Performance enhancement of cross dipole circularly polarized antenna using parasitic elements

Abstract

Abstract This study designs a wideband circularly polarized (CP) cross dipole antenna (CDA) with modified characteristics. The CP CDA consists of four quarter disks, four sector rings, four rotated grounded metal sheets and a pair of vacant quarter rings as a continuous‐phase feeding geometry. In contrast to the conventional vacant quarter rings, the modified vacant quarter rings increase the impedance bandwidth (IBW) and provide a 90° phase difference to obtain CP radiation. In addition to exploiting the quarter disks and sector rings to broaden the CP bandwidth, grounded metal sheets are utilized to widen the CP bandwidth of the proposed antenna. By utilizing the multiple CP resonant modes excited by these elements, the CP bandwidth of the antenna can be improved. As a result, the proposed antenna exhibits broad –10‐dB IBW of 109% (2.13, 0.97–3.29 GHz) and a wide 3‐dB axial ratio bandwidth of 88.9% (2.34, 1.30–3.38 GHz).