Low-power wide-area technologies have demonstrated their usefulness in a wide variety of Internet of Things applications. New applications are emerging, requiring a mesh or point-to-point (P2P) topology, in contrast to the conventional star-of-stars topology. In this article, we evaluate the coverage and model the path loss (PL) of these links, based on experimental campaigns in three environments: 1) urban; 2) forest; and 3) coastal. More obstructions, scattering, and diffraction are encountered because the terminals are typically at a low height. This results in a higher PL compared to the star-of-stars topology. Consequently, more packets drop below the receiver sensitivity. Realistic PL parameters are estimated by also taking the censored data into account. The packet error ratio is determined based on the estimated PL parameters to evaluate the performance of P2P links. Even in these adverse environments, 80% of the transmitted packets are successfully received at a distance of approximately 200 m. Moreover, a range of over 4 km is observed in the line-of-sight scenario. Despite the unfavorable radio propagation in the urban scenario and the densely forested terrain, a maximum range of 1 km is achieved.

中文翻译：

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LoRa点对点路径损耗的表征：考虑了删失数据的测量活动和建模

低功耗广域技术已在各种物联网应用中证明了其有用性。与传统的星型拓扑相比，新的应用正在出现，需要网状或点对点（P2P）拓扑。在本文中，我们基于三种环境下的实验性活动，评估了这些链接的覆盖范围并为这些链接的路径损耗（PL）建模：2）森林；3）沿海地区。由于端子通常处于较低的高度，因此会遇到更多的障碍物，散射和衍射。与星型拓扑相比，这会导致更高的PL。因此，更多的数据包下降到接收器灵敏度以下。通过考虑审查数据也可以估算出实际的PL参数。根据估计的PL参数确定数据包错误率，以评估P2P链路的性能。即使在这些不利的环境中，也可以在大约200 m的距离处成功接收80％的已发送数据包。此外，在视线场景中观察到的距离超过4 km。尽管在城市场景和森林茂密的地形中无线电传播不利，但仍可实现最大1 km的射程。