Synthetic Aperture Radar or SAR is an imaging radar system that sends a microwave pulse to the surface of the earth and register the reflections from the earth's surface . On -board processing and compression of data obtained from the SAR is vital for image formation .The development of enabling technologies for space-borne SAR instruments have been a major focus of research and development during the last few years . At present the SAR systems provides only images and in future it will have to deliver dedicated information to each special user.