The Amplitude and Phase Characteristics of Rotating Target’s in The Three Apertures InSAR

In this paper, the time-frequency and Doppler models of a rotating target are established firstly, and then its SAR image characteristic can be derived from the Doppler-domain. Finally the perspectives of physical significance of Displaced Phase Centre Antenna and Along-Track Interferometry technologies which are used in the three apertures InSAR to achieve clutter cancellation and velocity estimation are analyzed. By combining those conclusions come from the former steps, the amplitude and the interferometric phase characteristics of the rotating target’s in the three apertures InSAR are easily derived separately. It shows that this method is more intuitive and simple than traditional method by establishing approximate slant-range model of rotation target. Those conclusions are verified by some simulations. It also presents that an error GMTI result may occur resulting from phase wrapping when InSAR probes rotating targets. This paper will be a pilot study on micro-motion targets under the circumstances of multi-channel SAR, and proves that the micro-motion type jamming can adverse effect GMTI.