Enhancement of Electric Field in E-plane Sectoral Horn Antennas Reconsidered by Plasmonic Theory

Plasmonic theory is applied to the E-plane sectoral horn antennas discussed in microwave technology where metals is treated as perfect conductors approximately. The theory enables us to reconsider the sectoral horn antennas with a finite metallic permittivity for more realistic estimation of an enhancement factor of electric field that enters at the mouth of the sectoral horn antennas through the throat to the parallel- plate waveguide as a limit case of the rectangular waveguide.