Extraction of Vibrating Features With Dual-Channel Fixed-Receiver Bistatic SAR

Strong ground clutter may submerge the signals of vibrating targets and bring great difficulties to extract their micro-Doppler (m-D) signatures. Furthermore, if the vibrating direction is perpendicular to the radar line of sight, its m-D would be very weak in the monostatic synthetic aperture radar (SAR). In this letter, a configuration of bistatic SAR with a dual-channel fixed receiver is presented to handle the two problems. The displaced phase center antenna technique is adopted to suppress the clutter and to reserve the signals of vibrating targets in the range-compressed data domain. Then, the fractional Fourier transform is utilized to compensate for the radar Doppler shift. Finally, the m-D feature of vibration can be extracted effectively by using time-frequency transform. The validity of the proposed method is evaluated with simulated data.