Patent ID: 7271768

Claim:
A circularly polarized array antenna for receiving and transmitting a circularly polarized signal, comprising: a plurality of circularly polarized antennas with phase shift mechanism, for receiving the circularly polarized signal; a plurality of power lines, each of the power lines differing from each other in length and coupled to the circularly polarized antennas respectively; and a power divider, coupled to the power lines for receiving the circularly polarized signal from the circularly polarized antennas and transmitting the circularly polarized signal, wherein each of the circularly polarized antennas comprises a plurality of antenna elements and each of the antenna elements comprises a microstrip antenna and a slot coupling apparatus, wherein the slot coupling apparatus comprises a substrate and a slot antenna; an opening defined in the center of the substrate and forming a cuboid slot, a cross figure defined on an upper surface of the slot antenna, and a metal wire formed on a lower surface of the slot antenna.