Research on Simulation Method of Atmospheric Turbulence Gamma-gamma Distribution Light Intensity Flicker Sequence

This article develops a theoretical framework for analyzing the temporal power spectral density (PSD) of irradiance fluctuations in Gaussian beams propagating through turbulent channels, based on spatial statistics theory and the frozen turbulence hypothesis. By integrating Rytov variance with phase screen theory, we derive an analytical expression for PSD under weak turbulence conditions. Furthermore, we employ an iterative Fourier-based stochastic process generation method to synthesize time-domain sequences that simultaneously satisfy both the derived PSD and the probability density function (PDF) characterized by the Gamma-Gamma distribution model of turbulence-induced intensity fluctuations. Simulation results demonstrate agreement between the generated sequences’ PSD characteristics and theoretical predictions, while the PDF accurately captures the statistical properties of light intensity in weak turbulence regimes. These findings validate the proposed method’s effectiveness and rigor in simulating the dynamic characteristics of optical intensity fluctuations in atmospheric turbulence.