Patent ID: 8242963

Claim:
An antenna device comprising: a planar ground plate having a ground conductor; a first loop antenna and a second loop antenna provided at positions separate from the ground plate in a horizontal direction; and a signal feeding section that feeds signals to feeding points provided at one ends of the first loop antenna and the second loop antenna respectively, wherein loop planes formed respectively in the first loop antenna and the second loop antenna are perpendicular to the ground plate; wherein other ends of the first loop antenna and the second loop antenna are coupled to the ground plate respectively; wherein a turning direction of the first loop antenna from the feeding point thereof to the ground plate is opposite to a turning direction of the second loop antenna from the feeding point thereof to the ground plate; and wherein polarized waves parallel to the loop planes emitted from the first loop antenna and the second loop antenna are perpendicular to a polarized wave emitted by electric currents flowing from the first loop antenna and the second loop antenna into the ground plate.