Estimation of gaseous absorption using surface and radiosonde meteorological measurements

For radiowave propagation on Earth-space communication links at high frequencies such as Ka-band, the effect of atmospheric gaseous absorption mainly due to oxygen and water vapor is the primary cause of attenuation. This paper examines the applicability of the surface based Crane's model currently employed by the Advanced Communications Technology Satellite (ACTS) propagation experiment for estimation of attenuation due to atmospheric gaseous absorption (AGA), developed for Oklahoma, to sub-tropical climate regions such as Florida. The millimeter-wave propagation model (MPM) is used as a basis of comparison since it uses the direct atmospheric measurements (temperature, relative humidity, and pressure) made at different levels of the atmosphere with radiosonde instrumentation. The AGA was individually examined for oxygen and water vapor. Finally, accuracy of the Crane's model was verified by computing the attenuation results using real acquired data for both models and comparing their results. A MATLAB based graphical user interface (GUI) was developed and utilized to provide a user friendly environment for visualization purposes and ease of data analysis.