A Frequency Reconfigurable Patch Antenna Based on Liquid Crystal

A frequency reconfigurable patch antenna based on a liquid crystal (LC) is proposed in this study, and the patch is positioned above the LC. DC bias voltage is applied to both sides of the LC. The permittivity of the LC changes with the DC bias voltage so that the resonant frequency is reconfigurable. The direct current (DC) bias voltage and the radio frequency (RF) signal can be isolated since the patch is fed by an aperture-coupled microstrip feed line. Thus, the DC bias voltage can not influence the RF signal. The presented antenna is simulated, fabricated and measured. The simulated resonant frequency spans the 7.28 to 7.38 GHz range, whereas the measured resonance frequency spans the 7.28 to 7.36 GHz range. The measured reflection coefficients are compared with simulated reflection coefficients for the proposed antenna. The comparison shows that the frequency reconfigurable patch antenna based on a liquid crystal (LC) is feasible.