Application of high-order edge elements and PML to horn antenna analysis.

摘要

There are many methods for truncating finite element (FE) meshes for unbounded problems. Among them the Perfectly Matched Layer (PML) is the most promising. In this thesis, application of the PML to a high-order FE method is investigated, particularly with respect to its ability to analyze horn antennas.; The anisotropic material properties of the PML can be chosen such that a plane-wave incident from free space onto the anisotropic material will have no reflection. The interface of the absorber is made reflectionless by choosing the appropriate &egr; and mu values to be complex diagonal tensors. The performance parameters of this absorber are explored.; For the finite element analysis, high-order hierarchal edge elements are used, and how the element size and order of the basis function affect the solution accuracy and computational cost are observed. It is possible to achieve very good absorption for comparatively less computational cost by using relatively thin absorbing layers along with careful consideration of the relations of the element size and the order of the basis function. The impedance characteristics and far field radiation pattern of a horn antenna are computed and compared with previously-published measured results.