Abstract:

In inverse synthetic aperture radar (ISAR) imaging, the rotation angle of object is required to remove the phenomena of the migration through resolution cell and scale the cross range of the image. The phase character of the Dechirp data is analyzed in detail and a new method based on spectral envelope correlation for estimating the rotation angle is proposed. Compared with the phase cancellation method, the proposed algorithm does not needs to know the priori information of the target such as its size, and has better robustness. The coefficient of the quadratic phase term based on the correlation of the shorttime Fourier transform (STFT) data is estimated, and the weighted linear least squares algorithm is used to improve the exactness of the result. Finally, simulation results verify the effectiveness of the method.