Crossed-dipole antenna

Abstract

Provided is a crossed-dipole antenna that can communicate at a plurality of frequencies, and has a simple structure that can be miniaturized. The crossed-dipole antenna is provided with a core composed of a dielectric material, a reflecting plate, a first element group composed of four first elements that are formed on an outer surface of the core, extend from a central portion of the top surface of the core with a first length L, and are arranged to be orthogonal to one another, a second element group that resonates at a second resonance frequency fand is composed of four second elements that are formed on the outer surface of the core, extend from the central portion of the top surface of the core with a second length L, and are arranged to be orthogonal to one another, and feeders that transmit electric power to each element. Each of the first elements and the second elements extends along the outer surface of the core and is bent from the top surface to the side surface. The first length Lof the first elements is less than a fourth of a first wavelength λcorresponding to the first resonance frequency f, and the second length Lof the second elements is less than a fourth of a second wavelength λcorresponding to the second resonance frequency f