Department of Electrical Engineering, Faculty of Engineering, Chiang Mai University, Chiang Mai 50200, Thailand.
Biomedical Engineering Institute, Chiang Mai University, Chiang Mai 50200, Thailand.
Sensors (Basel). 2023 Feb 24;23(5):2532. doi: 10.3390/s23052532.
Millimeter wave fixed wireless systems in future backhaul and access network applications can be affected by weather conditions. The losses caused by rain attenuation and antenna misalignment due to wind-induced vibrations have greater impacts on the link budget reduction at E-band frequencies and higher. The current International Telecommunications Union Radiocommunication Sector (ITU-R) recommendation has been widely used to estimate rain attenuation, and the recent Asia Pacific Telecommunity (APT) report provides the model to estimate the wind-induced attenuation. This article provides the first experimental study of the combined rain and wind effects in a tropical location using both models at a frequency in the E band (74.625 GHz) and a short distance of 150 m. In addition to using wind speeds for attenuation estimation, the setup also provides direct antenna inclination angle measurements using the accelerometer data. This solves the limitation of relying on the wind speed since the wind-induced loss is dependent on the inclination direction. The results show that the current ITU-R model can be used to estimate the attenuation of a short fixed wireless link under heavy rain, and the addition of wind attenuation via the APT model can estimate the worst-case link budget during high wind speeds.
毫米波固定无线系统在未来的回程和接入网络应用中可能会受到天气条件的影响。由于风致振动导致的雨衰减和天线失准引起的损耗,对 E 波段及更高频率的链路预算减少的影响更大。目前,国际电信联盟无线电通信部门(ITU-R)的建议已被广泛用于估计雨衰减,而最近的亚太电信共同体(APT)的报告则提供了用于估计风致衰减的模型。本文首次在热带地区使用这两种模型在 E 频段(74.625GHz)和 150 米短距离进行了综合雨风和风效应的实验研究。除了使用风速进行衰减估计外,该设置还使用加速度计数据提供了直接的天线倾斜角度测量。这解决了依赖风速的局限性,因为风致损耗取决于倾斜方向。结果表明,当前的 ITU-R 模型可用于估计大雨中短距离固定无线链路的衰减,而通过 APT 模型增加风衰减可以估计大风速下最坏情况的链路预算。