基于快速傅里叶变换的高精度湍流相位屏模拟  

High-precision turbulence phase screen simulation based on fast Fourier transform

作　　者：向劲松[1] 温掌民 吕心浩 XIANG Jingsong;WEN Zhangmin;LYU Xinhao(School of Communication and Information Engineering,Chongqing University of Posts and Telecommunications,Chongqing 400065,China)

机构地区：[1]重庆邮电大学通信与信息工程学院,重庆400065

出　　处：《激光杂志》2023年第10期10-13,共4页Laser Journal

基　　金：国家自然科学基金项目(No.61571072,61371096)。

摘　　要：在基于快速傅里叶变换的功率谱反演法模拟湍流相位屏时,可以用相位自相关矩阵的离散傅里叶变换得到的湍流离散功率谱代替理论功率谱。这种操作避免了标准FFT方法中低频和高频分量欠采样的缺点。但由自相关函数经傅立叶变换得到的离散功率谱中存在负值,这些负值会导致模拟误差。针对此问题,提出了一种简单、精确的大气湍流相位屏模拟方法。通过将离散功率谱中的负值加权到相邻正值的方式来补偿残余误差。仿真结果表明,最大相对误差可以减小到<0.00065%,比其他基于FFT的相位屏误差小两个数量级。In the simulation of turbulent phase screen,it is proved effective to replace the theoretical power spectrum with the turbulent discrete power spectrum obtained by the discrete Fourier transform of the phase autocorrelation matrix.This operation avoids the drawbacks of undersampling of low-and high-frequency components in standard FFT methods.However,negative values present in the discrete power spectrum lead to analog errors.On this basis,a simple and accurate atmospheric turbulence phase screen simulation method is proposed.The residual error in the discrete power spectrum is compensated by redistributing between the negative value in the discrete power spectrum and the adjacent positive value.The simulation results show that the maximum relative error can be reduced to<0.00065%,which is two orders of magnitude smaller than any other FFT-based phase screen.In addition,the proposed method also has the advantages of simple implementation and easy to understand.

关 键 词：大气光学 大气湍流 相位屏 光通信 

分 类 号：TN249[电子电信—物理电子学]