3-D Printed Circularly Polarized Ceramic Dual-Loop Antenna with Axial Ratio Bandwidth Enhancement

In this paper, a 3-D printed circularly polarized (CP) ceramic dual-loop antenna with axial ratio bandwidth (ARBW) enhancement is proposed. Leaky-wave radiation of high-permittivity dielectric waveguide is here utilized to complete the proposed design. The design process of proposed dielectric antenna is here discussed in detail, which is bending the straight dielectric waveguide into loop structure to generate CP radiation, and then adding an extra loop to form a dual-loop structure for wider operational frequency band. It is found that the ARBW of the dual-loop antenna is about three times than that of the single-loop one. 3-D printing technology is adopted for precise manufacturing of the proposed ceramic dual-loop antenna. The measured ARBW covers from 3.94 to 5.1 GHz, with the maximal radiation gain of 8.6 dBic.