The use of unmanned aerial vehicle (UAV) as aerial relay, i.e. UAV-assisted relaying, has the advantages of easy deployment, agility, and mobility compared to traditional ground relaying. In this paper, our goal is to acquire the universal outage probability (OP) analytical expression for multi-rotor UAV-assisted AF relaying with transceiver hardware impairments (HIs) while considering a practical large-scale fading. Contrary to the existing works on the UAV-assisted relaying, where the OP was derived by assuming a specific small-scale fading, we make a more general assumption of arbitrary small-scale fading and thereafter apply an integral region shape-based approximate method (IRS-AM) to deduce a closed-form OP expression with adjustable error in a more common way. The derivation process is free of the concrete model of the small-scale fading while the finial OP expression has a concise and intuitive form, which is determined by the cumulative distribution function (CDF) of the small-scale fading in both two links. Based on the derived results, we demonstrate the ceiling effect caused by HIs on the multi-rotor UAV-assisted AF relaying and obtain the end-to-end signal-to-noise-and-distortion ratio (SNDR) bound, which depends on the aggregate HIs levels and determines whether the considered relay network is always in outage or not. Computer simulations validate our studies and reveal the influence of HIs on the OP and the optimal UAV altitude.

与传统的地面中继相比，使用无人机（UAV）作为空中中继，即无人机辅助中继，具有易于部署，敏捷和移动的优势。在本文中，我们的目标是在考虑实际的大规模衰落的同时，获取具有收发器硬件损伤（HI）的多旋翼无人机辅助AF中继的通用中断概率（OP）解析表达式。与无人机辅助中继的现有工作相反，在现有的工作中，OP是通过假设特定的小规模衰落而推导的，我们对任意小规模衰落进行了更一般的假设，然后应用基于积分区域形状的近似方法（ （IRS-AM）以更常见的方式推导具有可调误差的闭式OP表达式。推导过程没有小规模衰落的具体模型，而最终的OP表达式具有简洁直观的形式，这取决于两条链路中小规模衰落的累积分布函数（CDF）。基于得出的结果，我们证明了HI对多旋翼无人机辅助AF中继的天花板效应，并获得了端对端信噪比（SNDR）的范围，该范围取决于汇总HI级别，并确定所考虑的中继网络是否始终处于中断状态。计算机仿真验证了我们的研究结果，并揭示了HI对OP和最佳无人机高度的影响。它由两条链路中小规模衰落的累积分布函数（CDF）决定。基于得出的结果，我们证明了HI对多旋翼无人机辅助AF中继的天花板效应，并获得了端对端信噪比（SNDR）的范围，该范围取决于汇总HI级别，并确定所考虑的中继网络是否始终处于中断状态。计算机仿真验证了我们的研究结果，并揭示了HI对OP和最佳无人机高度的影响。它由两条链路中小规模衰落的累积分布函数（CDF）决定。基于得出的结果，我们证明了HI对多旋翼无人机辅助AF中继的天花板效应，并获得了端对端信噪比（SNDR）的范围，该范围取决于汇总HI级别，并确定所考虑的中继网络是否始终处于中断状态。计算机仿真验证了我们的研究结果，并揭示了HI对OP和最佳无人机高度的影响。取决于总HIs级别，并确定所考虑的中继网络是否始终处于中断状态。计算机仿真验证了我们的研究结果，并揭示了HI对OP和最佳无人机高度的影响。取决于总HIs级别，并确定所考虑的中继网络是否始终处于中断状态。计算机仿真验证了我们的研究结果，并揭示了HI对OP和最佳无人机高度的影响。