A New Sidelobe Suppression Algorithm for SAR Images with an Arbituary Doppler Centroid

Abstract

Synthetic aperture radar (SAR) imagery usually requires sidelobe control or apodization, via weighting the frequency domain aperture. This is important when the target scene contains such objects as ships or buildings, which have very large radar cross sections. Much effort has been made to control sidelobes and many apodization methods, like the spatial variant apodization (SVA), are presented. However, these algorithms ignore the Doppler centroid, which may not be zero when the radar has a radial velocity. In this paper, a new algorithm is presented to suppress the sidelobes in SAR images. This algorithm is similar to the SVA method. However, since it considers the nonzero Doppler centroid, this algorithm has better performance than the original SVA method. The results of simulated data and field data indicate the advantage of the algorithm over the traditional SVA algorithm.