Micro-doppler extraction of vibrating target based on dual-channel ATI technique in SAR

Aiming at extracting the time-varying micro-Doppler feature of the ground vibrating target within ground clutter environment, the method of micro-Doppler extraction based on dual-channel ATI technique is presented. The ATI technique is utilized to suppress the ground clutter, and preserve the interferometric signal of the vibrating target in the raw data domain, which is presented as a straight line along the azimuth direction. According to this feature, we can find out which range cell the signal locates at, and then by taking the time derivative of its phase, the micro-Doppler modulation can be obtained. Compared to the single-channel situation, there is no need to compensate for the Doppler shift caused by the radar´s translation in advance, and we can obtain the micro-Doppler feature induced by the vibration in any direction, which will help to reduce the computation burden and improve the target detectability. Simulated results verify the validity of the proposed method.