Abstract:

This paper studies the outage probability and intercept probability of the primary user and the cognitive user in the cognitive relay network, and puts forward a scheme to Change the Transmission Mode according to the Eavesdropping Behavior（CTMEB）, the primary user and the cognitive user adopt different signal transmission methods according to whether or not the user is eavesdropping. If E only eavesdropping CS, the primary user uses direct transmission to transmit the signal, if E eavesdropping CS and PS, the primary user selects the link transmission signal with high SNR according to the channel state. The outage probability and intercept probability of the primary user and the cognitive user are analyzed. Finally, MATLAB is used to verify the effectiveness of the CTMEB scheme in improving the outage probability and intercept probability of the primary user and the cognitive user.

Key words: cognitive relay network, physical layer security, outage probability, intercept probability, multi-eavesdropper

摘要：

对认知中继网络中主用户和认知用户的中断概率和窃听概率进行了研究，提出了一种根据窃听行为改变传输方式（CTMEB）的方案，即主用户和认知用户会根据是否被窃听用户窃听而采用不同的信号传输方式。若E只窃听CS，主用户采用直接传输的方式传递信号；若E窃听CS和PS，主用户根据信道状态选择信噪比较高的路线传输信号。分析推导出了窃听CS与窃听CS和PS时主用户和认知用户的中断概率和窃听概率。通过MATLAB验证了采用CTMEB方案对提高主用户和认知用户的窃听概率和中断概率的有效性。

关键词: 认知中继网络, 物理层安全, 中断概率, 窃听概率, 多窃听用户