Two-dimensional microwave scattering by fluctuations of plasma density and magnetic field

A system of 2D full wave equations is solved for the case of microwave scattering by plasma density and magnetic field fluctuations near the cut-off layer. The 2D field structure in ordinary-to-ordinary scattering (O to O), extraordinary-to-extraordinary scattering (X to X) and O to X, X to O mode conversion processes is studied as well as the influence of refraction, side scattering, diffraction on both X- and O-mode reflection near the cut-off layer. For the case of relatively large antenna size the expressions obtained reveal high sensitivity of the scattered field to the plasma disturbance wavenumber in the transverse direction. For the horn size of 1-2 wavelengths the sensitivity is weak. Numerical examples exhibit multisource spatial distribution of the scattered field. Resonance features of modes scattered by wave-shaped fluctuations were found to be similar to the 1D case.

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