Patent ID: 6204827
Filing Date: 2001-03-20
Classification: H01Q

Abstract:
An antenna feeding circuit comprising:a cylindrical body;said cylindrical body having an inner and an outer surface;an inner conductor disposed on the inner surface of the cylindrical body;one or more pairs of electrically conductive bands disposed on the outer surface of the cylindrical body at a position symmetrical with respect to the axis of the cylindrical body so as to be parallel with the longitudinal direction of the cylindrical body, wherein each of electrically conductive bands has a first end and a second end for connecting an antenna element of a helical antenna;one or more 180 degree distributors, connected to the first end of each of the band conductors, for supplying electric current to each of the band conductors through the first end, so that the phase difference between the electric currents in the band conductors is 180 degrees;wherein each of the electrically conductive bands induce an inverse inutile current in the inner conductor.