This work describes the fabrication and characterization of a frequency reconfigurable patch antenna using ferrofluid actuation. The reconfiguration is based on a variation of dielectric constant of the substrate. For this, the substrate is modified by placing channels in it filled with ferrofluid and isopropanol-water solution. The relative position of ferrofluid along the channels is controlled by an external magnetic field which results in a relocatable spatial difference in the dielectric constant value. The targeted reconfigurability with stable radiation characteristics at the accessible frequencies is validated through antenna reflection loss and radiation pattern measurements. Additionally, actuation speed of the fluid immerged in the polar mixture is measured by sequential image analysis.
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