MIRAS Functional Test Results for the SMOS Mission

MIRAS (Microwave Imaging Radiometer with Aperture Synthesis) is the single payload on board ESA's Soil Moisture and Ocean Salinity (SMOS) second Earth Explorer Opportunity Mission. Although MIRAS is a complex 69 element L-band interferometer with full on-board calibration capability, end-to-end performance tests have been possible on a reduced but yet representative part of the instrument, built to engineering model (EM) space standards. This paper presents the most relevant results obtained during the testing of the EM model of MIRAS including explanations for any deviations from expectations, and from them, the best estimation of the achievable performance by the SMOS mission. This is the first measurement campaign of MIRAS, which shall be followed in the future by further verification tests of the full flight model when this be completed