Patent ID: 6930640
Filing Date: 2005-08-16
Classification: H01Q

Abstract:
1. A dual frequency band inverted-F antenna for communicating a low frequency signal and a high frequency signal, comprising: a substrate; a ground metal, which is formed on a lower surface of said substrate; a vortical metal structure, which is formed on an upper surface of said substrate, further having a short circuit end and an open circuit end wherein said open circuit end is located within a center of said vortical metal structure; a short circuit leg, which connects electrically said short circuit end of said vortical metal structure with said ground metal; a feeding leg, which extends along a predetermined direction of said vortical metal structure to couple with a feeding circuit on said substrate; and a terminal micro strip, which is fabricated on the lower surface of said substrate and connected electrically to said open circuit end through a first conductive aperture; wherein, by increasing an encircling number of said vortical metal structure to generate a coupling effect so that an equivalent wavelength of said high frequency signal becomes longer and thereby a resonance frequency at a lower frequency band and a second frequency is added for communicating at a higher frequency band.