激光大气传输室内模拟研究

Simulation of Laser Atmospheric Transmission in Laboratory

采用液晶空间光调制器在实验室内进行激光大气传输模拟研究。基于均匀各向同性的Kolmogorov湍流模型,利用Zernike多项式法生成静态相位屏,利用湍流冻结法生成r_0=0.1 m和r_0=0.05 m不同湍流强度下的动态湍流相位屏,并实时加载在液晶空间光调制器上。分析得到,接收端的对数光强概率密度分布趋近于正态分布,拟合确定系数均在0.9以上;到达角起伏方差分别为σ_1=7.1μrad和σ_2=7.49μrad且光斑中心集中在2个像素以内。实验结果与实际外场情况相符合,达到了较好的室内模拟效果.

The simulation of laser atmospheric transmission in laboratory has proceeded upon liquid crystal spatial light modulator. Zernike polynomial was used to produce static atmospheric turbulence phase screen based on isotropic Kolmogorov turbulence model. r0=0.1 m and r0=0.05 m are the atmospheric coherent length under the different turbulence intensity. Dynamic turbulence screen was based on the turbulence freezing method and was loaded in the driver of LC-SLM. Logarithmic intensity probability density distribution at the receiving terminal is close to normal distribution, the determinal coefficients is above 0.9. Arrival angle fluctuation variance is 7.1 urad and 7.49 urad, and the spot concentrated within 2 pixels. The results are consistent with the actual field and have achieved good effect in laboratory.