Adaptive optical amplification-based performance evaluation of an 8-channel DWDM-FSO system over diverse geographical terrains

Wavelength Division Multiplexing Free-Space Optics (WDM-FSO) systems increase last-mile, high-speed communication using multiple data channels simultaneously and transmitting over different light wavelengths through the air. In this paper, an 8-channel Wavelength Division Multiplexing (WDM) based Free Space Optical (FSO) communication system is proposed, and its performance is investigated under different atmospheric terrains. The proposed system works at 10 Gbps per channel over a 2 km distance in free space. The gain of Erbium-Doped Fiber Amplifier (EDFA) is optimized and applied separately for desert, mountain, urban, and coastal environments. Adaptive gain is used to maintain balanced link performance. The performance of the proposed system is evaluated in terms of received power, Q-factor, and Bit Error Rate (BER). The system is simulated in optisystem and the results indicate the gradual degradation of performance from desert to coastal environments, validating the effectiveness of adaptive gain control in mitigating atmospheric impairments.