Patent ID: 6567055
Filing Date: 2003-05-20
Classification: H01Q

Abstract:
An apparatus comprising:a printed planar circuit board, having a predetermined thickness and a predetermined insulating material therein with a predetermined dielectric constant; said printed planar circuit board having a top circuit board side and a bottom circuit board side; a top side ground plane disposed on said top circuit board side; a bottom side ground plane disposed on said bottom circuit board side; said top side ground plane having a top side unplated void therein; a top side microstrip feed line extending through said top side unplated void; a top side balun trace is coupled to said top side microstrip feed line and extends beyond the top side void; a bottom side balun trace is coupled to said bottom side ground plane; and, said top side balun trace and said bottom side balun trace having a predetermined length characteristic, which is configured to provide a predetermined phase shift in a feed signal applied thereto.