Implementation of a simplified form of CMP-EFIE for low-frequency capacitive problems

In this paper, a simplified form of electric field integral equation with Calderón multiplicative preconditioner (CMP-EFIE) is presented for solving capacitive problems in the low-frequency regime. The decomposed three-term CMP-EFIE, though very stable, cannot capture the current accurately for a capacitor at low frequencies. By omitting the part of the hypersingular preconditioned term, the electric currents solved from the remaining two terms are of the right frequency order for a capacitor. Hence, the resultant two-term formulation can guarantee the accuracy of results for capacitive problems, and also makes the iterative system more stable at low frequencies. Both theoretical analysis and numerical results are provided to verify the practicality of the proposed method.