FTN传输条件下极化码帧间物理层安全结构设计  

Inter-block physical layer security structure design for polar code under FTN transmission

作　　者：张晨宇[1] 刘荣科[1] ZHANG Chenyu;LIU Rongke(School of Electronic and Information Engineering,Beijing University of Aeronautics and Astronautics,Beijing 100083,China)

机构地区：[1]北京航空航天大学电子信息工程学院,北京100083

出　　处：《北京航空航天大学学报》2018年第10期2217-2223,共7页Journal of Beijing University of Aeronautics and Astronautics

基　　金：国家自然科学基金(91438116)~~

摘　　要：极化码是适用于物理层wiretap信道安全模型的一种编码方式,针对在超奈奎斯特(FTN)条件下传输的极化码,设计了一种无需获知窃听信道信噪比(SNR)的帧间链式加密的安全结构。通过混淆结构将对合法接收端可靠而对非法窃听端阻塞的码元进行扩散,利用物理层主信道和窃听信道的差异,在每一帧中生成主信道可译而窃听信道不可译的密钥序列,对下一帧进行加密,实现安全容量的帧间传输。仿真结果显示,在FTN加速场景和窃听信道SNR相对于主信道波动的前提下,提出的极化码帧间安全结构可在wiretap信道的平均信道退化程度为0 d B时实现信息的安全传输。Wiretap channel is a widely-used model to describe physical layer security and polar code shows potential in wiretap channel model due to its polarization characteristic. A new inter-block encryption security scheme without the need of acquiring signal-to-noise ratio（ SNR） is designed for the polar code under faster-than-Nyquist（ FTN） transmission condition. With the scrambling module and the channel degradation of the wiretap model,the bits noiseless for the legal receiver but noisy for the eavesdropper are diffused and a one-time-pad secret key can be generated in each block. The physical layer difference of the main channel and the wiretap channel is applied to generate secret key sequence with is decipherable for the legal receiver and undecipherable for the eavesdropper. The secret key sequence is applied for encrypting the next block,achieving inter-block security transmission within secrecy capacity. The simulation result shows that under the circumstance of FTN signaling,when the channel SNR of eavesdropper is fluctuating from that of the main channel,the inter-block secrecy scheme proposed for the polar code can achieve confidential information transmission even when the average channel degradation of the wiretap channel is 0 d B.

关 键 词：极化码 wiretap信道 超奈奎斯特(FTN) 物理层 帧间安全结构 

分 类 号：TN918[电子电信—通信与信息系统]