A novel circular-polarized array antenna based on substrate integrated waveguide for satellite communication

A circular-polarized array antenna having a novel feeding structure like a substrate integrated waveguide(SIW), SIW-based power divider, and sequentially rotated cavity-backed single element is proposed for satellite communication and enhancement of electrical performances in a double-layered fabrication. The bandwidth enhancements in terms of CP generation and broadband impedance matching characteristics are accomplished by using a fixed phase shifter and simple shorting via between the top patch and bottom ground plane. In addition, a broadband impedance bandwidth of 10% and a RHCP axial ratio of 5.7% have been obtained under the condition of less than VSWR 2:1 and axial ratio −3 dB, respectively.