Ionospheric TEC estimations using dual frequency coherent L1/L5 signals from the geostationary SBAS satellites

In this work we study coherent L1/L5 signals of satellite based augmentation systems (SBAS) geostationary satellites observed with geodetic GNSS receivers located at equatorial and mid-latitudes and estimate corresponding geostationary total electron content (TEC) and errors of such estimations. We also provide the comparison of geostationary TEC with the data of nearest ionosondes, as well as wavelet analysis of geostationary TEC, providing typical periods of observed variations at different time scales and discuss the capabilities of SBAS TEC observations in connection with ionospheric effects of solar flares.