提出一种基于多阶频率栅格划分的子谐波方法用于湍流相位屏的构造.通过对相位屏频域空间划分多阶频率栅格，并将每一阶的频率栅格进行更进一步精细子划分，补偿对湍流谱贡献最多的低频范围频率分量.采用大气湍流的相位结构函数和功率谱分析所构造相位屏的准确度.仿真结果表明：由所构造相位屏得到的相位结构函数与由湍流谱直接计算得到的理论值之间的偏差随着频率栅格总阶数M、每一阶的频率栅格点数目N′x和N′y的增大而减小，对每一组M、N′x、N′y的取值，子划分前的频率间隔Δf1有一最佳值；当选取M=3、N′x=N′y=3、Δf1=2 m-1时，所构造的相位屏的相位结构函数和功率谱与理论十分接近；所产生的随机相位屏的整体倾斜反映了低频成分的准确采样.

A subharmonic method was proposed based on the multi-order frequency grids dividing for the generation of the turbulent phase screen to compensate the low frequency components. Frequency grids were divided by multiple orders in the frequency domain of phase screen, and the frequency grids of each order were further finely subdivided, and then the frequency components in low frequency range which contribute the most to the turbulent spectrum could be compensated sufficiently. The phase structure function and the power spectrum of atmospheric turbulence were used to analyze the accuracy of the generated phase screen. Simulation results show that the discrepancy between the phase structure function derived from the generated phase screen and the theoretical value directly calculated from the turbulent spectrum is decreased by the increasing of the total number of frequency grid orders M, and frequency grid point number of each order N′xand N′y. For every group of M, N′xand N′y, there is an optimum value for frequency space before subdividing Δf1. By selecting M = 3, N′x=N′y=3 and Δf1=2 m-1, the phase structure function and the power spectrum of the screen can be quite closely to theory. The overall slope in the generated random phase screen reflects an accurate sampling of the low frequency components.