SMALLSAT SAR: AN AFFORDABLE, ALL-WEATHER IMAGING SOLUTION FOR DEVELOPING COUNTRIES

摘要

Small, affordable spacecraft have in the last several years begun to deliver regular, medium and high resolution Earth imagery in several wavebands on a commercial basis to a wide user community. Successes include the SSTL's Disaster Monitoring Constellation delivering LandSat and SPOT compatible visible and near-IR data for a per mission cost of < $20M, the European PROBA small satellite with its CHRIS hyperspectral camera, recently celebrating 6 years in orbit. This paper will outline SSTL's experience trying to market, develop and launch a real low cost radar mission. The paper will describe requirements for a synthetic aperture radar or SAR instrument engineered to suit the constraints of volume, power and mass available on a small spacecraft, typically less than 350kg launch mass and constrained to a mission cost below $50M (excluding launch & insurance). SSTL is seeking partners to develop a new, miniature SAR ideally suited to launch on small satellites, by low cost launchers and in constellations for a range of users. Disaster response and climate change impact monitoring are key applications for such a mission. The paper will describe the overall mission design, and requirements for spacecraft, ground segment with mission and spacecraft control, and payload data processing facility which are being developed. A summary of requirements for a realistic low cost SAR payload will be presented, intended for issue in 2007 as a Request For Information to potential payload providers. The mission concept targets a first launch by the end of the decade, this will further revolutionise the rapidly growing field of low cost, small satellite missions.