Accurate evaluation of the Galerkin´s testing integrals for the triangular-type junction basis function

The numerical solution of electromagnetic radiation and scattering problems for complex bodies is often performed in terms of surface integral equations and the method of moments (MoM). The choice of the basis/weighting functions plays a critical role in determining the accuracy and efficiency of the method. For the treatment of arbitrary wire and surface configurations, it is worth mentioning, among others, the use of the triangular-type basis functions for modeling the current on surfaces (Rao, S.M. et al., 1982), wires (Hwu, S.U. and Wilton, D.R., 1988) and wire-to-surface junctions (Hwu et al., 1988). Efficient and reliable numerical procedures are proposed for the evaluation of the Galerkin testing integrals using the triangular-type wire-to-surface junction function. The 1/ρ singular behaviour of the testing integrands is removed before the evaluation, leading to two-dimensional integrations suited for its numerical implementation. The proposed procedure guarantees the reliable application of Galerkin´s formulation to the analysis of arbitrary configurations of wires and surfaces, using the Rao-Wilton-Glisson basis functions for surfaces (Rao et al., 1982) and their counterparts for wires and wire-to-surface junctions.