Liquid Waveguide Antenna

A novel concept of liquid waveguide antenna (LWA) is proposed in this paper. An X-band liquid rectangular waveguide is demonstrated as an example for concept verification. A hollow-wall dielectric rectangular waveguide with standard aperture size is firstly designed and realized by 3-D printing technique. Subsequently, two rectangular metal rings are employed to seal the two waveguide ports so as to constrain liquid inside the waveguide. Conductive fluidic material is therafter filled into the hollow-wall rectangular waveguide to form the LWA. Simulation results verified that the proposed liquid rectangular waveguide has similar electromagnetic properties compared with traditional solid metal rectangular waveguides. Eventually, a Bull's eye waveguide antenna is designed to further demonstrate the feasibility of the proposed LWA.