Modeling statistics of rain attenuation affecting FSO links: A case study

This work presents a methodology to estimate statistics of rain attenuation affecting short (up to approximately 500 m) Free Space Optics (FSO) links. The model, which takes into account the effects of the Drop Size Distribution (DSD) and only requires as input the local mean yearly cumulated rain, is applied to derive predictions for the city of Hyderabad, Pakistan. Specifically, the local outage probability is calculated for a FSO link of 200 and 500 m, respectively. The methodology might help engineers in designing short FSO links in fog-free regions by identifying the power margin required to counteract rain attenuation in order to guarantee a target link availability.