A Polarization-Reconfigurable Antipodal Dipole Antenna Using Liquid Metal

A polarization-reconfigurable antipodal dipole antenna is presented. The antenna switches between two orthogonal linear polarizations using low-power electrical actuation of liquid metal. Previous electrically actuated liquid-metal antennas have required continuous applied voltages to maintain an operating state, and had reduced gain from exposure to the lossy electrolyte needed for actuation. This antenna uses metastable locking so that applied voltages are only needed to change operating states, not to maintain them. In addition, the compact design of this antenna reduces the amount of electrolyte, and the antenna performance with and without the electrolyte solution is quantified. The dipole has a maximum gain between 1.8 and 2.3 dBi in the presence of the electrolyte and between 2.4 and 3.0 dBi when the solution is removed. The resonant frequencies of the orthogonal polarizations are less than 5.3% apart, and all states have greater than 15-dB return loss at the 3-GHz operating frequency.