Research on the Characteristics of Focusing Effect of Electromagnetic Wave in Inhomogeneous Plasma

The focusing effect of electromagnetic wave in inhomogeneous plasma is investigated in both theory and simulation. In this paper, the nonuniform plasma refers to a plasma column whose density increases gradually parabolically in the radial direction while remaining constant in the axial direction. By using Maxwell’s equations and the dispersion relation of electromagnetic wave propagation in plasma, the analytical expression of the full width at half maximum of electromagnetic waves is obtained. The evolution of electromagnetic wave energy reflects the influence of electromagnetic wave frequency and plasma inhomogeneity on the focusing effect. This research provides potential applications in reducing electromagnetic wave energy dissipation and improving energy transmission efficiency. Furthermore, it provides a methodology for the ionosphere and space communications, expanding the field of research on the interaction of plasma and electromagnetic waves.