Patch antenna adjustable in frequency based on polymer dispersed liquid crystal
A frequency reconfigurable antenna with a liquid crystal polymer as the dielectric substrate is designed to realize the impedance matching of the antenna by adjusting the position and size of the patch.A polymer-dispersed liquid crystal film is prepared as the medium of the antenna,and its effect is examined on the basis of various liquid crystal to polymer ratios and film thicknesses.Under the action of an electric field,the formed liquid crystal microdroplets are reoriented and arranged along the direction of the electric field.The frequency reconfigurable antenna is then realized by changing the magnitude of driving voltage.After comparative analysis,it is concluded that the polymer-dispersed liquid crystal film with a liquid crystal content 70%(mass fraction)has the best effect,achieving continuous frequency adjustment of 62 MHz under a driving voltage of 48 V,and the maximum gain of the antenna is 3.5 dBi.This frequency reconfigurable patch antenna based on liquid crystal polymer is simple in structure,small in size,light in weight,and is easy to be integrated into a variety of mobile devices,which has a promising future for development.