一种基于遗传算法的最小熵自聚焦方法

自聚焦算法是获得高质量合成孔径雷达SAR(Synthetic Aperture Radar)图像的重要步骤。针对复杂成像场景和复杂运动误差SAR自聚焦问题,提出一种基于遗传算法的最小熵自聚焦方法。方法通过高阶多项式函数拟合相位误差,以图像熵为代价函数,利用遗传算法最小化代价函数进而估计出相位误差,尤其适合于成像场景没有孤立强散射点、高阶相位误差不能忽略的自聚焦问题。仿真数据和实测数据处理结果证实算法的有效性。

Autofocus method based on the minimum-entropy criterion and Genetic Algorithm

Autofocus algorithm is significant to acquire high quality Synthetic Aperture Radar(SAR)images.In order to focus the SAR images with complex scene and complex motion error,this paper proposed an autofocus method based on the minimum-entropy criterion and genetic algorithm.In the method,the phase error in the SAR image is modeled by the polynomial and the entropy of the images is the cost function.Then the cost function is minimized by the genetic algorithm to obtain the optimal estimation of the phase error.The proposed method is especially suitable for the problems that there are less isolated prominent points and the high-order phase error is not negligible.The simulated data and the real data results have validated the method.