Low-frequency CMP-EFIE with perturbation method for open capacitive problems

This paper addresses the low-frequency problems for open capacitive problems in the electric field integral equation using Calderón multiplicative preconditioner (CMP-EFIE). At low frequencies, the CMP-EFIE fails to extract accurate high-order current for a capacitor problem. By representing the electric current at different frequency orders as a power series, we successfully apply the perturbation method on the CMP-EFIE for capacitive structures with open surfaces. Numerical results show that the highly accurate current for a capacitor can be obtained with fast convergence at extremely low frequencies.