基于重叠子孔径极坐标算法的波前弯曲效应的补偿

Wavefront Curvature Compensation Based on Overlapped Subaperture Polar Format Algorithm

聚束SAR模式是获得高分辨率雷达图像的一种有效的方法.用经典的极坐标算法重建聚束SAR图像时,波前弯曲效应会导致远离图像中心处的点散焦.本文通过对波前弯曲产生的机理以及经典极坐标算法下空变相位误差的分析,提出了一种可以在成像过程中补偿波前弯曲效应的重叠子孔径极坐标算法,该算法可以有效的增大极坐标算法的成像面积,可以应用于P波段成像和超高分辨率成像中.

Spotlight SAR is an effective way to obtain high resolution radar imagery. The effect of the wavefront curvature will defocus the point far away from the imagery center by the classical polar format algorithm. We analyse the mechanism of wavefront curvature and space variant phase error in polar format algorithm, then present an overlapped sub-aperture polar format algorithm of the wavefront curvature correction during the course of SAR imaging, which can increase the imaging area for PFA algorithm and can be used in P band imaging and ultra high resolution imaging .