Performance of free-space optical link with wavelength diversity over exponentiated Weibull channel

In the free-space optical (FSO) channel, the optical signal suffers from irradiance and phase fluctuations due to the atmospheric turbulence that reduces the performance of the overall FSO system. In this paper, we have applied the wavelength diversity technique over the exponentiated Weibull channel to mitigate turbulence-induced fading. The source information was transmitted onto three carrier wavelengths of 1.55, 1.31, and 0.85 μm. At the receiver side, an optical combining scheme has been deployed to combine the multiple carriers. Mathematical expressions are derived for the calculation of the outage probability and bit error rate (BER) of the wavelength diversity system. Results are presented for the link lengths of 1.5 and 2.5 km with two different atmospheric turbulence conditions: moderate and strong. An overall improvement of 40 dB in outage probability and 30 dB in BER is achieved.