Spaceborne synthetic aperture radar(SAR) is a kind of modern high resolution sidelooking imaging radar. Making use of the techniques of the synthetic aperture
pulse compression and digital information processing
it obtains high resolution in azimuth direction and in range direction. In this paper
the present situation and development trend of spaceborne SAR are summarized. The main techniques of SAR are disscussed
which include spaceborns SAR patterns and systems
and information processing and imaging processing of SAR digital image. Finally
the imaging results using SEASAT-A satellite SAR raw data are provided.