Higher-order MoM implementation to solve integral equations

Higher-order basis functions have received intensive attention for solving electromagnetic problems with the finite element and Galerkin´s methods. The advantage of using higher-order basis functions lies in their ability to model the fields and sources, as well as geometries, more accurately than conventional low-order methods. We investigate the convergence properties of divergence conforming interpolatory higher-order basis functions for evaluating the Galerkin´s solution of integral equations. Both the electric field integral equation (EFIE) and the magnetic field integral equation (MFIE) are used to obtain the scattered field from perfectly conducting objects. Our solution is first validated by comparing the radar-cross section (RCS) with the corresponding Mie series solution for conducting spheres. Next, we calculate the error convergence of the RCS from objects such as spheres and plates for several orders. In the case of objects with no analytical solution such as plates, over discretized solution is taken as the reference solution and the error results are then calculated.