Patent ID: 8525736

Claim:
An antenna device comprising: a base member, which is a wiring substrate, having a power feed point to which a power feed line is connected; an antenna element connected to the power feed point and erected on the base member; and a matching circuit section, which is connected to the power feed point and the antenna element, provided on the base member, and matches the reactance of the antenna element and that of the power feed line with each other, wherein the antenna element includes: an upstanding section extending from the base member in a direction perpendicular to the base member; a tuning section, which corrects directivity or polarization of a radiation signal, extending from the upper end of the upstanding section in a first direction in a plane parallel to the base member, bent or curved in the middle, and then extending in a second direction opposite the first direction; and an open element section extending from the front end of the tuning section in a direction in which the open element section spirally turns about the upstanding section in the plane parallel to the base member.