Antenna Device, Antenna System, And Instrumentation System

Abstract

An object of the present invention is to suppress occurrence of disturbance in pass amplitude characteristics within a band and disturbance in return loss characteristics in the band due to total reflection, improve cutoff performance, and acquire a favorable gain. An antenna device 1 includes a waveguide body 5 including a coaxial waveguide conversion unit 6 that is hexahedral and includes an inner space 8 formed by penetrating a first surface and a second surface facing each other and a connector attachment hole 22 for inserting a coaxial connector continuously formed between a third surface orthogonal to the first surface and the second surface and the inner space, and a closure member 30 that is conductive and closes an opening of the inner space on the second surface side. The antenna device 1 also includes a connector 50 including a connector body 51 attached to the connector attachment hole from the inner space toward outside, with an inner end thereof not protruding into the inner space, a center conductor 60 arranged to axially penetrate a central portion of the connector body, with an end portion thereof protruding from an inner end of the connector body into the inner space by a predetermined length, and a radiator 54b configured by an end portion 60a of the center conductor that adapts the protruding length of the end portion to a specific frequency band.

Dependencies are inferred from the claim text.