Design and development of IASI instrument

The purpose of this paper is to present the IASI overall architecture and the IASI functional chain including optics and interferometer, analogue to digital acquisition, on board and on ground digital processing. It points out special features of IASI's design and critical technologies. The IASI technical description is followed by a development status including activities on breadboards, engineering models, proto flight and flight models with emphasis put on achieved critical steps. A companion paper by CNES will provide detailed information on the IASI mission and instrument key performance achievement.