K.V. Raubo, V.E. Zakharov

Analysis is done to investigate how the complex geometric optics may be employed to investigate the propagation of HF waves in the ionosphere. As shown. weak non-uniformity of ionospheric plasma may be violated while waves propagate in the ionosphere. The violation is caused by an increase of the gradient values of the electron density.

To describe the propagation of waves in plasma, the system of characteristic equations is evolved. To do this, the complex values of the momentum vector are considered.

The numerical experiments are performed to investigate the formation of both the ray trajectories and absorption of the wave energy in the ionospheric plasma. The ionospheric plasma is considered to be non-uniform and anisotropic medium for propagation of HF waves. The behavior of both ionospheric plasma and gas of neutral atmosphere depends on geophysical conditions. To take this dependence into account, the empirical models for both ionosphere and neutral atmosphere are used. The plasma of ionosphere is anisotropic due to the influence of geomagnetic field.

The results of numerical experiments may be used to predict the conditions for propagation of HF waves in dependence on geophysical conditions.

Raubo K.V., Zakharov V.E. Investigation of the short-wave propagation in the ionospheric plasma under the violation of conditions of
the weak non-uniformity of medium. Radiotekhnika. 2023. V. 87. № 2. P. 5−10. DOI: https://doi.org/10.18127/j00338486-202302-01 (In Russian)

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