The ordinary full-aperture SAR imaging algorithms are inapplicable to focus high squint diving SAR subaperture data due to its property of vertical velocity which brings variance in azimuth. Based on the equivalent squint model and the characteristic of subaperture imaging, this paper explores a Frequency Phase Filtering Algorithm (FPFA) to implement high squint SAR subaperture data focusing. The innovative idea is the introduced filtering phase in the azimuth frequency domain in order to eliminate the azimuth dependence. Finally, the equivalent squint model causes the geometric deformation; due to this issue, a modified inverse-projection method corresponding to FPFA is proposed to get the final image without deformation. The simulation results and raw data processing validate the effectiveness of the proposed method.
李震宇,梁毅,邢孟道,保铮. 一种俯冲段子孔径SAR大斜视成像及几何校正方法[J]. 电子与信息学报, 2015, 37(8): 1814-1820.
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