1. A scalable range migration processing method for use in generating synthetic aperture radar image, comprising the steps of: inputting video phase history data for processing derived from a synthetic aperture radar that corresponds to a two-dimensional array of complex-valued input data, comprised of pulses by samples; processing the video phase history data using an along-track Fourier transform, to convert the input video phase history data to wavenumber space; processing the data using a phase adjustment to apply a predetermined phase adjustment function to the data; processing the data using a global matrix transpose to rearrange the data to produce values of range for a fixed value of azimuth; processing the data using range subband processing to produce range pixels; processing the data using a global matrix transpose to rearrange the data to produce values of azimuth for a fixed value of range; processing the data using azimuth subband processing to produce azimuth pixels; and outputting image data to form a synthetic aperture radar image.