Inverse synthetic aperture radar rotation velocity estimation based on phase slope difference of two prominent scatterers

In order to rescale an inverse synthetic aperture radar image into a homogeneous range cross-range domain, a novel method is proposed to estimate rotation velocity (RV) by exploiting the phase slope difference of two prominent scatterers on a complex image. Firstly, two prominent scatterers are automatically extracted in a range-Doppler image via watershed method. Subsequently, the signal obtained by the two scatterers is divided into two equal segments, each of which provides an estimation of the phase slope via phase unwrapping and the least-square fitting. Finally, the target RV can be estimated based on the difference of the two phase slopes. The proposed method can be implemented automatically and is more computationally efficient than the traditional methods. Finally, the results based on simulation data and real data are provided to demonstrate the effectiveness of the proposed method.