Space constellation of high-resolution SARs for fast global access

This paper reports a system study of a constellation of spaceborne advanced Synthetic Aperture Radars (SARs) for high temporal, geometric and radiometric resolution mapping of the Earth surface. The study is aimed at the identification of overall performance and feasibility of an integrated remote sensing system to be deployed within the next fifteen years for nearly real-time high accuracy mapping, with special emphasis on natural disasters management. The SAR conceptual design includes the frequency identification and the quantitative evaluation of the main system parameters. Thanks to the capability of range beam steering, it is demonstrated that fast global access of whatsoever area on the Earth surface can be obtained by means of two sets of identical satellites, adequately located along sun-synchronous orbits. Finally, the spacecraft pointing knowledge requirements are pointed out, taking global fast access and target localization into account.