Patent ID: 7227509
Filing Date: 2007-06-05
Classification: H01Q

Abstract:
1. An antenna device having an open end, the antenna device comprising: four linear elements, each of which has a length equivalent to a half wavelength of an operating frequency, the elements being placed in a diamond shape on a plane, a feeding section that feeds power to one end of a first linear element and one end of a second linear element, the feeding section being put at one of the apexes of the diamond shape, a first delay section connected to the other end of the first linear element and one end of a third linear element for delaying the phase of an antenna current by a given phase, a second delay section connected to the other end of the second linear element and one end of a fourth linear element for delaying the phase of an antenna current by the same phase as that of the first delay section, and a reflector placed at a given distance in parallel to the plane, on which the linear elements have been placed.