IRS辅助的通感一体化系统的安全通信  

Secure Transmission for IRS Aided Integrated Sensing and Communication System

作　　者：傅友华[1,2] 卞晓晨 FU Youhua;BIAN Xiaochen(College of Electronic and Optical Engineering and College of Flexible Electronics(Future Technology),Nanjing University of Posts and Telecommunications,Nanjing,Jiangsu 210023,China;National and Local Joint Engineering Laboratory of RF Integration and Micro-Assembly Technology,Nanjing University of Posts and Telecommunications,Nanjing,Jiangsu 210023,China)

机构地区：[1]南京邮电大学电子与光学工程学院、柔性电子(未来技术)学院,江苏南京210023 [2]南京邮电大学射频集成与微组装技术国家地方联合工程实验室,江苏南京210023

出　　处：《信号处理》2023年第7期1194-1202,共9页Journal of Signal Processing

基　　金：射频集成与微组装技术国家地方联合工程实验室开放课题(KFJJ20210101);装备预研重点实验室基金(JKW202209)。

摘　　要：本文研究了智能反射面(Intelligent Reflecting Surface, IRS)辅助通感一体化(Integrated Sensing and Communication, ISAC)系统的安全通信。其中基站希望在IRS的帮助下,在窃听用户存在的情况下向合法用户发送消息并同时检测可信目标。本文的目的是联合设计基站的发射波束形成向量和IRS的反射波束形成向量,以最大化保密速率,同时满足检测目标所需信噪比(Signal-to-Noise Ratio, SNR)阈值、发射功率约束和IRS反射系数的单位模约束。为了解决这个复杂的非凸问题,本文提出了一种基于半正定松弛(Semidefinite Relaxation, SDR)和交替优化的有效算法来解决该问题。仿真结果表明,该系统既可以提供有效的目标检测,保证预定义的SNR阈值,也可以提供安全的通信。同时证实了与没有IRS的方案相比,IRS辅助实现了更高的保密速率,也表明了在ISAC系统中部署IRS的优势和所提出算法的有效性。This paper investigated the secure communication for Integrated Sensing and Communication(ISAC)system as⁃sisted by Intelligent Reflecting Surface(IRS).With the aid of the IRS,the base station desired to deliver messages to a le⁃gitimate user and detect a trusted target in the presence of an eavesdropping user.We aimed to jointly design the transmit beamforming vector of the base station and the reflection beamforming vector of IRS to maximize the secrecy rate,while sat⁃isfying the required signal-to-noise ratio(SNR)threshold for the sensing target,transmit power constraint and the unitmodulus constraint of the IRS reflection coefficient.However,the problem was non-convex due to the non-convex of the se⁃crecy rate function.To tackle this issue,we proposed an effective algorithm based on the semidefinite relaxation(SDR)and an alternation optimization approach to solve this problem.The simulation results show that the system can not only provide effective target detection and ensure predefined SNR threshold,but also provide secure communication.At the same time,it proves that IRS can help to achieve higher secrecy rate compared with the scheme without IRS,which shows the advantages of deploying IRS in the Integrated Sensing and Communication system and the effectiveness of the proposed algorithm.

关 键 词：通感一体化 智能反射面 安全通信 半正定松弛 

分 类 号：TN929.5[电子电信—通信与信息系统]