A novel tailored coplanar waveguide circularly polarized antenna controlled by the gravity field.

In this article, a tailored coplanar waveguide (CPW) circularly polarized (CP) antenna is designed, whose operating band can be adjusted in a large range by the gravity field through rotating the antenna vertically. Due to the fluidity of liquid metal mercury, which is packaged in the antenna's glass containers, when the antenna is rotated, mercury will lead to different metal resonant units in different directions under the influence of gravity. This antenna utilizes CPW whose metal reflective surface and the main radiating patch are on the same side of the dielectric substrate. The dielectric substrate is made of FR4, and the metal radiation patch and the metal reflective ground are made of copper. Two metal branches separated from the main radiation patch are connected to the main radiating patch by a glass container. To verify concept of the design, equivalent prototypes have been fabricated and measured. The measured results are roughly consistent with simulated results within a reasonable error range. The measured results show that when the antenna turns 90° counterclockwise along the x‐axis (state I), the 10‐dB return loss bandwidth is 13.5% (4.54~5.2 GHz), and the 3‐dB axial ratio (AR) bandwidth is 13.8% (4.5~5.17 GHz). When the antenna turns 90°clockwise along the x‐axis (state II), the 10‐dB return loss bandwidth is 23% (3.73~4.7 GHz), and the 3‐dB AR bandwidth is 23% (3.73~4.7 GHz) within the antenna operating range. In the cases of two different working states, the proposed antenna can effectively cover the 5G communication band. [ABSTRACT FROM AUTHOR]