Z-shaped monopole antenna for wideband circularly polarized radiation

This paper presents a Z-shaped printed monopole antenna for wideband circularly polarized radiation. The antenna consists of a Z-shaped strip radiator fed by a microstrip line attached the Z-shaped strip. The antenna is fabricated on a thin FR4 dielectric substrate. The measured performances of the antenna are 1.28 GHz (2.53-3.81 GHz) for 10-dB return loss bandwidth, 1.75 GHz (2.25-4.0 GHz) for 3-dB axial ratio bandwidth, and gain around 1.7 dBic over the 3-dB axial ratio bandwidth. The volume of the proposed antenna is 50 mm × 40 mm × 0.8 mm.