EOS Microwave Limb Sounder GHz optics design and eld-of-vie w calibration

o This paper describes the optics design and eld-of- view calibration for the GHz module of the Microwave Limb Sounder instrument on NASA's Aura satellite. Details of near eld pattern measurements are presented. Estimated systematic scaling uncertainties (3 ) on calibrated limb radiances, due to FOV calibration uncertainties, are below 0.4%. 3 uncertainties in beamwidth and relative pointing of channels within the GHz module are 0.006 and 0.003 , respectively. The uncertainty in forward model radiances, due to scan dependence of FOV patterns, is less than 0:24 K. Renements to the calibration using in-ight data are discussed.

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