Performance of BPSK-FSO Communication Over Turbulence and Fog Attenuation

Free space optical communication is a technology that uses optical signals to transmit data between transmitters and receivers. In this paper, we analyze the performance of optical wireless transmission using heterodyne binary phase-shift keying (BPSK) modulation. The system is operating under various atmospheric channel effects. More precisely, the combined effects of atmospheric turbulence and fog. Atmospheric turbulence induces intensity fluctuations, and fog causes losses in signal power. To evaluate the optical wireless performances, we derived a mathematical expression of the bit error rate (BER) that combines fog attenuation and turbulence fading. We used a gamma-gamma distribution for modeling atmospheric turbulence fading and Meijer’s G-function for approximating complex calculus. We carried out numerical simulations of the bit error rate for different link distances, Rytov variances, and transmitted powers. The results show that the effects of turbulence and fog are very important for strong turbulence, and these effects limit link transmission. According to the simulation results, it is clear that we can decrease the BER and increase the link communication by raising transmitted power.