Improving the Covertness in the Physical-Layer Authentication  

作　　者：Ning Xie TianXing Hu 

机构地区：[1]College of Electronics and Information Engineering,Shenzhen University,Shenzhen 518060,China [2]Guangdong Key Laboratory of Intelligent Information Processing and Shenzhen Key Laboratory of Media Security(Shenzhen University),Shenzhen 518060,China

出　　处：《China Communications》2021年第3期122-131,共10页中国通信（英文版）

基　　金：partially supported by Natural Science Foundations of China(No.61972262);National Key R&D Project of China(No.2020YFB1805404);Natural Science Foundation of Guangdong,China(No.2016A030313046);Fundamental Research Programs of Shenzhen City(No.JCYJ20180305124648757);China Scholarship Council(No.201908440031).

摘　　要：A well-designed Physical-Layer Authentication(PLA)scheme should consider three properties:covertness,robustness,and security.However,the three properties always cause some dilemmas,e.g.,higher covertness leading to lower robustness.This paper concerns the problem of improving the covertness without sacrificing the robustness.This problem is important because of the following reasons:reducing the errors in recovered source message,improving the security,and ease of constructing a multi-factor authentication system.In this paper,we propose three covert PLA schemes to address the problem.In the first scheme,we improve the covertness by reducing the modification ratio on the source message based on an encoding mechanism.In the second scheme,we improve the covertness by optimizing the superimposing angle,which maximizes the minimum distance between the tagged symbols and the boundary line of the demodulation decision for the source message.In the third scheme,referred to as the hybrid scheme,we further improve the covertness by jointly using the advantages of both the above two schemes.Our experimental results show that when the SNR at a legitimate receiver is 25 dB,as compared with the prior scheme,the first scheme improves the covertness by 17:74%,the second scheme improves the covertness by 28:79%,and the third scheme improves the covertness by 32:09%,while they have similar robustness as Received:Aug.07,2020 Revised:Sep.08,2020 Editor:Nanrun Zhou that of the prior scheme.

关 键 词：physical-layer AUTHENTICATION ENCODING covertness superimposing angle SECURITY 

分 类 号：TN918[电子电信—通信与信息系统]