An Overview of the German Spaceborne X-Band SAR Program

An overview of the German spaceborne X-Band radar program will be presented in this paper. A view into the wide heritage of the German synthetic aperture radar (SAR) instruments and the paramount results obtained with the German X-band Missions will be provided. This paper will cover the Shuttle Imaging Radar missions (SIR-C/X-SAR) from 1994 and the Shuttle Radar Topography Mission (SRTM) from 2000, followed by the current missions TerraSAR-X from 2007 and TanDEM-X launched in 2010. Since then, the TanDEM-X mission is providing high-resolution X-band images for scientific, commercial and governmental applications. The milestones of the TanDEM-X mission, like the generation of a global, high-resolution digital elevation model of the Earth surface, will be presented. The paper will also discuss the challenges faced by the current mission under planning: High Resolution Wide Swath (HRWS), which is a very ambitious multi static SAR system exploiting the formation flight of one active main satellite and three smaller passive companion satellites. With HRWS, the MirrorSAR concept will be implemented in space for the first time. Finally, the future of the German SAR Program will be discussed.