嵌入遗传算法的顺轨干涉SAR海表流场反演新方法

New method for ocean surface current retrieval by along-track interferometric SAR based on genetic algorithm

顺轨干涉SAR海表流场探测技术研究对于实现流场探测的全球化、精细化具有重要作用。为了提高海表流场迭代收敛速度和参数反演精度,依据校正系数的参数特点构建适应度函数的约束关系,将校正系数设计问题转化为仿真干涉相位与实测干涉相位差和雷达、平台参数约束条件下的比例因子选择问题,进而设计遗传算法计算校正系数的技术方法,并嵌入海表流场迭代反演算法,从而构建一种反演新方法。星载SAR数据仿真实验结果表明:海表流向反演的均方根误差优于10.0°,海表流速的均方根误差优于0.1 m/s,这符合海表流场反演精度要求。改进的海表流场反演算法可减少2~3次迭代,有效提高了反演效率。研究对于提高顺轨干涉SAR海表流场探测的实效性和准确性具有重要意义。

The research on ocean surface current sounding by along-track interferometric SAR is an important role in realizing the globalization and refinement of current information.In order to improve the iteration convergence speed and parameter retrieval accuracy of ocean surface current,the correction coefficient design problem was transformed into scale factor selection problem under constraints of the phase difference between the simulated interference phase and the measured phase difference,and radar,and platform parameter,according to the parameter characteristics of the correction coefficient to construct the constraint relation of the fitness function.The technical method was designed to calculate the correction coefficient by genetic algorithm,which was embedded in the iterative retrieval algorithm to construct a new retrieval method.The results of spaceborne SAR data simulation showed that the RMSE of current direction is better than 10.0°,and the RMSE of current velocity is better than 0.1 m/s,which meets the requirements of ocean surface current retrieval accuracy.The improved ocean surface current retrieval algorithm can reduce the number of iterations by 2 to 3,which effectively improves the retrieval efficiency.The research is of great significance to improving the effectiveness and accuracy of ocean surface current sounding by along-track interferometric SAR.