Investigation on the numerical performance of Calderón Multiplicative Preconditioner for electromagnetic scattering and radiation of 3-D open perfect electric conductors

Numerical performance of Calderón Multiplicative Preconditioner (CMP) for the electrical field integral equation (EFIE) of 3-D open perfect electric conductors (PECs) is investigated in this paper. The iteration count for achieving convergence in iteratively solving MoM linear equations from CMP preconditioned EFIE of several PEC scatters or antennas are presented. Numerical experiments show that for the analysis of thin wire-like open PECs especially in certain electric field excitation condition where the induced surface current is mainly along the wire axis, the CMP may be unfortunately helpless to iterative solver in handling EFIE-MoM linear equations. Empirical analysis is addressed that the invalidation of CMP in these cases is due to the fact that the RWG functions have weak ability to simulate surface currents with rotational component.