| Abstract: | Aimed at the severe azimuth variation caused by the ultralong synthetic aperture time and very large scene in geosynchronous synthetic aperture radar (GEOSAR), this paper develops an azimuth variation correction method for GEOSAR. The method firstly obtains the two-dimensional spectrum by the method of series reversion (MSR). The Doppler and azimuth positions of the point target in the two-dimensional spectrum are serious coupled. The singular value decomposition (SVD) can be introduced to separate the Doppler position from the position of the point target. Subsequently, Stolt interpolation is used twice to compensate the high-order phase terms. Thus, a focused scene is obtained. Finally, simulation for scene targets validate the proposed method. All the targets in the scene are focused well. |
