IRI slant electron content predictions Original Research Article

The International Reference Ionosphere model is used to calculate the slant electron content (SEC) encountered by a radio signal emitted from a satellite and received at a middle latitude station. Two cases were considered, namely: a) The satellite and the ground station are in the same meridian; b) the satellite and ground station have different longitudes. For the first case only modelled values for different solar activities, hours and seasons are considered. For the second case a comparison with measurements obtained with a synchronous satellite radio signal during a low solar activity period is done. The results show the solar control and the dependence with the zenithal angle of the satellite. The comparison with measurements shows very good agreement between predictions and measurements for some periods. But, in general, the model underestimates SEC. These results suggest that additional studies covering more stations and conditions are required in order to confirm the need of improvements in IRI model