Patent ID: 7420511
Filing Date: 2008-09-02
Classification: H01Q

Abstract:
1. An antenna for multiple bands, characterized in that one end of an antenna element is electrically connected to a feeding point, said antenna element extending longitudinally from the feeding point to the other end thereof to obtain necessary electrical length for antenna operation, one ends of switches are connected respectively to at least one intermediate point and the other end of said antenna element, said intermediate point being a point on the longitudinally extending antenna element, the other end of one of these switches is connected to a ground conductor directly, the other ends of others of these switches are connected respectively to said ground conductor with an extension coil or a short capacitor inserted in series therebetween, different electrical lengths from said feeding point via said switches closed tip to electrical connections to said ground conductor are set to be capable of resonating different desired frequency bands respectively, and resonant frequencies with which different electrical lengths of said antenna element from said feeding point up to the connections to said switches resonate are set not to come close to one of said frequency bands with which the electrical length from said feeding point up to the connection to said ground conductor via any other switch closed resonates.