Patent ID: 8912958

Claim:
A radio communication device which is inserted into an expansion slot of an electronic device, comprising: a printed circuit board having a rectangular shape with opposed short sides and opposed long sides, and provided with a connection terminal on one short side that connects to the expansion slot; an antenna element provided on the printed circuit board extending in a direction orthogonal thereto in the vicinity of the other short side of the printed circuit board, and having a substantially λ/4 electrical length, the antenna element being located at a position separated from a ground pattern of the printed circuit board by a distance substantially equal to λ/8 in electrical length; and at least three radial lines extending outwardly from the antenna element on the printed circuit board, the three radial lines having a similar length to each other, wherein a first of the radial lines extends from the antenna element toward the other short side, a second of the radial lines extends from the antenna element toward one of the long sides, and a third of the radial lines extends from the antenna element toward the other of the long sides, wherein the second and third radial lines are orthogonal to the first radial line.