Radiation from a Plasma Layer with a Strong Longitudinal Irregularity

Abstract

The efficiency of conversion of the energy of a surface wave into radiation at longitudinal irregularities of a planar plasma layer is studied. The analysis is performed by the spectral expansion of the field in a complete set of surface and pseudosurface waves. The system of integro-differential equations for the coefficients of expansion that determine the amplitudes of the transmitted, reflected, and scattered waves as well as the radiation pattern is solved in the case of a rapid change in the plasma density. The coefficients of transformation of energy into the energy of radiation as functions of the gradient of the plasma density for different values of the electrical length of the region of plasma irregularity and the electric thickness of the plasma layer are found. Examples are demonstrated when the fraction of the energy of the surface wave transformed into radiation reaches 60–70%. Radiation patterns that proved to be highly directional and having one lobe with the maximum at an angle of a few degrees to the direction of propagation of the surface wave are calculated.