Inverse synthetic aperture radar (ISAR) is a powerful means in target identifying, especially the target in the air, which can image the moving target. There is little study on modeling and resistance technique according to ISAR in China. This paper establishes a model of ISAR system, and then studies on some valid jamming technique. This will provide us the valid technique support on ISAR resistance equipment later.
Based on the difference between the forward-looking mode and the side-looking mode of spaceborne SAR system, this paper carefully analysis the Doppler properties of the forward-looking SAR (FSAR) mode: Doppler frequency and Doppler bandwidth etc; And point out the relation of the azimuth resolution of FSAR with carrier frequency, platform altitude and azimuth range in the surface of the Earth etc. and the azimuth resolution of FSAR isn't relate with antenna aperture length; And carefully discuss that these factors affect the azimuth resolution and that FSAR constrain to pulse repetition frequency and elevation angle; And explain the area of high resolution imaging and the request of the FSAR for the radar platform altitude.