DOI: 10.3724/SP.J.1146.2012.01437

Journal of Electronics & Information Technology (电子与信息学报) 2013/35:12 PP.2843-2849

Study on Squint Sliding Spotlight Mode SAR Imaging

When the sliding spotlight mode SAR works in spaceborne squint case or airborne high-squint high- resolution case, the coupling between range and azimuth rises rapidly. It leads to a new two-dimensional (2-D) spectrum skew phenomenon. The skew extend the azimuth spectrum and enlarge the Doppler bandwidth, which causes a new azimuth spectral folding effect. The folding can not be eliminated by the conventional two-step processing algorithm. In this paper, a modified two-step processing algorithm is proposed. Efficiently implemented without large zero padding, it eliminates the effect of the 2-D spectrum skew. Therefore, the algorithm can process the data of squint sliding spotlight mode efficiently. The processing flow of the algorithm is described in detail, and compared with the conventional two-step processing algorithm. Finally, experiments on simulated and real data validate the effectiveness of the proposed algorithm in squint sliding spotlight case.

Key words:SAR,Squint sliding spotlight,Two-step processing algorithm,2-D spectrum skew,Appended bandwidth,Deskewing

ReleaseDate:2014-07-21 17:04:27