A Cavity-Backed Polarization Reconfigurable Antenna Based on Liquid Metal

This paper proposes a frequency and polarization reconfigurable dual-band antenna using liquid metal. The radiating part of the antenna consists of two orthogonally printed strip dipoles with consistent shapes and liquid metal. The two intersecting dipoles are fed by a coaxial cable, and the liquid metal is enclosed in channels made of polytetrafluoroethylene (PTFE). By utilizing the fluidity of liquid metal to change its position, the antenna can achieve linear polarization operation within the frequency range of 1.54 GHz to 1.87 GHz and 2.24 GHz to 3.02 GHz. In the circular polarization mode, its impedance bandwidth covers 1.51 GHz to 1.69 GHz, and the axial ratio bandwidth is 1.62 GHz to 1.74 GHz. To further enhance the performance of the antenna, four corner parasitic patches are introduced between the two intersecting dipoles. At the same time, the cavity-backed reflector of the antenna ensures its powerful directional radiation characteristics and improves gain. According to simulation results from the CST Microwave Studio®, the antenna achieves the peak gain of up to 9.92 dBi.