Abstract: An antenna assembly suitable for use with a microwave-based level measurement system mounted on a vessel. The antenna assembly comprises a rod antenna having a mounting member with an integral sealing ring. The antenna is molded from a conductive polymer such as PTFE. The sealing ring is also formed from the same polymer as the antenna. The sealing ring may be formed as an integral component of the mounting member molded from a polymer material or as a separate ring element which is welded or otherwise affixed to the mounting member. The antenna assembly is coupled to the level measurement apparatus using a clamping mechanism. As the clamping mechanism is secured to the mounting member, the sealing ring is compressed and deflected and in the compressed state provides a seal between the level measurement apparatus and the section of antenna extending into the vessel. According to another embodiment, the antenna assembly is adapted for and mounted in a horn antenna.

Abstract: A dielectric rod antenna assembly for a level measurement system. The antenna assembly includes a transition structure housed within a coupling sleeve. The transition structure includes a short-circuited waveguide filled with a dielectric material and an exciter element projecting through the waveguide into the material. The transition structure directs electromagnetic energy through the bottom of the dielectric material into a rod antenna attached to the bottom of the coupling sleeve for propagation within the container. The dielectric material includes a longitudinal axial bore having a tapered tip to provide a dielectric-lined waveguide. The bottom end of the dielectric is encircled with a metal ring of a diameter larger than the dielectric to smooth the transition into the rod antenna.

Abstract: A dielectric rod antenna assembly for a level measurement system. The antenna assembly includes a transition structure housed within a coupling sleeve. The transition structure includes a short-circuited waveguide filled with a dielectric material and an exciter element projecting through the waveguide into the material. The transition structure directs electromagnetic energy through the bottom of the dielectric material into a rod antenna attached to the bottom of the coupling sleeve for propagation within the container. The dielectric material includes a longitudinal axial bore having a tapered tip to provide a dielectric-lined waveguide. The bottom end of the dielectric is encircled with a metal ring of a diameter larger than the dielectric to smooth the transition into the rod antenna.