Scattering from a cylindrical waveguide with rectangular corrugations

Electromagnetic scattering from a circular cylindrical waveguide with recta ngular corrugations is considered in this paper. An analysis method based o n dyadic Green's functions and Fourier transforms is used to get the field in terms of modal currents induced on the corrugation openings. The fields are expressed through a series of modal eigenfunctions in the corrugations, and are integrated to get the unknown expansion coefficients. This analysi s method can easily be extended to find the dispersion relations of the cor rugated waveguide. The series solution obtained is analytic and suitable fo r numerical computation. Numerical results are presented to illustrate the scattering behavior of a corrugated cylindrical waveguide in terms of frequ ency and waveguide geometry.