Abstract-Electromagnetic waves scattering in turbulent anisotropic collision magnetized ionospheric plasma is investigated using complex geometrical optics approximation.Correlation function of the phase fluctuations of scattered radiation is obtained taking into account both electron density and magnetic fields fluctuations. The features of the angular power spectrum of scattered radiation are investigated analytically and numerically. The expressions of broadening of the spatial spectrum have been obtained for both powerlaw and anisotropic Gaussian correlation functions of electron density fluctuations. Gaussian spectral function takes into account the axial ratio of the field-aligned irregularities and the angle of inclination of prolate irregularities with respect to the external magnetic field. The variance of the phase and scintillation level of scattered radiation are calculated numerically for F -region irregularities of the ionosphere. The conditions of non-fully and fully developed diffraction patterns have been determined.

Abstract.A complete theory of low-frequency MHD oscillations of the Earth's weakly ionized ionosphere is formulated. Peculiarities of excitation and propagation of electromagnetic acoustic-gravity, MHD and planetary waves are considered in the Earth's ionosphere. The general dispersion equation is derived for the magneto-acoustic, magnetogravity and electromagnetic planetary waves in the ionospheric E-and F-regions. The action of the geomagnetic field on the propagation of acoustic-gravity waves is elucidated. The nature of the existence of the comparatively new largescale electromagnetic planetary branches is emphasized.

Second order statistical moments of the phase fluctuations are obtained taking into account the boundary condition, diffraction effects and polarization coefficients of the ordinary and extraordinary waves. The variance and the correlation function are calculated for arbitrary 3D spectral function of electron density fluctuations containing both anisotropic Gaussian and power-law spectra; anisotropy coefficient and the orientation angle of elongated plasma irregularities. The phase scintillation index and the scintillation level are analyzed numerically. Maximum of the scintillation index for small-scale irregularities is in the interval 0.2-0.3 corresponding to the moderate scintillation intensity, within the weak-scatter regime. Splashes are revealed for different anisotropy factor of elongated largescale irregularities varying orientation angle with respect to the lines of force of geomagnetic field. Scintillation index is calculated for small-scale irregularities using the "frozenin" assumption and taking into account movement of rigid irregularities. Log-log plots of the power spectrum of the intensity fluctuations have the same minimums satisfying the "standard relationship" of scattered ordinary and extraordinary waves. It was shown that the normalized scintillation level growth in both non-fully-developed diffraction pattern and in transition zone increasing anisotropy factor. Rising orientation angle scintillation level decreases and splashes arises in fully developed scintillation region.

Differential equation for two-dimensional spectral function of the phase fluctuation is derived using the modify smooth perturbation method. Second order statistical moments of the phase fluctuations are calculated taking into account polarization coefficients of both ordinary and extraordinary waves in the turbulent collision magnetized plasma and the diffraction effects. Analytical and numerical investigations in the ionospheric F region are based on the anisotropic Gaussian and power law spectral functions of electron density fluctuations including both the field-aligned anisotropy and field-perpendicular anisotropy of the plasma irregularities. Scintillation effects in this region are investigated for the small-scale ionospheric irregularities. The large-scale background plasma structures are responsible for the double-humped shape in the spatial power spectrum taking into account diffraction effects. Numerical calculations are based on the experimental data of the navigation satellites.Â

No abstract

No abstract

No abstract

The features of coherent GreenÏs function in a nondispersive medium with spatial-temporal dielectric permittivity Ñuctuations are considered in this paper. General analytical expression for the mean Green Function is obtained at arbitrary covariance function. Numerical simulations were carried out too.