中文摘要：

在认知中继安全通信网络中,研究了自适应解码转发中继节点采用机会式传输策略的物理层安全性能。在满足主用户对干扰功率限制的条件下,推导了在瑞利信道下的安全中断概率的闭合表达式,并进一步推导了安全中断概率性能的渐近表达式,从而可以直观地对系统性能进行分析。仿真结果验证了理论分析的正确性,并揭示了在认知中继网络中各系统参数对机会式传输方案的安全性能的影响。结果表明,可以通过增大主用户的最大干扰功率容限和增加次级中继节点个数来提升系统安全性能。

英文摘要：

The physical layer security performance of opportunistic transmission strategy applied at adaptive decode-and-forward relay nodes is investigated in the cognitive relay secure communication networks.The closed-form expression of secrecy outage probability is derived over Rayleigh fading channels,under the interference power constraint of the primary user,and the asymptotic expression of secrecy outage probability is further provided to explicitly analyze the system performance.The simulation results verify the correctness of theoretical analysis and identify the effects of several system parameters on the secrecy performance of the opportunistic transmission strategy in the cognitive relay networks.It suggested that the system secrecy performance could be greatly improved by increasing the peak interference power constraint of primary user or the number of secondary relay nodes.