关键词: 多通道, 微动, 鬼影点, 干涉相位, 空域导向矢量, 杂波抑制

Abstract:

In addition to the bulk motion induced by constant velocity or uniform acceleration, the target or any structure on it may undergo micro-motion dynamics, such as mechanical rocking, vibrations, or rotations.The traditional range model approximated by second-order polynomials is not suitable for describing the range from a radar to the micro-motion targets.In this paper, combining with Paired Echo Principle and Range-Doppler(R-D) algorithm in synthetic aperture radar(SAR), we derive the vector expression which indicates the multi-channel echo of the ground moving micro-motion target in image domain on the basis of setting up its geometrical model, and analyze the azimuth defocusing in single-channel and the interferometric phase between channels induced by micro Doppler.The normalization of the amplitude of the echo of different ghost points and the correlation coefficient of the spatial steering vectors between each ghost point and clutter are introduced.The result of simulation demonstrates that making use of the ghost points to detect the ground moving target has good improvement factor in strong clutter background.

Key words: multi-channel, micro-motion, ghost points, interferometric phase, spatial steeringvector, clutter suppression