A New Design Approach for Circular Polarize Antenna with DGS Under The Unbalanced Feed-Lines

摘要

A novel design approach is offered to attain circular polarization of the microstrip antenna feeds by unbalanced vertical feed-lines. Usually, diagonally balanced-line feeds with hybrid coupler are used to attain circular polarization. Here, Defected-ground structures (DGS) have been implemented under the unbalanced feed-lines to achieve circular polarization. Adopting DGS makes easy to tune antenna for circular polarization by varying the impedance of the feed-lines.