We present a general and tractable fading model for line-of-sight (LOS) scenarios, which is based on the product of two independent and non-identically distributed $\kappa $ - $\mu $ shadowed power envelopes. Simple closed-form expressions for the probability density function, cumulative distribution function and moment-generating function are derived, which are as tractable as the corresponding expressions derived from a product of Nakagami- $m$ random variables. This model simplifies the challenging characterization of LOS product channels, as well as combinations of LOS channels with non-LOS ones. We leverage these results to analyze performance measures of interest in the contexts of wireless powered and backscatter communications, where both forward and reverse links are inherently of LOS nature, as well as in device-to-device communications subject to composite fading. In these contexts, the proposed model shows a higher flexibility when fitting field measurements with respect to conventional approaches based on product distributions with deterministic LOS, together with a more complete physical interpretation of the underlying propagation characteristics.

中文翻译：

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适用于视线场景的可操作产品渠道模型

我们提出了一种适用于视线 (LOS) 场景的通用且易于处理的衰落模型，该模型基于两个独立且非相同分布的乘积 $\kappa $ —— $\亩 $ 阴影功率包络。导出概率密度函数、累积分布函数和矩生成函数的简单闭式表达式，它们与从 Nakagami 的乘积导出的相应表达式一样易于处理 百万美元 随机变量。该模型简化了 LOS 产品通道的挑战性表征，以及 LOS 通道与非 LOS 通道的组合。我们利用这些结果来分析在无线供电和反向散射通信环境中感兴趣的性能度量，其中前向和反向链路本质上都是 LOS 性质，以及在受复合衰落影响的设备到设备通信中。在这些情况下，相对于基于具有确定性 LOS 的产品分布的传统方法以及对潜在传播特性的更完整的物理解释，所提出的模型在拟合现场测量时显示出更高的灵活性。