Patent ID: 6653988
Filing Date: 2003-11-25
Classification: H01Q

Abstract:
A parallel resonance antenna comprising:a whirl antenna having a plurality of antenna units installed two-dimensionally and radially around a central point, each of the antenna units having a ground point at a predetermined position thereof, portions outside the ground points respectively being bent in a same direction, the antenna units having a same size and direction, angles between the antenna units at the central point being all the same; a central conductive line connected to the central point to be normal to the whirl antenna, for being supplied with an RF power; a metal plate installed over and apart from the whirl antenna, the metal plate being connected with end portions of the antenna units, and having a penetration hole through which the central conductive line passes without contacting with the metal plate; and a variable resonance capacitor installed in series between the central conductive line and the metal plate.