A study on the optimal step size of velocity for three-channel sar adaptive clutter suppression

The clutter suppression methods based on post-Doppler space time adaptive processing technology is a hot search topic in recent years. However, to coherently integrate a target's energy of each channel, these methods require searching target's velocities, which may introduce a large computation load. This paper proposes a method for calculating the optimal velocity search step of adaptive clutter suppression for the commonly used three-channel synthetic aperture radar (SAR) ground moving target indication (GMTI) systems. First, the signal models in the range Doppler domain are developed. Then, based on the fact that the signal-to-clutter-noise ratio loss of clutter suppression and the coherent integration gain loss are all introduced by the mismatch of the steer vector, the way to obtain the analytical expression for calculating the optimal velocity search step is developed. Experimental results validate the propose method.