Polar Format Algorithm for Spotlight Bistatic SAR with Arbitrary Geometry Configuration

This paper presents an effective Polar Format Algorithm (PFA) for spotlight bistatic synthetic aperture radar (SAR) with arbitrary geometry configuration. Nonuniform interpolation and resampling are adopted when converting raw data from polar coordinates to Cartesian coordinates according to the characteristics of raw data samples in spatial frequency space. Thus, the proposed algorithm avoids both rotation transformation and the calculation of azimuth compensation factor and thereby avoids the corresponding approximate error appeared in the conventional PFA. Meanwhile, the proposed algorithm inherits the character of decomposing 2-D interpolation to two 1-D interpolations from conventional PFA algorithm applied in monostatic SAR imaging. Therefore, the processing flow, computation efficiency and performance of the proposed algorithm are the same as those of conventional PFA for monostatic spotlight SAR. Point target simulations are provided to validate the proposed algorithm.