Experimental Study on Phase Scintillation of Optical Transmission in Atmospheric Turbulence

The propagation of a beam in atmospheric turbulence causes phase fluctuations due to random variations in the atmospheric refractive index, leading to wavefront distortions. This paper analyzes the mechanisms of wavefront phase changes caused by atmospheric turbulence under different weather conditions and transmission distances. Local wavefront distortions are analyzed using Gaussian curvature, and wavefront distortions are assessed using peak-to-valley values, root mean square values, and the mean square error of the wavefront distortions. Additionally, the effects of different wavelengths and temperatures on wavefront distortions are studied. The experimental results show that the positive and negative Gaussian curvature peak values decrease in the order of snowy day (0.530, −0.850) μm−1, heavy rain (0.345, −0.447) μm−1, dust storm (0.412, −0.057) μm−1, light rain (0.297, −2.75 × 10−3) μm−1, sunny (0.154, −0.3 × 10−3) μm−1, and cloudy (0.107, −0.1 × 10−3) μm−1, with local distortions also decreasing in this order. The peak-to-valley values, root mean square values, and mean square error of the wavefront distortions decrease in the order of heavy rain (129.41 μm, 31.82 μm, 55.18 μm2), dust storm (74.1 μm, 18.84 μm, 51.40 μm2), snowy day (72.09 μm, 17.50 μm, 49.49 μm2), light rain (70.03 μm, 17.11 μm, 37.69 μm2), sunny (57.23 μm, 16.50 μm, 21.84 μm2), and cloudy (52.8 μm, 16.12 μm, 14.40 μm2). Shorter wavelengths exhibit greater phase fluctuations than longer wavelengths, and the degree of distortion increases with temperature. This study lays a theoretical foundation and provides experimental evidence for optical transmission in atmospheric turbulence.