HIGH SENSITIVITY ACTIVE CAVITY RADIOMETER (HS/ACR)

ACTIVE CAVITY RADIOMETER (ACR) SENSORS HAVE DEMONSTRATED THEIR STATE-OF-THE-ART ACCURACY AND PRECISION FOR SOLAR OBSERVATIONS IN SPACE FLIGHT APPLICATIONS AS THE SENSORS OF THE ACTIVE CAVITY RADIOMETER IRRADIANCE MONITOR EXPERIMENT ON THE SOLAR MAXIMUM MISSION. THE DESIGN AND OPERATIONAL ADVANTAGES OF THE SOLAR ACR SENSORS HAVE BEEN SUCCESSFULLY APPLIED TO WIDE AND MEDIUM FIELD OF VIEW EARTH-VIEWING SENSORS ON THE ERBS AND ERBE EARTH RADIATION BUDGET EXPERIMENTS. THE SAME SENSOR ADVANTAGES COULD BE APPLIED TOTHE NARROW FIELD OF VIEW EARTH-VIEWING OBSERVATIONS OF FUTURE ERB-TYPE EXPERIMENTS, REPLACING THE INACCURATE AND UNRELIABLE SCANNING SYSTEMS IN CURRENT USE, IF THE SENSITIVITY OF THE SOLAR ACR SENSORS WERE INCREASED BY BETWEEN ONE AND TWO ORDERS OF MAGNITUDE. THE PROPOSAL OBJECTIVE IS TO SUITABLY MODIFY THE ACR SOLAR SENSOR CAVITY DESIGN AND ELECTRONICS TO ACHIEVE SUCH AN IMPROVEMENT IN PERFORMANCE, WITHOUT SACRIFICING ACCURACY.