GMT Imaging of Synthetic Aperture Radar Based on Spectra Recognition

Synthetic aperture radar (SAR) is an all-weather high resolution imaging radar. When there is a moving target, the target is often submerged by the surrounding strong background. Therefore, it is very hard to detect the moving target. In this paper, we proposed a new ground moving target (GMT) imaging method based on spectra recognition. Firstly, the velocity and position of the moving target is obtained based on GMTI method. And the spectra of GMT is recognized. Then, the squint angle and the pulse repeat frequency (PRF) is well designed, which can guarantee that the clutter and GMT spectra can be separated clearly. Unpolluted GMT spectra is obtained by a band-pass filter. Lastly, for GMT SAR imaging, a moving target is regarded as a steady target under an equivalent geometry with a new equivalent squint angle and a new SAR platform velocity. The SAR image is obtained with the range-Doppler algorithm. The experimental results obtained by simulation show the feasibility of the proposed method.