Patent ID: 6285340
Filing Date: 2001-09-04
Classification: H01Q

Abstract:
A dual band helical antenna comprising:a first dielectric core having a substantially cylindrical shape with an outer circumferential surface on which a first spiral groove is formed;a first conductive strip deposited on the first spiral groove and having a length of one-fourth of a first wavelength;a second dielectric core, positioned under said first dielectric core, having a substantially cylindrical shape with an outer circumferential surface on which a second spiral groove is formed;a second conductive strip deposited on the groove of said second dielectric core, electrically connected to said first conductive strip, and having a length of one-fourth of a second wavelength;a feeding conductor, placed under said second dielectric core, for providing an electrical connection between said second conductive strip and an external circuit; andan antenna cover for enclosing said first and said second dielectric cores and said feeding conductor.