Integrated Water Vapor Estimation Through Microwave Propagation Measurements: First Experiment on a Ground-to-Ground Radio Link

Year: 2021

Authors: Montomoli F., Macelloni G., Facheris L., Cuccoli F., Del Bianco S., Gai M., Cortesi U., Di Natale G.; Toccafondi A., Puggelli F., Antonini A.,; Volpi L., Dei D., Grandi P., Mariottini F., Cucini A.

Autors Affiliation: Institute of Applied Physics ´Nello Carrara,´ National Research Council (IFAC-CNR), 50019 Sesto Fiorentino, Italy; Department of Information Engineering, University of Florence, 50139 Florence, Italy; National Institute of Optics, National Research Council (INO-CNR), 50019 Sesto Fiorentino, Italy; Department of Information Engineering, University of Siena, 53100 Siena, Italy; Laboratory of Monitoring and Environmental Modelling for the Sustainable Development (LAMMA), 50019 Sesto Fiorentino, Italy; Pasquali Microwave Systems, 50142 Florence, Italy; Florence Engineering s.r.l., 50141 Florence, Italy; Laboratori Victoria s.r.l., 51100 Pistoia, Italy; Wavecomm s.r.l, Z.I. Belvedere, 53034 Colle di Val d´Elsa, Italy.

Abstract: Measurement of water vapor (WV) in the lower troposphere on a continuous temporal basis would improve our knowledge of the atmospheric dynamics and the performance of numerical weather prediction models. In recent studies, a new measurement concept, the normalized differential spectral attenuation (NDSA) approach, was proposed. It is based on measurements of differential attenuation at 18.8 and 19.2 GHz performed along a tropospheric radio link. While NDSA measurement at a fixed elevation angle provides information on integrated WV (IWV), measurements at different elevation angles allow to retrieve the vertical WV content profile. A prototype NDSA demonstrator, which consists of two units, a synthesized transmitter and a software-defined radio receiver, has been designed and implemented. The system was accurately characterized through several laboratory tests, and then a first experimental campaign was conducted at fixed elevation angle along a ground-to-ground radio link. Obtained results confirm the sensitivity of the NDSA measurements to the IWV along such link with a good agreement with the existing ground-based and satellite data products.


More Information: This work was supported by the SWAMM Project (PAR FAS 2007-2013), ASI Project SATCROSS (ASI contract N. 2020-2-U.0).
KeyWords: Microwaves, normalized differential spectral attenuation (NDSA), radio link, scintillation, water vapor (WV)
DOI: 10.1109/TGRS.2021.3067929