A Circularly Polarized Water Patch Antenna

A circularly polarized (CP) water patch antenna is proposed in this letter. Both the patch and the ground plane are composed of distilled water. The water patch is in square shape with two diagonal truncated corners for generating CP radiation pattern. A metallic L-shaped probe is employed as the feeding portion. The entire configuration had been accomplished by a 3-D printed plastic container. Measured results show that the proposed CP water patch antenna can achieve a wide impedance bandwidth of 29%, a 3 dB axial-ratio (AR) bandwidth of 8.0%, a left-hand circular polarization gain up to 3.05 dBic, and a maximum radiation efficiency of 48% over the operating band. This presented design aims to demonstrate the feasibility of using distilled water to form the CP patch antenna. Besides, some parametric studies have also been carried out to investigate the performance characteristics, which significantly provide the design guideline for a range of CP water patch antenna designs in the future.