Study On The Characteristic Of Gaussian-beam Propagation In The Atmospheric Turbulence

In this paper, the fundamental theory for the optical Gaussian beam wavepropagation in the atmospheric turbulence is introduced, the different order-thstatistics moments of optical wave propagation in random media are derived.According to the modified Rytov method for the optical wave propagation and withconsidering the effect of the turbulence spectrum model with zero and non-zero innerscale in addition to the finite outer scale, the solution to the scintillation index as afunction of the Rytov variance is obtained from weak to strong fluctuation regions forGaussian beam propagation along the horizontal path. Based on the theory of opticalwave propagation in the slant path and the ITU-R turbulence structure constant modelwhich is altitude dependent, the modified Rytov method is extended to thepropagation in the slant path and the formula of scintillation index for Gaussian beampropagation is obtained, the influence of different altitudes, different sizes of the innerand outer scale of the turbulence on the scintillation index is discussed, the numericalresults are compared and verified with the experimental data. Finally, the Markovapproximation and the theory of high order-th statistics moment is applied to thewander effects of the Gaussian beam propagation in atmospheric turbulence, theformula of the wander for Gaussian beam propagation without/with considering theouter-scale is obtained, and the numerical result of the wander is present anddiscussed for the Gaussian beam propagation along the horizontal path.