A physically concise circuit model for electrically small structures

In this paper, an numerical algorithm that can automatically derive a concise and physically intuitive equivalent circuit model for typical electrically small radiating structures is presented. Specifically, two short thin-strip dipoles and a small thin-strip loop are investigated in detail. The derived equivalent circuit for the short dipole is a lossy capacitor, whereas the one for the small loop is essentially a lossy inductor. These results confirm the conventional understanding that a short dipole is electric and a small loop is magnetic in nature. This algorithm, which is based on the PEEC technique, is particularly useful for analyzing electrically small radiating structures.