基于智能反射表面的中继协作安全通信技术  

A Relay Cooperative Secure Communication Technology Based on Intelligent Reflecting Surface

作　　者：李蒙 任清华[1,2] 张广大 樊志凯 崔祥巍 LI Meng;REN Qinghua;ZHANG Guangda;FAN Zhikai;CUI Xiangwei(Information and Navigation School,Air Force Engineering University,Xi’an 710077,China;Key Laboratory of Aerospace Information Applications,China Electronics Technology Group,Shijiazhuang 050081,China)

机构地区：[1]空军工程大学信息与导航学院,西安710077 [2]中国电子科技集团公司航天信息应用技术重点实验室,石家庄050081

出　　处：《空军工程大学学报（自然科学版）》2022年第3期34-40,52,共8页Journal of Air Force Engineering University(Natural Science Edition)

摘　　要：在传统中继协作的通信过程中,中继节点在对信号处理时,会放大中继节点自身的干扰信号。此外,现实通信场景中往往存在窃听节点窃取重要信息。智能反射表面具备无源反射特性,能对信号的相位进行调整,以及在处理信号时能减少干扰信号的产生。针对中继节点增大干扰信号和安全传输问题,提出了基于智能反射表面的中继协作安全传输技术。考虑通信场景中存在恶意窃听节点,且窃听链路与合法链路的相关性较高的情况下,通过部署智能反射表面将基站发送的信号反射给合法用户,提高系统的安全通信质量。为了解决保密速率表达式的非凸性,采用交替优化、黎曼共轭梯度下降的算法对波束形成向量及反射相位进行交替优化。最后,通过仿真结果验证在3 GHz高频段载波下,基于智能反射表面协作通信技术在数据传输、能效、安全方面的作用优于传统中继协作通信方法。In the communication process of traditional cooperative relay,the relay node itself amplifies the interference signal of the relay node while processing the signal.In addition,eavesdropping nodes often exist in real communication scenarios to steal important information.Intelligent reflecting surface(IRS)is characterized by passive reflection,enabling to adjust the phase of the signal,and reducing the generation of interference signal during signal processing.In view of increasing interference signal and secure transmission of relay nodes,a cooperative secure transmission technology based on IRS is proposed.In consideration of malicious eavesdropping nodes existence in communication scenarios under condition of high correlation between eavesdropping links and legitimate links,the IRS enables to reflect the signals sent by base stations to legitimate users,improving the quality of secure communication of the system.In order to solve the non-convexity of the secret rate expression,alternate optimization and Riemannian conjugate gradient descent algorithms are used to alternate optimization of beamforming vector and reflection phase.Finally,the simulation results verify that under the 3 GHz high frequency carrier,based on the IRS cooperative communication technology is superior to the traditional relay cooperative communication method in terms of data transmission,energy efficiency and security.

关 键 词：智能反射表面 中继协作 交替优化 物理层安全 

分 类 号：TN918[电子电信—通信与信息系统]