Wireless links deployed in orchards often exhibit significant variability in the strength of the received signal that is not adequately captured by classical distance-based propagation models. In row-structured olive groves, signal attenuation differs markedly between along-row and cross-row propagation directions, leading to discrepancies when using omnidirectional propagation assumptions such as those adopted in the Free Space Path Loss (FSPL) model or ITU-R vegetation loss formulations. This paper proposes a topology-based propagation model that explicitly accounts for orchard layout and the relative positions of radio devices within the plantation structure. Experimental validation was conducted using LoRa technology operating at 868 MHz, and the results were compared with established models from the literature and with the proposed two-dimensional model. The proposed approach achieves a closer fit to measured RSSI data than conventional models, providing a more reliable basis for link budgeting and network planning in structured agricultural environments.

翻译：部署在果园中的无线链路常表现出显著的接收信号强度变异性，而经典的距离传播模型无法充分捕捉这一特性。在行状结构的橄榄园中，沿行与跨行传播方向的信号衰减存在显著差异，导致采用自由空间路径损耗（FSPL）模型或ITU-R植被损耗公式等全向传播假设时出现偏差。本文提出一种基于拓扑结构的传播模型，该模型明确考虑了果园布局及无线电设备在种植结构中的相对位置。实验验证采用工作于868 MHz的LoRa技术进行，并将结果与文献中的既有模型及本文提出的二维模型进行了比较。与常规模型相比，所提方法对实测RSSI数据的拟合更为精确，为结构化农业环境中的链路预算与网络规划提供了更可靠的依据。