A novel range cell migration correction algorithm for highly squinted SAR imaging

Squint minimization processing (SMP) with a range-walk correction is widely used to simplify the range and azimuth coupling for highly squinted synthetic aperture radar (SAR) imaging. However, SMP destructs the azimuth shift invariance of conventional SAR transfer function, which severely degrades the range cell migration correction (RCMC) accuracy. A novel algorithm is proposed in this paper to removed the residual RCM for highly squinted airborne SAR with the subaperture (SA) processing, due to the analytic expression of the residual RCM in SA image domain. Real measured data sets validate the proposed algorithm could obtain a better focusing performance for highly squinted SAR imaging.