| Radiation by conformal antennas, flush-mounted to surfaces with varying curvature, is of considerable importance to design engineers. Applications of such antennas are found in the aerospace, automobile, and watercraft industries. Conformal antennas are important in these areas due to their relatively low cost, low profile, and consumer appeal. However, accurate and flexible design methods for such antennas have not been offered in the literature to date.; In this research, the highly versatile finite element method is combined in a hybrid formulation with a boundary integral mesh closure scheme to accurately model the fields within, and in the aperture of, a cavity-backed antenna flush-mounted in a perfectly conducting infinite elliptic cylinder. For the sake of efficiency, an asymptotically valid dyadic Green's function based on the Uniform Theory of Diffraction (UTD) for surface fields due to a source on a smooth perfectly conducting surface with arbitrary curvature is used in the boundary integral. This development represents a significant advancement over prior techniques since surface curvature variation, either across a single element or across an array of elements, is now accurately included into the antenna model. An advantage of this approach is the ability to model cavities with curvature varying from planar to the constant curvature of a circular cylinder. Eigenmodes will be given for planar-rectangular, circular-rectangular, and elliptic-rectangular cavities recessed in the cylinder. Furthermore, the input impedance of a conformal cavity-backed patch antenna will be given. Also, The mutual coupling between microstrip antennas mounted in a ground plane, a circular and an elliptic cylinder is investigated in this research. |
