Patent ID: 6680703
Filing Date: 2004-01-20
Classification: H01Q

Abstract:
An apparatus for tuning a circularly polarized patch antenna, wherein the circularly polarized patch antenna comprises a metal patch, a dielectric layer, a metallization layer, and a pin, the apparatus comprising:a first varactor, wherein a first terminal of the first varactor is coupled to the metal patch of the circularly polarized patch antenna at a first point and a second terminal of the first varactor is coupled to ground; a second varactor, wherein a first terminal of the second varactor is coupled to the metal patch of the circularly polarized patch antenna at a second point and a second terminal of the second varactor is coupled to ground; and a first capacitor, a second capacitor, a first resistor, and a second resistor, wherein the first capacitor and the first resistor are coupled to the first varactor, and the second capacitor and the second resistor are coupled to the second varactor, and a first voltage is applied to the first resistor to tune the first varactor and a second voltage is applied to the second resistor to tune the second varactor.