Thin-Slot Formalism For The Split-Field Fdtd Analysis Of Periodic Structure

An expression of the thin-slot formalism is presented to alleviate the gridding of the split-field finite-difference time-domain (FDTD) solution for periodic structure. The varying auxiliary-field ((P) over bar, (Q) over bar) and split-field ((P) over bar (a), (Q) over bar (a)) distributions near the slots are analytically derived from the varying field ((E) over bar, (H) over bar). The update equations for the split-field FDTD are obtained by incorporating those varying field distributions into the split-field equations in integral form. A frequency selective surface (FSS) structure is applied to verify the proposed method. The results indicate that the computational efficiency is improved.