Radiation characteristics of HE/sub 11/-type wave from dielectric rod antenna with periodic surface

The radiation characteristics of HE/sub 11/-type wave in periodic rod waveguides is studied theoretically and experimentally. Based on the analysis results, a periodic rod antenna is designed and fabricated. The radiation pattern of the fabricated antenna is in reasonable agreement with the calculated values excluding the angles near the antenna axis. It is shown that a linearly polarized conical beam or a circularly polarized conical beam is radiated from the antenna.