A spectral diversity based approach for DEM reconstruction

In this letter, an approach based on spectral diversity and conventional Interferometric Synthetic Aperture Radar (InSAR) for Digital Elevation Model (DEM) reconstruction is proposed. Conventional InSAR technique often fails to correctly reconstruct the DEM due to the presence of discontinuities and/or interferometric noise. With the assistance of the spectral diversity method, the ill-posed phase-unwrapping can be regularized. Thus the capabilities of the conventional InSAR technique for DEM reconstruction can be notably improved. Comparing to the multi-channel InSAR technique, the proposed method requires less SAR images. Comparing to the multifrequency technique, the performance of the proposed method depends on the perpendicular or effective baseline and the ratio of the radar´s carry frequency to the bandwidth between the central frequencies of the two sub-looks; while the multifrequency technique depends more on the range bandwidth. Thus, the proposed method is more flexible than the multifrequency technique. The effectiveness of the proposed algorithm is validated by experimental results using real data.