Patent ID: 7764238

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 is connected to the feed side element, has a second end being open, and extends from a contact point connected to the feed side element in the direction in which the first open-ended element extends, the contact point being a second end of the feed side element; 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 feed point through an outer edge of the feed side element including the edge close to the ground and the short circuit element to the second end of the first open-ended element, is substantially a quarter of a wavelength of a first resonant frequency, and a length, from the feed point through the outer edge of the feed side element including the edge close to the ground to the second end of the second open-ended element, is substantially a quarter of a wavelength of a second resonant frequency.