Results of a New Campaign for Ground-to-Ground Measurements of Water Vapor through the Normalized Differential Spectral Attenuation (NDSA) Technique

The NDSA technique, proposed for estimating the IWV (Integrated Water Vapor) through a tropospheric radio link, operates by transmitting two sinusoidal signals at K band and gauging their reception power. This enables the estimation of IWV based on the different signals’attenuation. In 2018, an instrument prototype was finalized for the first measurement campaign, showcasing the NDSA method. In this paper we describe the improved version of the instrument, used for a second campaign in 2022, the procedures for its characterization and generation of data, and some of the campaign outcomes.