TerraSAR-L is the new imaging radar mission of the European Space Agency, with Astrium Ltd. acting as Prime Contractor. The platform, based on the novel Snapdragon concept, is built around the active phase array antenna of the L-band Synthetic Aperture Radar (L-SAR). Specification of the L-SAR has been guided by careful analysis of the product requirements resulting in a robust baseline design with appropriate margins.
Besides providing commercial geo-information products, TerraSAR-L will contribute to the Global Monitoring for Environment and Security (GMES) initiative and serve the scientific user community. Major application areas are: Kyoto inventory and wetland monitoring, solid earth science including seismic and volcanic activity as well as land slides and subsidence, land cover classification in different levels of detail and marine applications. The TerraSAR-L operations strategy is based on a long-term systematic and repetitive acquisition scenario to ensure consistent data archives and to maximise the exploitation of this very powerful SAR system.
The Infoterra/TerraSAR initiative started as an industrial concept to provide X- and L-band SAR data products from a pair of spacecraft in Sun-synchronous orbit. The mission was proposed by the BNSC and DLR for implementation as an element of the ESA’s Earth Watch programme. The X-band element evolved into a German national programme
between DLR and Astrium GmbH, whereas the TerraSAR-L System has become the subject of a phase B consolidation study led by Astrium Ltd. in the UK and involves companies in several other ESA member states.
The TerraSAR-L System comprises a single spacecraft carrying a large, fully polarimetric L-band SAR, and a ground segment architecture that will re-use existing facilities and technologies as much as possible. The service segment, sized to meet the mission’s requirements, complements this. Besides having a commercial role for the provision of geoinformation products, the TerraSAR-L System will serve the scientific user community, particularly with regard to Earth science use, and for contributions to the GMES initiative. Specification of the L-SAR instrument and ground segment performances has been guided by careful analysis of the product requirements so as to meet the user
communities’ needs without over-design of the hardware.
Extensive trade-off studies have proven that the L-band spacecraft should adopt the innovative 'Snapdragon’ configuration, minimizing technical risk and cost whilst offering comfortable design margins. The TerraSAR Consolidation has commenced and will involve a wide industrial community in the specification and definition for the
TerraSAR-L System. Key instrument and Snapdragon risk reduction activities are well advanced under ESA contract, with completion expected in 2004.