Spatial diversity-based FSO links under adverse weather conditions: performance analysis

This study demonstrates a significant reduction in the bit error rate (BER) within free space optical (FSO) communication systems, even in highly turbulent optical channels. The strategic application of spatial diversity techniques emphasizes the feasibility of achieving low BER values. In the presence of light fog, our system achieves a transmission range of 700 m, while medium and heavy fog conditions reduce it to 450 and 350 m, respectively. Under light dust conditions, the range extends to 350 m and decreases to 120 and 48 m in medium and heavy dust conditions. In a clear sky, our non-return-to-zero orbital angular momentum (OAM) multiplexing-based FSO system successfully transmits 40 Gb/s of data over a distance of 1500 m with reliable performance. The utilization of spatial diversity and beamforming techniques further enhances system reliability, making it robust even in challenging real-world scenarios. However, it is essential to address the impact of adverse weather conditions, such as fog and dust, by developing weather-resistant technologies for reliable FSO communication. While fog generally exhibits better performance, the significance of spatial diversity remains crucial in adverse conditions, encompassing both fog and dust weather factors. The integration of OAM beams and FSO technology holds promise for high-speed and efficient optical communication. This research addresses the mitigation of weather-induced fading through OAM multiplexing.