The electromagnetic properties of re-entrant dielectric honeycombs

Dielectric honeycombs are cellular materials often used in applications tha t require structural and electromagnetic characteristics, e.g., in LO (low observable) and radome components, A re-entrant (or auxetic) honeycomb is a cellular material with structural properties that are superior to those of a conventional honeycomb. By employing the finite-difference time-domain ( FDTD) technique with periodic boundary conditions, the electromagnetic prop erties of re-entrant honeycombs are determined and compared to those of a c onventional honeycomb. Re-entrant honeycombs are shown to have substantiall y superior electromagnetic properties. Measured permittivity data are used to substantiate the conclusions based on predicted FDTD data. The use of re -entrant honeycombs, rather than conventional honeycombs, in LO and radome applications can yield improved structural and electromagnetic performance.