AFRL-AFOSR-UK-TR-2016-0012 HiRadProp - High-frequency modeling and prediction of troposheric radiopropagation parameters from ground-based multi-channel radiometric measurements between Ka and W band

Sun-tracking microwave radiometry is a ground-based technique where the Sun is used as abeacon source. The atmospheric antenna noise temperature is measured by alternately pointingtoward-the-Sun and off-the-Sun according to a beam switching strategy. By properly developing an adhoc processing algorithm, we can estimate the atmospheric path attenuation in all-weather conditions.A theoretical framework is proposed to describe the Sun-tracking radiometric measurements and toevaluate the overall error budget. Two different techniques, based respectively on elevation-scanningLangley method and on surface meteorological data method, are proposed and compared to estimatethe clear-air reference. Application to available Sun-tracking radiometric measurements at Ka, V andW band in Rome (NY, USA) is shown and discussed together with the test of new physically-basedprediction models for all-weather path attenuation estimation at Ka, V and W band from multichannelmicrowave radiometric data. Results show an appealing potential of this overall approach inorder to overcome the difficulties to perform satellite-to-Earth radiopropagation experiments in theunexplored millimeter-wave and submillimeter-wave frequency region Distribution Statement This is block 12 on the SF298 form. Distribution A Approved for Public Release Explanation for Distribution Statement If this is not approved for public release, please provide a short explanation. E.g., contains proprietary information.