Reconstruction of the Height Profiles of the Electron Concentration Based on Vertical Sounding Data with the IRI Model

A technique is proposed for the determination of the height profiles of the electron plasma frequency from measurements of the virtual heights during vertical sounding of the ionosphere. Additional information on the height course of the electron concentration from IRI-2016 model data in regions invisible to an ionosonde was used to solve this problem. The proposed algorithms for the correction of height IRI distributions for night- and daytime ionograms, including those with the screening sporadic layer Es, allow solutions that best fit the experimental values of the virtual heights. In the daytime conditions, an IRI profile corrected to the virtual heights in the E region satisfactorily estimates the radio-wave absorption in the D and E regions, and the profile is in good agreement with rocket measurements. The introduction of key parameters into the IRI model (maximal heights and critical frequencies of the layers and parameters B0 and B1, which determine the shape of the profile calculated for the F region) makes it possible to retrieve an IRI profile corrected for real conditions. Analysis of the virtual heights calculated with this profile shows that they significantly differ from the experimental values in the lower F region, which can result in errors in the calculation of the length of the radio path. In addition, difference of profiles in the D and E regions can result in large errors in the absorption of the radio waves reflecting above these regions.