DIELECTRIC ROD ANTENNA

PURPOSE:To provide a dielectric rod antenna, for which the directional characteristics of a magnetic field plane and an electric field plane are almost equal, and to reduce a side lobe by providing a conductor on the outer peripheral face of a dielectric rod. CONSTITUTION:A dielectric rod antenna 1 is composed of a dielectric rod 2, waveguide 10 and radome 12, the lateral crosssection of the dielectric rod 2 is made circular, and resin or ceramics is used as the material. On the other hand, the terminal part of a base terminal part 2a of the dielectric rod 2 is projected in the shape of a corn and gradually thinned from the base terminal part 2a provided with the maximum diameter of the dielectric rod 2 to a tip part 2b, and a conductive film 4 is provided in the shape of a circular ring on the outer peripheral face inclined from the base terminal part 2a to the tip part 2b. Then, the base terminal part 2a of the dielectric rod 2 is inserted to one opening part 110b of the waveguide 10 of a conductor housing, a detecting terminal is arranged at another opening part 10a of the waveguide 10 and further, the resin radome 12 is fitted to this waveguide 10.