ESTIMATION OF CRITICAL FREQUENCY AND HEIGHT MAXIMUM FOR PATH' MIDDLE POINT ON EVIDENCE DERIVED FROM EXPERIMENTAL OBLIQUE SOUNDING DATA. COMPARISON OF CALCULATED VALUES WITH EXPERIMENTAL AND IRI VALUES

摘要

The work is devoted to experimental checking of technique for estimation of f_0F2 and hmF2 values in path' midpoint through oblique sounding (OS) data. In this work data obtained by Irkutsk chirp-sounder on the Norilsk-Irkutsk path were used and data obtained by Podkamennaya Tunguska ionospheric station (which located near estimating path' middle point) were used also. During the calculation, the experimental distance-frequency characteristics (DFC) of path are recalculated into height-frequency characteristics (HFC) in path' midpoint by means of Smith method. It lets us to determine f_0F2 value in path' middle point. For hmF2 definition N(h) profile is used which was obtained by recalculation of HFC by means the Guliaeva technique. Also the fast method of recalculation was probed in two DFC points. In the work comparison was made between calculated f_0F2 values and experimental f_0F2 values obtained by Podkamennaya Tunguska ionospheric station. Comparison of estimating hmF2 values with values calculated by Dudeney method from experimental f_0E, f_0F2, M(3000)F2 values at Podkamennaya Tunguska was carried out. In addition, estimating values was compared with values given by the IRI model. A capability of the IRI model adaptation by f_0F2 and hmF2 values was investigated. It will help during diagnostics, working out regional models of ionosphere and during the adaptation of various models of ionosphere to the real conditions.