Micro-wave imager radiometer antennas configurations

MWI (Micro Wave Imager) is a multi-channel microwave radiometer which will be embarked on the next MetOp-SG (MetOp Second Generation) mission aimed to provide cloud and precipitation observations as well as water vapour and temperature gross profiles. MetOp-SG includes two series of three satellites, embarking a total of 10 different instruments. The satellites are procured by the European Space Agency and developed by Airbus Defence and Space. The present paper provides a general description of the MWI antenna design and its performance. As it is well known, the antenna system has an important role for both the radiometric accuracy and the spatial resolution of the instrument, since it has to guarantee at the same time very good beam efficiency and high spatial resolution. The antenna is able to operate over the frequency range between 18 GHz and 200 GHz, split in eight main frequency bands, each one receiving up to 5 channels as defined by the user requirements.