In this paper, a new empirical path loss model based on frequency, distance, and volumetric occupancy rate is generated at the 3.5 and 4.2 GHz in the scope of 5G frequency bands. This study aims to determine the effect of the volumetric occupancy rate on path loss depending on the foliage density of the trees in the pine forest area. Using 4.2 GHz and the effect of the volumetric occupancy rate contributes to the literature in terms of novelty. Both the reference measurements to generate a model and verification measurements to verify the proposed models are conducted in three different regions of the forest area with double ridged horn antennas. These regions of the artificial forest area consist of regularly sorted and identical pine trees. Root mean square error (RMSE) and R-squared values are calculated to evaluate the performance of the proposed model. For 3.5 and 4.2 GHz, while the RMSEs are 3.983 and 3.883, the values of R-squared are 0.967 and 0.963, respectively. Additionally, the results are compared with four path loss models which are commonly used in the forest area. The proposed one has the best performance among the other models with values 3.98 and 3.88 dB for 3.5 and 4.2 GHz.

中文翻译：

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基于5G频段松林体积占用率的新路径损耗模型

本文在 5G 频段范围内的 3.5 和 4.2 GHz 处生成了一个基于频率、距离和体积占用率的新经验路径损耗模型。本研究旨在确定体积占用率对路径损失的影响，具体取决于松林地区树木的树叶密度。使用 4.2 GHz 和体积占用率的影响有助于文献的新颖性。用于生成模型的参考测量和用于验证所提出模型的验证测量均在森林区域的三个不同区域中使用双脊喇叭天线进行。人工林区的这些区域由定期分类且相同的松树组成。均方根误差 (RMSE) 和R计算平方值以评估所提出模型的性能。对于 3.5 和 4.2 GHz，RMSE 分别为 3.983 和 3.883，R-squared 分别为 0.967 和 0.963。此外，将结果与森林地区常用的四种路径损耗模型进行了比较。建议的模型在其他模型中具有最佳性能，3.5 和 4.2 GHz 的值为 3.98 和 3.88 dB。