Extended Polar Format Algorithm (EPFA) for High-Resolution Highly Squinted SAR

The conventional polar format algorithm (CPFA) is widely used for synthetic aperture radar (SAR) because of its simple and efficient operations. However, due to wavefront curvature assumption, the CPFA’s depth-of-focus (DOF) extremely small, which greatly limits scene size, especially high-resolution highly squinted (HRHS) SAR. To solve this problem, an extended PFA (EPFA) proposed in study, re-deriving mapping functions by expanding range history into slant- cross-range components according forms real data storage. This allows full use storage data, CPFA cannot achieve large approximations introduced projection echo onto ground. error then analyzed eliminated using a space-variant phase compensation function. Due high accuracy expansion slant plane correction processing, EPFA has larger DOF than CPFA. also more suitable undulating terrains since it avoids ground performed Using comparative analyses simulated real-world images, results suggest that achieves better focusing effects particularly useful HRHS