Digital Elevation Model Generation using Ascending and Descending ERS-1/ERS-2 Tandem Data

In this study we show how ascending and descending ERS-1/ERS-2 tandem data can be used to generate a precise digital elevation model (DEM). In particular we present the advantages, for DEM generation, of combining ascending and descending interferometric data pairs with large baselines; unwrapping problems caused by the high fringe rates of these data are minimized by applying a flattening technique based on the use of a data pair with smaller baseline. The presented experiments carried out on the data of an area with steep topography (Etna volcano, Italy) confirm the potentiality of the proposed technique.