A Frequency- and Polarization- Reconfigurable Slot Antenna Using Liquid Metal

In this communication, a microfluidically frequency- and polarization-reconfigurable slot antenna using liquid metal (LM) is proposed. The polydimethylsiloxane (PDMS) structure with narrow-banded microchannels is loaded on the printed circuit board (PCB) of a square slot antenna, providing condition for reconfiguration. The left-hand circular polarization (LHCP), right-hand circular polarization (RHCP), and linear polarization (LP) are achieved by injecting LM into +45° and −45° channels with respect to the $x$ -axis or keeping the channels empty. Three operating frequency bands of LHCP and RHCP states can be realized by filling the microchannels with different lengths. Both states have an overall tuning 3 dB axial ratio bandwidth (ARBW) of 26.42% (2.3–3 GHz). In LP state, the proposed antenna realizes a −10 dB impedance bandwidth of 11.6% (2.03–2.28 GHz). A prototype of the proposed antenna has been fabricated and measured. Good agreement between the simulated and measured results validates the feasibility of this technique.