Radiation characteristics of a slotted cylindrical antenna surrounded by a moving magnetoplasma layer

Radiation from an aperture in a conducting cylinder surrounded by a magnetoplasma layer moving in the axial direction is treated theoretically. Numerical computations are carried out for axial and circumferential slot apertures. For the axial slot case, it is shown that in addition to the main-polarized fields, cross-polarized fields occur in the presence of motion of the plasma layer, and that the radiated power pattern of each polarized field depends on both the constitutive and the velocity parameters of the plasma. For the circumferential slot case, the radiation patterns for two polarized fields are obtained separately, and numerical results are presented. It is shown that the radiated power intensity decreases suddenly at the upper hybrid resonance, which depends upon the velocity and the constitutive parameters of the plasma due to the Doppler effect. In the vicinity of the resonance, rapid oscillations appear in the pattern, and hence the radiated power pattern is remarkably distorted in the resonance region.