A Comparison of Higher Order Nodal- and Edge-Basis Functions in the MFIE on Rational BÉzier Geometries

Higher order nodal basis functions for representing equivalent surface currents on antennas and scatterers are introduced. The performance of the nodal basis is evaluated by comparing two existing higher order edge bases, using the magnetic field integral equation (MFIE) formulation for scattering by a perfect electric conductor (PEC) sphere and icosahedron as test problems. Both nodal and edge bases are implemented on rational Bezier patches, giving an exact representation of the surfaces, free from geometrical error. The accuracy of the numerical solutions obtained with the three different bases for both the surface current and the radar cross section (RCS) are compared, and it is shown that in general the nodal bases give better accuracy than the edge bases for equal computational cost.