Performance Evaluation under Different Fog Conditions for FSO Link

Free space optics is a technology in the field of communication in which light is propagated to send and receive information from one point to another in free space. FSO is compared with optical fiber cable as both use light to propagate information, the only difference is that in FSO light propagates through free space atmosphere. The main drawback of FSO lies in the fact that both internal as well as external parameters effect the performance of the FSO link. Internal parameters like wavelength, optical power, frequency etc and external parameters like visibility, scintillation, cloud conditions, fog conditions etc. This paper presents a detailed survey on attenuation due to variation in visibility range caused by different fog conditions of the Delhi, Safdarjung region. Kim's model is used to calculate attenuation for three specific months (January, February and December) for seven consecutive years starting from 2013 to 2019. The wavelength is also varied between 850nm,1300nm and 1550nm in order to find the most appropriate wavelength for transmission of signal.