A comparison on face based and nodal based expansions for solving 3D EM scattering fields

Computation of three dimensional electromagnetic scattering from arbitrary bodies is of significant practical interest. Although the method of moments (MOM) is popular and provides rigorous solutions, its application is limited in many problems due to the cost of computer memory and CPU time. In solving the problem, the first step is the choice of basis functions no matter what computational strategy will be chosen to speed up the algorithm. In order to achieve stability in numerical computation, local interpolation and discrete transform scheme is suggested. The face elements is compared with nodal elements based on unified linear interpolation basis functions. It is shown that the space spanned by nodal basis is larger than that spanned by face basis. The trade-off among the completeness of the basis, the number of unknowns, and the CPU time based on the MOM is analyzed.