High-Resolution DEM generation by nonlocal filtering of TanDEM-X interferograms

Abstract

We present a nonlocal synthetic aperture radar interferometry (InSAR) filter for TanDEM-X bistatic strip map interferograms, with the goal of generating a digital elevation model (DEM) from TanDEM-X interferograms with a higher resolution and accuracy than the default product. The filter is especially tuned for DEM generation as it takes into account the local topography and phase heterogeneity. Simulations and initial real data tests confirm that it significantly outperforms boxcar averaging, the currently employed phase denoising filter in the TanDEM-X processing chain, and circumvents some of the shortcomings of existing nonlocal filters.