Abstract
In this paper, we present an ionospheric estimation method based on GNSS Regression models (abbreviated by GR models) and show to derive the ionospheric delay (or advance) local model in the sky over Japan using the Gps Earth Observation NETwork (GEONET) data provided from the Geographical Survey Institute (GSI) of Japan. By showing the GR models for GNSS observables in the case of known positions (in the reference stations), we derive a method to estimate the ionospheric delays (or advances) as well as the so-called integer ambiguities contained in L1 and L2 band carrier-phase data at the reference stations. Then we emphasize the importance to estimate integer ambiguities of their own receivers at the reference stations.
