Long distance propagation of HF radio waves

The present work deals with a systematic description of the theory of radio wave propagation in a three-dimensional inhomogeneous ionosphere. Consideration of the features of the actual horizontally-inhomogeneous ionosphere makes it possible to significantly simplify the problems of radio propagation and to derive the main relations of the adiabatic approximation theory. The spherically-symmetric ionosphere is considered along with the horizontally-inhomogeneous ionosphere, regularities of very long-distance radio wave propagation in the ionosphere, the calculation of long-distance radio paths, radio wave scattering, nonlinear phenomena, radio wave propagation in the magnetosphere, the radio wave field distribution in connected waveguide ducts, analytical models of ionospheric parameters, and the wave theory of HF radio wave propagation in a horizontally-inhomogeneous ionosphere. Attention is given to very long-distance and magnetospheric propagation, long-distance oblique sounding, and signal fluctuations in the reception point.