3D surface reconstruction of layover areas in continuous terrain for multi-baseline SAR interferometry using a curve model

It has become a field of intensive research to exploit multi-baseline synthetic aperture radar (SAR) to solve layover effects. However, the traditional layover model is not suitable for 3D surface reconstruction in the case of continuous layover terrain for two major reasons. First, the continuous terrain cannot be precisely described by the traditional layover model. Second, the traditional layover model is formalized for a single range-azimuth resolution cell and does not take full advantage of the relationship among the neighbouring scatterers, producing ragged reconstruction results with large terrain bias. In order to solve these problems, we establish a new curve model and propose a corresponding layover solution method. Rather than rebuilding the layover area in each independent range-azimuth resolution cell, this method reconstructs it as a whole. It exploits both the multi-baseline SAR signal and a priori information of the continuous terrain to achieve better performance. In the final part of this article, the proposed method is applied to 3D surface reconstruction using simulated data and Phased Array type L-band Synthetic Aperture Radar (ALOS PALSAR) data in comparison with the traditional layover model-based solution method. It is found that the proposed method leads to considerable improvements with regard to accuracy and robustness.