DIAGNOSTICS OF LARGE-SCALE STRUCTURES OF THE HIGH-LATITUDE IONOSPHERE BASED ON TOMOGRAPHIC TREATMENT OF NAVIGATION SATELLITE SIGNALS AND OF DATA FROM IONOSPHERIC STATIONS

In this paper it is shown that. by using methods of ionospheric tomography when analyzing navigation-satellite signals at spatially separated reception sites, it is possible to expand the possibilities of diagnosing and monitoring large-scale structures of the high-latitude ionosphere such as the main ionospheric trough. The best space- and time-resolution is achieved in the case of a combined treatment of data from standard ionospheric stations and from satellite signal reception sites. The analysis has been made using modelling methods on the basis of experimental data from a meridional chain of ionospheric stations located in the latitude range 56-70-degrees-N.