Abstract: The finite-difference frequency-domain (FDFD) equations of electronic field nodes are derived by differentiating the Helmholtz equation, based on the distribution of electric field nodes in Yee cells. Based on the equivalence principle, the incident wave is introduced in the total-field region by setting equivalent electromagnetic currents on the total-field/scattered-field (TF/SF) boundary. The FDFD equations of the nodes located near the TF/SF boundary are modified to fulfill the conditions that all nodes involved belong either to the total-field or to the scattered-field. The method is validated by comparing the amplitude and phase of the surface current on a perfectly electronic conductor cube, which are calculated by the FDFD method, with the result presented in the literature.

Key words: FDFD method, electromagnetic scattering, complex targets, TF/SF technique