Measurement of angle-of-arrival fluctuations over a real atmospheric turbulent path

The effect of angle-of-arrival fluctuation caused by atmospheric turbulence seriously influences the performance of the communication system in the free-space-optical communication. Variance of angle-of-arrival fluctuation is deduced from the theory of turbulent inner-and-outer scale. An experiment for angle-of-arrival fluctuation was carried out on 0.893 km line of sight link, 15000-frame grayscale images were grabbed by camera per 10 Min from 8:00 to 21:00 every day. The daily trends of the variance of angle-of-arrival fluctuation in different seasons and the effect on different wavelengths are achieved through this experiment. The experimental results indicate that the daily trends of the variance of angle-of-arrival fluctuation are different in different seasons, and the results measured at four wavelengths are similar. The results are in good agreement with the theoretical analysis.