Polarization- and Frequency-Reconfigurable Patch Antenna Using Gravity-Controlled Liquid Metal

This letter presents a reconfigurable antenna that uses gravity to control the self-circulation of liquid metal (LM), thereby realizing an adaptive reconstruction method. Then the polydimethylsiloxane (PDMS) structure with a square ring channel is loaded on the microstrip antenna, and the contact position between the liquid metal and the patch is controlled by gravity, which provides conditions for reconfiguration. The antenna has four reconfigurable frequency bands, which can be switched between the dual circle polarization (left- and right-hand circular polarization) mode and the linear polarization (LP) mode without additional mechanical adjustment structures, radio frequency circuits or related components. The measured results show that the proposed antenna has −10 dB impedance band of 1.2-1.6 GHz, 2.5-2.75 GHz, 4.2-4.55 GHz and 5-5.4 GHz and peak gain of 3.6 dBi, 5.07 dBi, 2.68 dBi and 3.25 dBi within passband, which agree well with the simulated results.