利用信道衰落幅度差异隐藏私密信息的物理层安全编码方法  

The Physical Layer Secrecy Coding Method of Hiding Confidential Information using Amplitude Difference of Fading Channel

作　　者：白慧卿[1] 金梁[1] 钟州[1] 黄开枝[1] 

机构地区：[1]国家数字交换系统工程技术研究中心,河南郑州450002

出　　处：《信号处理》2015年第1期17-25,共9页Journal of Signal Processing

基　　金：国家自然科学基金资助课题(61171108)

摘　　要：针对现有物理层安全编码方法对信道差异利用不充分导致安全间隙较大的问题,本文首先建立了衰落信道下的物理层安全传输模型;然后通过分析不同衰落幅度下私密信息的译码错误概率,给出了与信道衰落幅度特征相匹配的私密信息隐藏位置选取规则;最后结合私密信息置乱将译码残余比特错误扩散到整个码字中,进一步提高窃听者对私密信息的译码错误概率。仿真结果表明,该方法的安全间隙比直接传输和仅私密信息置乱的方法分别缩小了23.5d B和4.5d B。This paper focused on the problem that the existing physical layer secrecy coding has a large security gap caused by the insufficient using of channel characteristic difference.Firstly,this study established a physical layer secrecy transmission model in fading channel.Then through the analysis of the bit error probability of confidential information under different channel fading amplitude,a channel fading amplitude matched confidential information hiding place selection rule is given.Finally the scrambling was used to spread the error to the whole code words,which increased Eve’s error probabil-ity.The simulation results show that the security gap of this method is reduced by 23.5dB and 4.5dB compared with direct transfer and scrambling,respectively.

关 键 词：物理层安全编码 信道差异 衰落幅度 低密度奇偶校验码 安全间隙 私密信息置乱 

分 类 号：TN918[电子电信—通信与信息系统]