Hybrid finite-boundary element analysis of microwave antennas for high power applications

Summary form only given. A hybrid finite-element-boundary-element method (HEM) has been developed to provide an effective tool for the design and analysis of high-power microwave antennas. Finite elements are used to represent the interior region which has sources and structures. and boundary elements are used to represent the boundary and can be used to evaluate the far field. For implementation of the hybrid program, the Galerkin weighted residual method is employed using second-order triangular elements, and the boundary integral equation is evaluated using the point matching method. The hybrid method was applied to a parallel-plate waveguide to analyze the near-field pattern as well as the far field. The method was applied to Vlasov-type radiators and to various antenna systems with reflectors. The results of the method are in good agreement with the exact solution and with the geometrical theory of diffraction. Absorbing boundary conditions (ABCs) have been combined with the finite-element method as an alternative to the boundary integral equation in the HEM. The use of ABCs reduces both computing memory and time requirements