A novel low-profile circularly polarized UHF crossed dipole antenna

Abstract

In this paper, a novel low-profile circularly polarized crossed dipole antenna operating at UHF band, with small dimensions of 180 mm × 160 mm × 4 mm ( 0.22 λ × 0.20 λ × 0.005 λ) where λ 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° 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.