Peculiarities of the inverse problems of vertical radio sounding of the ionosphere

Abstract

At the interpretation of ionograms (obtained by ground-based or satellite soundings) in terms of electron density, or at that of absorption measurements in terms of an effective electron collision frequency or at that of Doppler measurements in terms of plasma motions, problems arise which might be seen as comparable in character. One can, in fact, resolve these problems by inversion of the first-kind Volterra and Fredholm integral equations. The fact that the first-kind Fredholm equations belong to the class of ambiguous problems necessitates the use of additional information and data which were measured with great precision. Therefore, the main problems in groundbased and satellite diagnostics of the ionosphere is an improvement of the precision in measuring parameters of radio signals and the development of controlling algorithms for the solution of inverse problems.