Patent ID: 7982678

Claim:
An antenna device comprising: a short circuit path, a first end of which is connected to a ground point that is located near a feed point; a first open-ended element that has a second end being open, and extends from a second end of the short circuit path; a feed side element that extends from near the feed point in a direction in which the first open-ended element extends to have an edge close to ground; a second open-ended element that has a second end being open, and extends from a point connected to the feed side element in the direction in which the first open-ended element extends; and a short circuit element that connects between a first end of the first open-ended element and either a point on an edge of the feed side element opposite the edge close to the ground or a point on the second open-ended element, wherein a length, from the ground point to the second end of the first open-ended element through the short circuit path and the first open-ended element, is substantially a quarter of a wavelength of a first resonant frequency, and a length, from the ground point to the second end of the second open-ended element through the short circuit path, the short circuit element, and the second open-ended element, is substantially a quarter of a wavelength of a second resonant frequency.