Low-frequency ultra-wideband synthetic aperture radar ground moving target imaging

A method for low-frequency ultra-wideband synthetic aperture radar (SAR) imaging of ground moving targets is proposed in this study. This method can deal with large range migration of the moving target. A first-order keystone transform is used to correct range walk (first-order range migration), and range curvature (second-order range migration) is compensated by using a second-order keystone transform. Both the first-order and second-order keystone transform parameters are independent of the motion parameters, so that this method can correct the range migration for all targets without knowing their velocity. The advantage of this method is that it can correct range curvature for all targets in one processing step, so that it is simple to implement. Simulation and experimental SAR data processing results are shown to demonstrate the validity of the proposed method.