Millimeterwave Reflectivity Tests On Metop-Sg Mwi On Board Calibration Target

The On-Board Calibration Target (OBCT) for the Micro-Wave Imager instrument on the MetOp-SG-B satellite is a microwave blackbody, operating between 14 and 220 GHz (extended frequency range), providing the MWI receivers with a warm calibration reference. It is designed for an emissivity better than 0,9999 over the MWI 26 channels (including dual polarization channels). TheOBCTradiometric performance has been extensively verified in ISTP (formerly IFP) microwave laboratory, by measuring reflectivity over the extended bandwidth. Measurement techniques and results are described in this paper, showing that the OBCT models tested so far are fully compliant with the MWI requirements.