Phase error assessment of MIRAS/SMOS by means of the redundant space calibration

SMOS is the acronym for the Soil Moisture and Ocean Salinity mission by the European Space Agency (ESA) [1]. Its single payload, the Mcrowave Imaging Radiometer using Aperture Synthesis (MΓRAS), was successfully launched in November 2009. A six months Commissioning Phase was devoted to bring the satellite into a fully operational condition and to characterize the payload using specific orbits to check all instrument modes [2]. An on- going activity is devoted to analyze the contribution of each single calibration procedure to the overall radiometric accuracy in order to assess the dominant sources of spatial errors. In this framework, this paper is devoted to assess the performance of the phase calibration procedures by means of the so called Redundant Space Calibration (RSC)¹.