In view of the scarcity of spectrum resources in wireless communication, it is studied in this paper over the two-hop cognitive secrecy transmission scheme of decoding and forwarding (DF) unmanned aerial vehicles (UAVs) assisted relay with energy harvesting under Nakagami- ${m}$ channel. It is worth noting that the terminal node is equipped with multiple antennas and the optimal antenna selection can be adopted for signal reception. Meanwhile, the UAV assisted relay uses time switching (TS) and power splitting (PS) energy harvesting techniques and adopts optimal secrecy capacity selection scheme. It is successfully derived for the exact closed form expressions of non-zero secrecy capacity probability and optimal secrecy outage probability while the eavesdropper has no channel state information (CSI). Moreover, the system asymptotic secrecy outage probability demonstrates the secrecy diversity order and secrecy diversity gains of the UAV assisted relay cognitive network under Nakagami- ${m}$ channel. Furthermore, joint optimization of power splitting factor and other parameters can effectively increase the system secrecy capacity and improve the system secrecy performance. Simulation results verify the correctness of the theoretical derivation and the effectiveness of the proposed scheme, which demonstrate that the proposed algorithm outperforms the other compared schemes.

中文翻译：

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Nakagami-m信道下认知网络无人机辅助中继和天线选择的保密中断分析

针对无线通信中频谱资源的稀缺性，本文研究了解码转发（DF）无人机（UAV）辅助中继能量收集的Nakagami-${ m}$ 频道。值得注意的是，终端节点配备多根天线，可以采用最优天线选择进行信号接收。同时，无人机辅助中继采用时间切换（TS）和功率分配（PS）能量收集技术，采用最优保密容量选择方案。成功推导出窃听者没有信道状态信息(CSI)时非零保密容量概率和最优保密中断概率的精确闭式表达式。而且，系统渐近保密中断概率证明了无人机辅助中继认知网络在Nakagami-${m}$信道下的保密分集阶和保密分集增益。此外，功率分流因子等参数的联合优化可以有效提高系统保密能力，提高系统保密性能。仿真结果验证了理论推导的正确性和所提出方案的有效性，表明所提出的算法优于其他比较方案。功率分流因子等参数联合优化，可以有效提高系统保密能力，提高系统保密性能。仿真结果验证了理论推导的正确性和所提出方案的有效性，表明所提出的算法优于其他比较方案。功率分流因子等参数联合优化，可以有效提高系统保密能力，提高系统保密性能。仿真结果验证了理论推导的正确性和所提出方案的有效性，表明所提出的算法优于其他比较方案。