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Atmospheric turbulence is one of the main factors that influence the spread of laser communication in the atmosphere affect, which will change the random distribution of the refractive index of air, and affect the image quality of the beam through the atmosphere seriously. To study atmospheric turbulence in order to grasp changes in atmospheric turbulence, by taking the appropriate methods to control and reduce the effects of atmospheric turbulence on the beam quality. In addition to studying atmospheric turbulence using experimental methods and theoretical analysis. Numerical simulation is an effective means to study the problem of turbulence. Zernike polynomials were used to produce atmospheric turbulence phase screen in this article. The phase structure function and the atmospheric coherence length were used to check whether the atmospheric turbulence phase screen is right or not. Simulation results were studied show that, the atmospheric turbulence phase screen generated with Zernike polynomial method was consistent with the theoretical values in the low spatial frequency components, but, the simulation results had big difference with the theoretical values in the high spatial frequency components. The reason is that Zernike polynomials method has some limitations. In addition, the distribution of turbulence in the atmospheric turbulence phase screen can be changed by increasing the Zernike polynomials of orders or changing the receiving apertures, but which involves great and complex calculation. Therefore, in the specific application of the laser communication system, the best experimental program should be considered. Statistical properties of atmospheric turbulence phase can be described by the phase structure function. Therefore, the structure of the function will be used to determine the phase screen simulation phase screen is accurate. To give a better understanding of both methods the difference between simulation results, the simulation results of Zernike polynomials and power spectral inversion simulation results were compared. At last to give the corresponding power spectrum inversion method to simulate atmospheric turbulence phase screen simulation results and shows that the theory without making the introduction.
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