Measurement effect of visibility in experimental FSO system

Effect of visibility attenuation in FSO (Free Space Optics) has dominant impact on quality of received signal. Therefore, it is important to monitor this parameter, which is crucial for management of switching between optical communication and radio communication. The point of this paper includes design of measurement and analysis of results of visibility measurement on TUKE (Technical University of Kosice), where is FSO system deployed. Measurement of different weather parameters is running for this system on TUKE. Optical and radio channels are switching on the fly depending on base obtained by measurement of visibility values. We will describe possible methods of measurement of one weather parameter. This key parameter is visibility. Different measurement approaches provide different processing speeds. Faster and more accurate switching ensures stable system without disruption.