E.B. Ipatov, E.A. Palkin, V.I. Chivilev, D.E. Ipatov
The possibility of complex structure of the unperturbed ionosphere modeling based on a fairly simple model is investigated. Correction is carried out for the coefficients of the model of the electron density on the base of the experimental data obtained from vertical sounding ionograms. The comparison is performed for the range of possible changes of the total electron content of the ionosphere for the quiet Sun and the values of this quantity, registered GPS stations, the day before the earthquake. The numerical simulation of the Doppler shift frequency and group delay signal in the ionosphere of the Earth, based on the method of bi-characteristics is performed. The «sensitivity» of the Doppler parameters of the model to changes in the ionosphere is estimated. A simple method of monitoring large-scale ionospheric disturbances in the ionosphere is suggested.