Digital processing of Seasat SAR data

The Synthetic Aperture Radar (SAR), on board the Seasat-A satellite, provides an all-weather imaging capability which should prove useful in a number of remote sensing applications. Unlike optical (Landsat) data, the SAR data requires extensive two-dimensional, space variant signal processing before an image is formed. This paper describes the signal processing operations in a digital processor which has been built to produce images from the Seasat-A SAR data. It describes the operations of real-to-complex data conversion, range compression via fast convolution, matrix transformation of 40 MB disk arrays, range cell migration correction, look extraction via bandpass filtering, azimuth compression via fast convolution, interpolation and detection.