Wave-matching analysis of an open-ended circular waveguide with an infinite conducting flange

Abstract

This paper presents a full-wave analysis of radiation associated with an antenna located inside a conducting waveguide. The opening of such a waveguide is flush-mounted on an infinitely extended ground plane and covered by a hemi-spherical dielectric shell. The electromagnetic fields radiated by an antenna located inside the waveguide and the dyadic Green's functions in such a structure are formulated using the wave-matching technique. The scattering coefficients of the dyadic Green's functions, coupled to each other and expressed in matrix form, are derived by matching the boundary conditions on circular waveguide conducting walls and the dielectric interfaces. As an application, the radiation patterns of the open aperture excited by a dipole antenna located inside the circular waveguide are obtained for various dimensions of the radiating system.