TM scattering from a dielectric-loaded semi-circular trough in a conducting plane

Abstract

The behavior of TM-wave scattering from a dielectric-loaded semicircular trough in a conducting half-space is investigated. The dielectrics loading are made of upper and lower half-circular cylinders which lie in a semi-circular trough in the perfectly conducting plane. The formulation is numerically evaluated to investigate the scattered field pattern for various dielectric loading conditions. It is found that the scattering patterns exhibit the resonant behavior due to both of the concave surface contour and the dielectric loading. The field magnitude inside the trough is found to be much greater than the outside, thus indicating that the trough focuses the incident beam inside the trough. And the trough size corresponding to the minima and maxima of the electric field magnitude are found to be determined by the cutoff frequencies of the TM circular waveguide modes.