Patent ID: 8902117

Claim:
An antenna apparatus comprising: a dielectric substrate having first and second surfaces; a dipole antenna including a first feed element formed on the first surface of the dielectric substrate and connected to a feeder line, and a second feed element formed on the second surface of the dielectric substrate and connected to a ground conductor, the dipole antenna having an electrical length of substantially ½ of a wavelength of a high-frequency signal to be radiated; and at least three first parasitic element arrays, each of the first parasitic element arrays including a plurality of first parasitic elements formed on the first surface of the dielectric substrate, wherein, in each of the first parasitic element arrays, each of the plurality of first parasitic elements has a strip shape substantially parallel to a longitudinal direction of the dipole antenna, and the plurality of first parasitic elements being arranged at predetermined first intervals so as to be electromagnetically coupled to each other, and wherein the at least three first parasitic element arrays are arranged substantially parallel to one another at predetermined second intervals so that each of first pseudo-slot openings is formed between each pair of adjacent first parasitic element arrays, the first pseudo-slot openings allowing a radio wave from the dipole antenna to propagate therethrough as magnetic currents.