Low-profile crossed-dipole antenna loaded with parasitic patches

Abstract

This paper presents a low-profile, broadband, circularly polarized (CP) antenna. It is composed of a single-feed crossed dipole loaded with four parasitic patches. Due to the presence of parasitic patches, the antenna achieves a low profile and a broadband characteristic in terms of impedance matching and CP radiation bandwidth. The final design, which has an overall size of 120 mm × 120 mm 0╫ 16.3 mm (0.64λ0 × 0.64λ0 × 0.087λ0 at 1.6 GHz), yields a −10 dB impedance bandwidth of 1.39–1.75 GHz (22.93%), a 3-dB axial ratio bandwidth of 1.472–1.684 GHz (13.4%), a right-hand CP broadside gain of > 8.4 dBic, and a radiation efficiency of > 96%.