ACCURACY ANALYSIS OF SRTM HEIGHT MODELS

An accuracy analysis of the digital height models from SRTM C-band over large areas has been carried out. Statewide Digital Elevation Models (DEMs) acquired using digital photogrammetric techniques and LIDAR were used as base for the analysis. Classification of the terrain based on land use/land cover and topographic characteristics was previously carried out for a detailed analysis showing the dependency upon object characteristics. The horizontal relation between the reference DEM and the SRTM height data have been determined after datum transformation by an adjustment of shift parameters separately for sub-areas indicating also the horizontal accuracy of the SRTM data. The SRTM height models are showing the visible surface – a Digital Situation Model (DSM). The possibilities of a filtering from DSM to DEM are analyzed. Special care was taken for the filled voids of the SRTM data.