Dynamic baseline millimeter-wave InSAR imaging and high inversion based on back-projection algorithm

Due to uncertainties of the platform motion, the trajectory of airborne millimeter-wave interferometric synthetic aperture radar (MMW-InSAR) usually demonstrates highly non-linear, which cause dynamic baseline to height inversion. In such cases, traditional InSAR methods may suffer from serval difficulties for imaging and height inversion. In this paper, a novel back projection imaging algorithm via terrain height prediction, named as THP-BP algorithm, is proposed. In this theme, an iterated approximating method is used. In each iteration, the MMW-InSAR data is projected into an estimated terrain surface to producing interferogram, and then the terrain height of the observed scene can be predicted via minimizing of the interferometric phase value of MMW-InSAR. The effectiveness of the proposed method is testified by both simulation and experiment data, the results demonstrate that it can improve the quality of both image focusing and height inversion compared with conventional BP algorithm.