对基于聚焦光束后向散射到达角起伏的湍流测量进行了数值模拟.通过近轴标量波动方程和分形相屏算法,提出了聚焦光束二次传输的数值模型,分别就固定点信标光源和聚焦光束后向散射的到达角起伏方差的统计特征进行了分析,并取得了很好的相关性,得出了可以从聚焦光束的回波图像信号里提取大气湍流信息的结论.讨论了聚焦距离对固定点光源和回波光束的到达角起伏方差相似度的影响.

A method of measuring the atmospheric turbulence based on the arrival angle fluctuation of a focused laser beam backscattering was numerically simulated.Based on the paraxial scalar wave equation and a fractal phase-screen algorithm a simu-lation model for the focused laser beam propagating along a fold path was proposed.With a constant Fried length,the arrival angle fluctuation variance was analyzed between the focused laser beam backscattering and the fixed point-source as reference beacon.A relatively high correlation between them was obtained.The simulation results were verified by experimental data.