基于通用软件无线电外设的OFDM信道物理密钥量化分析  

Quantitative analysis of physical secret key in OFDM channel based on universal software radio peripheral

作　　者：丁宁 管新荣 杨炜伟 DING Ning;GUAN Xinrong;YANG Weiwei(College of Communications Engineering,Army Engineering University of PLA,Najying Jiangsu 210007,China)

机构地区：[1]中国人民解放军陆军工程大学通信工程学院

出　　处：《计算机应用》2019年第6期1780-1785,共6页journal of Computer Applications

基　　金：国家自然科学基金项目资助项目(61471393,61501512);江苏省青年基金资助项目(BK20150718)~~

摘　　要：为了对比分析实测数据下单门限量化算法与双门限量化算法的性能差异,并通过优化量化参数改善物理密钥性能,采用通用软件无线电外设(USRP)搭建了正交频分复用(OFDM)系统,通过信道估计提取信道幅度特征作为密钥源(实测数据),从密钥一致性、密钥随机性和密钥剩余长度三个方面分析了两种量化算法的性能。基于实测数据得到了单门限量化和双门限量化下密钥一致性、密钥随机性和密钥剩余长度仿真结果。仿真结果表明:在单门限量化算法中,在给定密钥随机性约束下存在最优量化门限使得密钥不一致率最低;在双门限量化算法中,存在最优量化因子使得有效密钥长度最大化;结合Cascade密钥协商算法进行协商时,不同量化算法的密钥一致性与密钥生成速率存在折中关系。In order to compare and analyze the performance of single threshold quantization algorithm and double thresholds quantization algorithm on measured data and improve the performance of physical secret key by optimizing the quantization parameters, an Orthogonal Frequency Division Multiplexing(OFDM) system was built by Universal Software Radio Peripheral(USRP). The channel amplitude feature was extracted as the key source through channel estimation and the performance of the two quantization algorithms was analyzed in terms of consistency, randomness and residual length of secret key. The simulation results of consistency, randomness and residual length of secret key under single threshold quantization and double thresholds quantization were obtained based on measured data. The results show that single threshold quantization algorithm has the optimal quantization threshold to minimize the key inconsistency rate under the given key randomness constraint, double thresholds quantization algorithm has the optimal quantization factor to maximize the effective secret key length, and when Cascade key negotiation algorithm is used for negotiation, there is a trade-off relation between secret key consistency and secret key generation rate in different quantization algorithms.

关 键 词：物理层密钥 量化 通用软件无线电外设 正交频分复用系统 

分 类 号：TP393.09[自动化与计算机技术—计算机应用技术]