Frequency-Domain Backprojection Algorithm for Synthetic Aperture Radar Imaging

A new frequency-domain backprojection method for processing synthetic aperture radar (SAR) data is presented. It forms SAR images by backprojecting the spectrum of the radar echo into the image wavenumber domain and is capable of fully correcting wavefront curvature and handling a general aperture geometry. From each reconstructed spectral pixel, information about the entire scene can be obtained, allowing the formation of interim lower resolution images during the processing. In addition, the method allows for an arbitrary sampling of the image spectrum. It forms SAR images by backprojecting the spectrum of the radar echo into the image wavenumber domain. Processing of simulated and experimental ultrawideband/widebeam SAR raw data demonstrates the efficacy of this new method.