Furthermore atmosphere and ground surface measurements will be performed for validating the instrument 
operation in field conditions. 
Acknowledgements. This study is part of a project of development of infrared radiometers suitable for 
field measurements, which involves the following laboratories: CRG/CNRS (Garchy), ENSPS/GSTS 
(Strasbourg), INRA (Avignon) and LOA (Lille). Financial support is provided by the Agence Française de 
l'Espace (support to research decision № 93/CNES/0373). We gratefully thank G. Guyot who efficiently 
coordinated the various teams. Thanks are extended to J. Legrand, F. Herlemont (LSH, Lille) and B. Sombret 
(LAS1R, Lille) for their help in the studies of the instrument detector and optical components, to X. Gu (INRA, 
Avignon) for his preliminary study, and to L. Ménenger (LMD, Palaiseau) for his advices about the infrared 
measurements. 
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