Patent ID: 8154459

Claim:
An antenna device included in a radio apparatus having a printed board, comprising: a ground conductor provided in the printed board; a first sub-element formed as an area having a first side and a second side crossing each other, the first side facing a side of the ground conductor, and the first sub-element having a feed portion at a crossing of the first side and the second side, wherein the first side, the second side, and the ground conductor extend along a same plane; a second sub-element formed to branch off from the first sub-element around an end of the second side which is farther from the crossing, the second sub-element having an open end, and the second sub-element being directed at least partially in a direction opposite a direction from the crossing to an end of the first side opposite the crossing; and a short circuit element short-circuiting the first sub-element with the ground conductor, wherein the short circuit element branches off from the first sub-element at a point between the feed portion and the end of the second side which is farther from the crossing, and wherein a width of the first sub-element is greater than widths of the second sub-element and the short circuit element, and wherein the area of the first sub-element is greater than areas of the second sub-element and the short circuit element.