Performance analysis of CO-OFDM FSO system under different weather conditions

FSO (free space optical communication) is less costly and use frequency spectrum which is license free. In this paper, to send the electrical signal in the form of optical signal and reconstruct it in electrical signal we will use coherent detection technique. We also used OFDM techniques, which mitigate the consequence of frequency selected fading and the inter-channel interference (ICI) effectively. The presence of motes, such as fog and clouds in the propagation channel introduces spatial and angular dispersion to the transmitted light signals. Data rate of transmission depend on dispersion due to channel. So we use coherent orthogonal frequency division multiplexing (CO-OFDM) technique to achieve maximum rang for given signal power. In this paper we have justified performance of CO-OFDM FSO system in different weather condition at data rate 2Gbps and 5Gbps.