Scattering and Coupling Properties of a Slotted Elliptic Cylinder

Near-field analysis and coupling of a perfectly conducting slotted elliptic cylinder excited by an electric line source placed inside or outside the cylinder is considered. The solution can be easily extended to account for a z-polarized incident plane wave excitation. The separation of variables technique is used to express external and internal fields in terms of Mathieu and modified Mathieu functions with unknown expansion coefficients. The problem is then reduced to an integral equation in terms of the aperture field. The solution of the integral equation is carried out by expressing the aperture field in terms of a Fourier series expansion with unknown coefficients. Then Galerkin’s technique is introduced to solve for the unknown aperture field coefficients. Results for the penetrated and near fields are given in terms of different parameters such as location and type of the excitation, aperture width, cylindrical axial ratio, and the loading of the cylinder.