Abstract:

To improve interferometric synthetic aperture radar (InSAR) imaging accuracy in the case of complex motion, a time-domain imaging method is exploited in this paper, and a novel algorithm based on echo projecting to the same space is proposed for InSAR imaging and interferogram extraction. The relationship between the backward projection Doppler phase compensation function and the interferogram is also analyzed. In this theme, the echoes of the different antennas are projected into the same imaging space, and then InSAR images are obtained by using the coherent echoes integration with a modified Doppler phase compensation function. The simulated and the experimental airborne InSAR results demonstrate that the proposed algorithm can improve the quality of InSAR imaging and interferogram compared with the conventional frequency-domain method. In addition, our algorithm can achieve both image registration and earth-flat effect removed during one procedure, which greatly simplifies the procedure of InSAR post-processing.

Key words: Interferometric synthetic aperture radar, Backward projection algorithm, Interferogram, Earth-flat effect, Image registration