160 Gbaud Nyquist optical time-division multiplexed signal transmission through 4 km emulated free-space turbulence link

An emulation method using Fourier transform and Fresnel theory is utilized to characterize beam propagation through free-space turbulence link. A spatial light modulator is utilized for the generation of phase screens to emulate the turbulence effects based on Fourier transform method. Fresnel theory based scaling is used to emulate the long-range turbulent propagation. Simulation results of 4 km beam propagation are firstly provided based on the method. A single 160 Gbaud Nyquist channel transmission experiment under 4 km emulated free-space turbulence link is then demonstrated. 100 phase screen statuses are generated through the spatial light modulator for 7 turbulence strengths. BER distributions under these statuses are measured to characterize the turbulence influence on the signal. Turbulence induced power fluctuation is found to be main reason of performance deterioration.