全双工模式下利用干扰抑制技术实现物理层密钥生成  

Physical layer key generation based on jamming suppression technology in full duplex mode

作　　者：徐鹏[1,2] 凌桐 杨俊 XU Peng;LING Tong;YANG Jun(School of Communications and Information Engineering,Chongqing University of Posts and Telecommunications,Chongqing 400065,P.R.China;Chongqing Key Laboratory of Mobile Communications Technology,Chongqing,400065,P.R.China)

机构地区：[1]重庆邮电大学通信与信息工程学院,重庆400065 [2]移动通信技术重庆市重点实验室,重庆400065

出　　处：《重庆邮电大学学报（自然科学版）》2024年第6期1150-1158,共9页Journal of Chongqing University of Posts and Telecommunications(Natural Science Edition)

基　　金：重庆市自然科学基金创新发展联合基金项目(CSTB2023NSCQ-LZX0066);重庆市自然科学基金面上项目(CSTB2022NSCQ-MSX1132,CSTB2022NSCQ-MSX0990)。

摘　　要：窃听者距离合法用户非常近时,合法信道和窃听信道的相关性极强,导致系统的可达密钥速率过低。针对这一问题,提出了一种基于全双工(full duplex,FD)干扰抑制的物理层密钥生成方法。通过各节点进行信道估计,同时合法用户发送干扰来抑制窃听者窃取信息,进而合法用户通过在无噪的公共信道上进行密钥协商来获得密钥;利用遍历性的特征和Jensen不等式推导出了系统密钥容量下界的解析表达式。仿真结果表明,少量的干扰信号功率能够提升系统的可达密钥速率;与传统的半双工(half duplex,HD)无干扰系统相比,有干扰的全双工系统有着显著的性能提升。To address the issue of extremely low achievable key rates caused by a strong correlation between the legitimate channel and the eavesdropping channel when an eavesdropper is very close to legitimate users,we propose a physical layer key generation method based on full-duplex(FD)interference suppression.Nodes perform channel estimation while legitimate users transmit interference to suppress eavesdroppers from stealing information.Subsequently,legitimate users conduct key agreement over a noiseless public channel to derive the key.Using the ergodicity property and Jensen’s inequality,an analytical expression for the lower bound of the system’s key capacity is derived.Simulation results show that a small amount of interference signal power can improve the system’s achievable key rate significantly.Moreover,it is demonstrated that the full-duplex system with interference offers substantial performance improvements compared to the traditional half-duplex(HD)system without interference.

关 键 词：全双工 物理层安全 密钥生成 干扰 

分 类 号：TN918[电子电信—通信与信息系统]