Balanced tangential testing for the nonconforming discretization of the Electric-Field Integral Equation on open PeC surfaces

Abstract

Recent attention has been devoted to the development of nonconforming implementations of the Electric-Field Integral Equation (EFIE), which impose no continuity constraints in the expansion of the current between adjacent facets. These schemes, based on the facet-oriented monopolar-RWG set, become more versatile than the traditional edge-oriented schemes, based on the RWG set, because they simplify the discretization around junctions in composite objects and because they can handle nonconformal triangulations. The existing nonconforming implementations tackle the numerical evaluation of the inherent hypersingular Kernel contributions of the EFIE by testing the fields over volumetric or surface domains attached to the boundary surface inside the conductor. Hence, the application of such schemes is restricted to closed PeC surfaces. In this paper, we present a novel nonconforming implementation of the EFIE that allows the scattering analysis of open PeC surfaces by testing the fields with a new, 'balancedtangential', strategy. We show for several examples of open PeC surfaces, infinitely long (2D) or arbitrarily shaped (3D), that the proposed scheme provides similar or slightly better accuracy than the RWG-discretization of the EFIE and same meshing.