Improving DEMs using SAR interferometry

Interferometric synthetic aperture radar (InSAR) processing relies on phase unwrapping to convert phase to topographic height. Rather than processing the complete phase image to extract a digital elevation model (DEM), the authors take the approach of using existing coarse DEMs to estimate the baseline accurately and guide the phase unwrapping processing. They apply their algorithm to ERS Tandem Mission data to demonstrate a four-fold increase in DEM quality using an existing coarse DEM to aid in phase unwrapping and also to estimate the baseline.