Direct determination of the two dimensional image spectrum from raw synthetic aperture radar data

An algorithm is described which computes the two-dimensional Fourier transform of a synthetic aperture radar image. This method is intended to replace the whole SAR processing and the two-dimensional Fourier transformation by a specialized processing scheme which, in terms of computational speed and complexity, will be of the order of a single two-dimensional autocorrelation. This processing approach is applied to the estimation of the wave directional spectrum from the raw data of the SAR sensor of SEASAT-1.