TanDEM-X: DEM Calibration Concept

The TanDEM-X mission will derive a global digital elevation model (DEM) with satellite SAR interferometry. The aimed accuracies are an absolute height error of 10 m and a relative height error of 2 m for 90% of the data. This requires a correction of the elevation heights after interferometric processing by residual systematic DEM errors. The estimation and correction of these errors is called DEM calibration. This paper gives an overview of the DEM calibration strategy within the TanDEM-X mission. First, the error sources and their influence on the DEM are determined by a functional description. Then, a strategy for a new block adjustment of DEMs is set up and evaluated with simulated and real DEMs.