Compact Circularly Polarized Antenna Based on Gapwaveguide for SATCOM Applications

In this study, a compact circular polarized antenna element based on gap waveguide has been introduced. The element is based on the compact quad ridge concept which allows a significant reduction in size for our proposed design compared to other conventional waveguide-based CP antenna designs. This compactness not only facilitates the design of more simplified individual components but also sets the way for the development of more compact arrays for the purpose of larger scanning angles in scanning array antennas. The dimensions of the antenna element is
$6.58\times 6.58\mathbf{mm}$
at a center frequency of 28.5GHz. The impedance bandwidth ranges from 27.75GHz to 29.75GHz and the axial ratio is less than 3dB, aligning with the impedance matching with a bandwidth of 5.08%. The design has low loss and high efficiency due to its fully metal structure. Given its inherent attributes and performance metrics, this compact cavity emerges as a promising choice for Satellite Communication (SATCOM) applications.