A Frequency Reconfigurable Circularly Polarized Antenna Based on Liquid Metal

A frequency reconfigurable circularly polarized antenna using liquid metal is proposed in this letter, the antenna is composed of a truncated-corners square slotted patch and a slot-microstrip coupling structure. The method for designing a circularly polarized radiation patch and the fluidity of liquid metal is used here: 1) introducing four corner cuts and a rectangular slot to realize the circular polarization characteristics; and 2) injecting the liquid metal into different zones to control the operating frequency of the antenna. The simulation results show that the proposed circularly polarized antenna can be tuned to work in three different frequencies.