一种基于复数相位屏的强激光大气传输仿真方案

针对传统实数相位屏法中只能表征湍流扰动而不能综合表征强激光在大气传输时导致的能量衰减、湍流扰动和非线性热晕效应等困难,提出一种基于复数相位屏表征的强激光大气传输仿真方案。该方案采用复数相位屏的实部和虚部分别表征衰减和湍流、热晕作用,其中基于能见度特征综合描述大气吸收和散射的衰减作用(复数相位屏的虚部),基于流体力学的密度扰动方程描述湍流和热晕的联合作用(复数相位屏的实部)。本方案具有光场全路径跟踪、易参数控制的优点,能够为实现远场强激光传输特性的评估提供更加完善的理论基础。仿真结果表明,该方案与实际外场测量参数更加一致,具备半实物仿真及参数评估的可行性。

A simulation scheme of high power laser atmospheric transmission based on complex phase screen

Aiming at the difficulties of traditional real phase screen method,which can only characterize turbulent disturbances but cannot comprehensively characterize the energy attenuation,turbulence disturbance and nonlinear thermal halo effect caused by strong lasers in the atmosphere,a simulation scheme of high power laser atmospheric transmission based on complex phase screen is proposed.The scheme solution uses the real and imaginary parts of the complex phase screen to characterize the attenuation,turbulence,and thermal halo effects respectively,in which visibility comprehensively describes the attenuation of atmospheric absorption and scattering(characterized by the imaginary part of the complex phase screen),and the density disturbance equation based on hydrodynamics describes the combined effect of turbulence and thermal halo(characterized by the real part of the complex phase screen).This solution has the advantages of full-field tracking of the optical field and easy parameter control,and can provide a more perfect theoretical basis for the evaluation of the transmission characteristics of the far-field intensity laser.The simulation results show that the scheme is more consistent with the actual field measurement parameters and has the feasibility of semi-physical simulation and parameter evaluation.