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Sentinel-1 in-orbit calibration plan

The ESA Sentinels constitute the first series of operational satellites responding to the Earth Observation needs of the EU-ESA Global Monitoring for Environment and Security (GMES) programme. The GMES space component relies on existing and planned space assets as well as on new complementary developments by ESA. In contrast to SAR systems already existing in C-band like ASAR/ENVISAT or RADARSAT-2, high demands on the radiometric stability and accuracy are made for Sentinel-1. The mission depends on the method of calibrating the entire Sentinel-1 system in an efficient way. This paper describes the strategy and provides a plan of all activities required for in-flight calibration of Sentinel-1.