Point-based high-order moment method for thin wire scattering and antenna analysis

Abstract

Electromagnetic scattering method of moment (MoM) solutions typically employ low-order basis and testing functions. That is functions that lead to fixed error convergence rates. In contrast to a low-order scheme, a high-order method should lead to controllable error convergence. Further, a high-order scheme should reduce the solution error with a modest increase in computational resources and complexity. A number of high-order basis functions have been introduced for MoM solutions employing such basis can result in high-order accuracy using a Galerkin solution. The difficulty is that a Galerkin scheme results in an expensive double integration that must be computed to controllable accuracy. A novel high-order method is introduced for the thin-wire problem. The method is posed in a Galerkin form. A simple transformation is then applied that leads to a point-matched form of the operator, subsequently eliminating the outer integration. Through numerical examples based on both scattering of thin wires and antenna radiation, it is demonstrated that the method leads to true high-order convergence.