Performance evaluation of Free Space optical link at 650nm using red laser under rain conditions using experimental set-up

Free Space Optics (FSO) communication is a demanding efficient wireless technology which have been accepted due to its low power and mass requirements, high data rates and unlicensed spectrum. Atmospheric disturbances have a significant impact on performance of FSO Link which causes to degrade the laser beam. In this paper, the communication of 650nm red laser through free space is studied by experimentally. The FSO link can tolerate maximum attenuation up to 19.79 dB/km at the rain rate of 2.716mm/minute. The effect of rain on the visible light communication has taken three different cases of rain attenuation on the FSO link that depends on the rain drop sizes.