Wide-beam circularly polarized composite cavity-backed crossed scythe-shaped dipole

In this paper, a wide-beam circularly polarized (CP) composite cavity-backed crossed scythe-shaped dipole is proposed. Each dipole arm contains a meander line whose end is shaped like a scythe chine to accomplish a significant reduction in the radiator size. The scythe-shaped dipoles are crossed through a 90° phase delay line of a vacant-quarter printed ring in order to generate CP radiation and broadband impedance matching. The crossed scythe-shaped dipole is incorporated with a cavity-backed reflector to improve the radiation pattern in terms of the CP radiation beamwidth and front-to-back ratio. The proposed antenna yields broad impedance-matching and 3-dB axial-ratio bandwidths, a high front-to-back ratio, and a wide beamwidth.