基于不存在直接链路的具有不可信中继的三节点系统,本文在协作干扰模型中引入功率分配因子,对两种放大转发因子下系统的中断概率和遍历保密容量进行了计算及对比分析。首先,系统采用平均放大因子,推导出其保密中断概率;然后,在引入同样功率分配因子的基础上,系统改用自适应瞬时放大因子,得出保密中断概率的下界;为了对比,本文接着给出了系统两种情况下的遍历保密容量;最后,仿真验证了中断概率和遍历保密容量计算的准确性,数值仿真表明引入功率分配因子可减小系统的中断概率和提高系统的遍历保密容量,瞬时放大因子下系统性能较平均放大因子下更好。
In the practical communication systems,relay can't be completely trusted,so the research on untrusted relay is very necessary. Based on the three-node untrusted relay networks without the direct link,this papper aimed to introduce the power allocation factor in the cooperative interference model,and calculate and analyze the outage probability and ergodic secrecy capacity of the system on two kinds of amplifying coefficients. We first derived the secrecy outage probability on the average amplifying coefficient. Subsequently,on the basis of the same power allocation factor,the adaptive instantaneous amplifying coefficient was used and the lower bound of the secrecy outage probability was derived. For comparison purposes,we gave the ergodic secrecy capacity of the system. Finally,the simulation results confirmed that the derived outage probability and ergodic secrecy capacity was exact,numerical simulations show that the introduction of power allocation factor can reduce the outage probability and improve the ergodic secrecy capacity of the system,the performance of the system on the instantaneous amplifying coefficient is better than the average amplifying coefficient.