Principal Investigator: Todd Gaier, NASA Jet Propulsion Laboratory

Proposal Title: Millimeter-Wave MMIC Atmospheric Temperature and Humidity Sensors

The Millimeter-Wave MMIC Atmospheric Temperature and Humidity Sensors 36 month program will develop compact (<0.5kg), low power (<0.4W), multi-use, low-cost, calibrated radiometers operating in the 100-140 and 170-210 GHz frequency range. These radiometers will utilize InP and GaAs transistor monolithic integrated circuits (MMICs) which have enabled a factor of 100 reduction in volume as compared to the sensors presently used in programs such as AMSU and MLS. The primary science application of these sensors is the measurement of atmospheric temperature and pressure through the 118 GHz oxygen line and humidity through the 183 GHz water vapor line. These quantities are of fundamental interest to atmospheric studies and the water vapor sensing has become increasingly important to earth remote sensing experiments which require correction for the variations of atmospheric path delay such as Topex/Poseidon. The radiometers are stand-alone instruments which can be inserted into a variety optical systems for specific science applications.

One specific application of these sensors is for an Array Microwave Atmospheric Limb Sounder (AMLS) which has been proposed to the New Millennium program and is further recommended by a J. Waters reply to the recent NASA Request for Information for Science and Application Missions in the Post-2002 Era. The effort will develop and perform a laboratory demonstration of AMLS receiver modules so that they would be ready for a "fast track" response for a flight demonstration.