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DEM calibration concept for TanDEM-X

The TanDEM-X mission [1] comprises two fully active synthetic aperture radar satellites operating in X-band. The primary goal of this mission is the derivation of a high-precision global Digital Elevation Model (DEM) according to HRTI level 3 quality [2]. This requires accurate calibration of the interferometric system parameters. Content of this paper is the development of a general concept for this calibration, which comprises the determination of instrument and baseline errors, an adjustment concept and the distribution of control points. This concept has a key incidence on mission aspects like the data acquisition plan and the data take adjustment procedure.