Nadir echo properties, a study based on TerraSAR-X data

The paper investigates the properties of the Nadir echo. The analysis is based on two spaceborne SAR (Synthetic Aperture Radar) data sets, obtained with the TerraSAR-X system and provided by the German Aerospace Center (DLR). The data sets were commanded to contain strong Nadir echo and acquired over surfaces with homogeneous backscattering and topographic characteristics both in the swath of interest and in the Nadir region. The Nadir features in terms of duration, amplitude and phase and its behaviors, as point or distributed target, are studied and examined based on range compressed and image data analysis.