针对大气湍流对拉盖尔 -高斯光束的螺旋谱的影响，本文提出利用多相位屏法模拟拉盖尔 -高斯光束在大气湍流中的传输。采用傅里叶变换法模拟符合 non-Kolmogorov谱的大气随机相位屏，通过改变拓扑荷、光束波长、指数参数、折射率结构常数、湍流内尺度、外尺度等参数，对大气湍流的影响进行数值模拟。仿真结果表明，大气湍流会导致拉盖尔 -高斯光束的螺旋谱的弥散。而且，螺旋谱弥散与拓扑荷、波长、指数参数、折射率结构常数、内尺度、外尺度密切相关。

In order to study spiral spectrum spread after Laguerre-Gassian (LG) beam propagating through atmospheric turbulence, the method of multiple phase screen is proposed to simulate the transmission of LG beams carrying Orbital Angular Momentum (OAM) in atmospheric turbulence. Propagation of Laguerre-Gaussian beam through atmospheric turbulence is simulated using phase screen based on Fourier transform following the non-Kolmogorov spectrum and the effect induced by atmospheric turbulence is computed quantitatively for different topological charges, wavelengths, exponent parameters, structure constant of the refractive-index fluctuations, inner scales and outer scales. The simulation results show that atmospheric turbulence deteriorates spiral spectrum of LG beam. It is also shown that system performance is closely related to topological charge, wavelength, exponent parameters, structure constant of the refractive-index fluctuations, inner scales and outer scales.