摘要
阐述了差分光柱像运动激光雷达探测大气湍流廓线的基本原理,针对雷达现有Levenberg-Marquardt反演算法对高空湍流反演误差大的问题,提出了带不等式路径约束的反演新模型,并采用惩罚函数法处理该模型,通过增加高空湍流信息量,避免了非物理意义的反演解;同时为了减弱现有算法对初值和先验知识的依赖,进一步提出了基于遗传算法的初值寻优策略,能够将现有算法的初值定位在全局空间内。利用改进算法和现有算法数值仿真了典型的大气湍流廓线,并对合肥地区实测激光雷达数据进行了分析。结果表明,改进算法增强了迭代过程的全局搜索能力,对测量误差有较强的稳健性,能够有效提高反演精度和高空湍流的准确性,同时也加快了收敛速度。
The principle of differential column image motion light detection and ranging for acquiring atmospheric turbulence profile is described. Aiming at the large retrieval error in high-altitude turbulence of current LevenbergMarquardt inversion algorithm, a novel inversion model with inequality path constrained is developed and the penalty function method is used to handle this model, thereby an unphysical solution by adding the information of highaltitude turbulence is avoided. Furthermore, in order to weaken the current algorithm dependence on initial value and priori knowledge, a new optimization strategy based on genetic algorithm is presented to locate initial value of current algorithm in global variable space. Typical atmosphere turbulence profiles are simulated with the modified algorithm and the current algorithm. The measured lidar data in Hefei are also analyzed. Results show that the modified algorithm can enhance the global search capability of iteration process and perform strong robustness against measurement noise, improving the retrieval precision and accurate quantification of high-altitude turbulence effectively. Moreover, the modified algorithm accelerates the convergence.
出处
《光学学报》
EI
CAS
CSCD
北大核心
2016年第4期30-38,共9页
Acta Optica Sinica
基金
国家自然科学基金(41405014)