Wavenumber-domain SAR focusing from a nonuniform synthetic aperture

In the wavenumber-domain method of synthetic aperture radar (SAR) imaging, frequency-domain radar data are used to reconstruct a portion of the 2D Fourier transform of the scene, which is then inverted to create the image. The method suffers no inherent limits on aperture length or scene size. The concept is extended to the case where the synthetic aperture is not a straight line and the samples are unevenly spaced. An accumulation formula for wavenumber-domain reconstruction is derived and shown to be equivalent to earlier algorithms in the uniform-aperture case. It is then shown how data with three-dimensional irregularity in the aperture can be processed using height correction and mapping into the slant plane