Sentinel-1 SAR Antenna Thermal Design and Verification Approach 2009-01-2351
The Sentinel-1 Mission is part of the Global Monitoring for Environment and Security (GMES) initiative whose overall objective is to support Europe's goals regarding sustainable development and global governance of the environment by providing timely and quality data, information, services and knowledge. The Sentinel-1 satellite is commissioned by ESA with Thales Alenia Space Italy as prime contractor and Astrium Germany as subcontractor for the Sentinel-1 SAR instrument.
Sentinel-1 is an imaging radar mission at C-band aimed at providing continuity of data for user services. In particular, Sentinel-1 is aimed at providing data to the sea ice zones and the arctic environment, to surveillance of marine environment (wind speed, oil spill and ship detection) to monitoring and mapping land surfaces, and mapping in support of humanitarian aid in crisis situations.
The Sentinel-1 SAR antenna is a large foldable planar phased array antenna which is formed by a centre panel and two antenna side wings. Once deployed, the antenna is more than 12 m long with a width of 1 m. Its mass is about 900 kg. The Sentinel-1 SAR antenna thermal control relies mainly on a passive design (MLI, radiating surfaces) assisted by a software controlled heater system. An appropriate number of heater and thermistor lines is provided by the S/C bus to cope with all nominal operation and survival modes.
The Sentinel-1 programme is currently in Phase C. The design is largely settled and the SAR Antenna CDR thermal analysis campaign is about to start. The environmental tests on Antenna Tile STM level (see details on verification approach) are planned for end of the year.
The paper deals with the details of the Sentinel-1 SAR antenna thermal design, its accommodation and thermal interaction with the S/C bus. Special attention will be paid to the verification approach for the large antenna.