Radiation From a Corrugated Circular Waveguide With a Flange

Abstract

_—Electromagnetic radiation from a corrugated waveguide with a flange is considered with the eigenvector expansion approach. The continuous and discrete eigenvectors are used to match the boundary conditions and a system of simultaneous equations for the discrete modal coefficients is formulated. A rigorous solution is presented in convergent series and its behavior is illustrated in terms of radiation pattern, beam axial symmetry, and return loss. The corrugation cut on the inner wall is found to focus an input beam into the central region of the waveguide, yielding desirable characteristics such as axial beam symmetry, low sidelobe level, and low cross-polarization level.