Signal amplitude and phase equalization technique for free space optical communications

We propose a technique for equalizing the amplitude and phase fluctuations of the distorted signal in free space optical (FSO) communications. The technique exploits the dynamic characteristics of a semiconductor optical amplifier (SOA) together with the interferometric properties of a cascaded optical delay interferometer (ODI). By conducting numerical simulation we have investigated the impact of the SOA and ODI critical operating parameters on the performance of the FSO communication system. The obtained results confirm the feasibility of the scheme and its capability of efficiently mitigating the amplitude and phase variations, as quantified by the achievement of acceptable metrics. Thus the technique can enhance the robustness of FSO links against atmospheric impairments, including scintillation, and allow for better quality and more reliable interconnections.