The forecast of rain rate and the accompanying attenuation is a crucial factor for analyzing the efficacy of a terrestrial-based ‘Free Space Optical’ communication technology. The optical beam in a terrestrial-based FSO communication system commonly propagates through open air, where it is susceptible to atmospheric hazards like rain, dust, fog, snow, etc., as a result, the optical beam is diminished by these hazards. In this paper, experimentation has been carried out in the developed artificial rain simulation chamber with a 980 nm Laser source. The considered modulated Laser beam propagates in the different rain rates that are generated by the artificial rain simulation chamber. The obtained optical power attenuation for wavelength (980 nm) is compared with other existing conventional models and developed a new rain attenuation model. With the research of optical power attenuation, the impact of various rain rates on communication channels has been investigated as well, and eventually, an optical power attenuation mitigation strategy known as the "Aperture Averaging" technique has been Introduced in the system. As a consequence, the optical link performance has been improved significantly in terms of received optical power, signal-to-noise ratio, bit error rate, etc., at different rain rate scenarios.

降雨率和随之而来的衰减的预测是分析地面“自由空间光”通信技术功效的关键因素。地面FSO通信系统中的光束通常在露天传播，容易受到雨、灰尘、雾、雪等大气危害的影响，导致光束因这些危害而减弱。本文在研制的人工降雨模拟室中采用980 nm激光源进行了实验。所考虑的调制激光束以人工降雨模拟室产生的不同降雨率传播。将获得的波长（980 nm）的光功率衰减与其他现有的传统模型进行比较，并开发了新的雨衰模型。通过对光功率衰减的研究，还研究了不同降雨率对通信信道的影响，最终在系统中引入了一种称为“孔径平均”技术的光功率衰减缓解策略。使得不同雨率场景下的光链路性能在接收光功率、信噪比、误码率等方面得到了显着提升。