A Novel Low-Profile Circularly Polarized UHF Crossed Dipole Antenna

In this paper, a novel low-profile circularly polarized crossed dipole antenna operating at UHF band, with small dimensions of 180 mm x 160 mm x 4 mm (0.22 lambda x 0.20 lambda x 0.005 lambda) where lambda is the wavelength corresponding to resonant frequency 370MHz, is proposed. Meandering lines are designed to reduce the size of the antenna. To achieve circularly polarized radiation pattern, a feeding network composed of a power divider and 90 degrees phase shifter is used. Besides, the ground of the feeding network serves as a half-ground for the radiation part. Finally, the antenna is modeled as the optimized version. It has good simulated realized gain with radiation efficiency about 80% to 90% at resonant frequency.