A Novel Circularly Polarised Antenna With Wide Power and Axial-Ratio Beamwidth by Using Tilted Dipoles

Abstract

Abstract-A novel circularly polarised antenna with wide 3 dB axial-ratio beamwidth (ARBW) and half power beamwidth (HPBW) is proposed in this letter. By using two pairs of tilted dipoles, the ARBW of the antenna is significantly enhanced to about 160 • and 162 • in the XZ-and Y Z-planes, respectively. Meanwhile, its HPBW is also broadened to above 116 • in the dual planes. A prototype is manufactured and measured to validate the method. The measured results show that |S 11 | < −10 dB reaches about 38.8% (1.37 GHz-2.03 GHz), and the AR at broadside bandwidth is 14% (1.51 GHz-1.74 GHz). The gain of the antenna also keeps above 4.19 dBic. Meanwhile, acceptable agreements can be obtained between the simulated and measured results. As such, the proposed CP antenna with wide beamwidth can be used in various navigation systems.

A Study of Designing Circular Polarization for Leaky Coaxial Cable at 900 MHZ

“…where E max and E min are the maximum and minimum values of the instantaneous electric field, and they are also the long and short axes of the polarized ellipse [10]. It is generally considered to be circular polarization when the axial ratio AR < 3 dB.…”