The technique of calculation of electron density profile from initial distribution using vertical sounding ionograms

The technique of vertical sounding ionogram processing is presented. Our approach is based on modifying initial electron density profile. Initial profile can be obtained from IRI model prediction or from the previous sounding of ionosphere. The method of profile fitting to the ionogram does not require echo traces extraction. The results of practical application of the technique are presented. Technique is applied to processing of nighttime ionograms, as well as to processing of an “apparent F1 layer” phenomenon.