无线平坦衰落信道的密钥生成速率研究

Research of secret key rate in the wireless flat fading channel

针对传统窃听信道模型中假定合法信道完全互易、窃听方只处理合法双方一方信号的问题,对传统的窃听信道模型进行了改进。一方面引入相关系数ρ0来刻画合法信道的互易程度,另一方面考虑窃听方能够获取并利用合法双方的信息。在此基础上,推导得到了密钥生成速率的解析表达式,并对影响密钥生成速率的因素进行了仿真分析。仿真结果表明,密钥生成速率随合法信道的相关系数ρ0、信噪比γ的增大而增大,随合法信道与窃听信道之间的相关系数ρ1、ρ2的增大而减小。

In traditional wiretapping channel models,the legitimate channels are assumed to be completely reciprocal.Besides,the wiretapper can only receive the signals from one side of the legitimate users,which are not in accord with the process of secret key generation.In this paper,the traditional models are improved,on the one hand,the correlation coefficient is introduced to characterize the reciprocal degree of the legitimate channels,on the other hand,the wiretapper is assumed to acquire the information from both the legitimate users.Moreover,the expression of the secret key rate is deduced,the factors affecting the rate are also simulated and analyzed.The results show that the rate is increased with the correlation coefficient of the legitimate channels and SNR,but the rate is decreased when the correlation coefficients of the wiretapper increase.