Calibration Performance of the TerraSAR-X and TanDEM-X Satellites since Launch

The TerraSAR-X and the TanDEM-X satellite produce high quality SAR images for a number of scientific and commercial applications. To guarantee the stability of the high accurate SAR products both systems are permanently monitored over the full life time. The intention of this paper is to present the latest results of Long-Term System Monitoring (LTSM) to demonstrate the remarkable performance of both systems since launch. The study focuses on radiometric accuracy and stability that include the gain and phase properties of the T/R modules, as well as the antenna pattern checked by evaluating uniformly distributed targets and radiometric stability over permanently deployed point targets