Design and Performance of the TanDEM-X T/R Modules

The paper will discuss the design, the main features and the performance of the T/R Modules for the TanDEM-X (TerraSAR-X add-on for Digital Elevation Measurements) mission. The TanDEM-X T/R Module is an efficient reproduction of the TerraSAR-X T/R Module with slight optimisations for an enhanced producibility at the EADS Microwave Factory in Ulm. The TanDEM-X T/R Module consists of the main unit SMTR(R) Module ('Standardised Modular T/R Module'), the 'Frontend Electronics Unit' and 'Control Electronics' in one common housing. The relevant subcomponents are briefly described in this paper. Main features of the TanDEM-X T/R Modules are high precision of amplitude and phase adjustment over a temperature range from -20deg C to +60deg C, polarimetric operation (HH, VV, HV, VH) and switching of polarisation from pulse to pulse, high overall efficiency, high reliability over the complete mission lifetime, low mass, affordable cost and a uniform T/R Module performance. Also the latest measurement results of the first TanDEM-X T/R Modules will be discussed in the paper.