Patent ID: 8866678

Claim:
A patch antenna device comprising: a rectangular dielectric plate having long sides and short sides; a planar emission electrode disposed on one surface of the rectangular dielectric plate; a grounding electrode disposed on another surface of the rectangular dielectric plate; and a power supply member electrically connected to the planar emission electrode; wherein: the planar emission electrode is provided with three slits at a position corresponding to one short side of the rectangular dielectric plate and three slits at a position corresponding to another short side of the rectangular dielectric plate, the slits at each position extending toward an opposing one of the short sides and being arranged symmetrically, the slits at each of the positions are orthogonal to the short sides of the dielectric plate, and a length of a center slit among the three slits at each position is shorter than lengths of the other slits, and a power supply position of the power supply member to supply electric power to the planar emission electrode is deviated from a center of the planar emission electrode so as to obtain circular polarization characteristics.