸问题。此外,在联合优化波束成形矩阵与人工噪声协方差矩阵时,使用了一阶泰勒展开和半定松弛方法简化问题,然后通过内点法进行求解;在优化有源RIS反射系数矩阵时,联合半定松弛与最小化-最大化算法简化问题,同样采用内点法进行求解。仿真表明,有源RIS能有效克服“双衰落”效应影响,且引入的人工噪声能破坏窃听端信道,联合方案相较于现有方案有更高的保密性能。To address the issue of“double fading”effect of reflective channel links in the secure transmissions of RIS(Reconfigurable Intelligent Surface)-MISO(Multiple-Input Single-Output)systems,which limits the system to improve the confidentiality,this paper proposes a physical layer security scheme that combines ARIS(Active RIS)with artificial noise.It aims to maximize the systematical confidentiality rate by constructing a system model that optimizes the beamforming matrix,the artificial noise covariance matrix,and the ARIS reflection coefficient matrix,and solves the non-convex problem using alternating optimization.Moreover,in the joint optimization of the beamforming matrix and the artificial noise covariance matrix,the paper uses a first-order Taylor expansion and a SDR(Semi-Definite Relaxation)method to simplify the problem,which is then solved by IPM(Interior Point Method).When optimizing the ARIS reflection coefficient matrix,the problem is simplified by jointly employing SDR and MM(Minimization-Maximization)algorithm,with the IPM being utilized for the solution.Simulation results demonstrate that the ARIS can effectively overcome the“double fading”effect,and the introduced artificial noise can disrupt the eavesdropper’s channel,thus the joint scheme has higher confidentiality performance compared with existing schemes.

关 键 词：物理层安全 有源可重构智能表面 波束成形设计 人工噪声 

分 类 号：TN918.91[电子电信—通信与信息系统]