A Frequency-Reconfigurable Dielectric Resonator Antenna With a Water Layer

This letter introduces a frequency-reconfigurable dielectric resonator antenna (DRA) with water layer integration. The proposed method is based on the strategy combination of mode reconfiguration and dielectric loading. First, the frequency band of the DRA is reconfigured between the resonant frequencies of the fundamental
$TE_{111}^y$
and quasi-
$TE_{113}^y$
modes by flowing liquid control of water pumping in and out of the microfluidic cavity. Then, the frequency response of quasi-
$TE_{113}^y$
mode is continuously swept by altering the thickness of water layer. For demonstration, the DRA is designed with a solid dielectric material of K9 glass with the permittivity of 6.25 and loaded with a layer of fresh water with the permittivity of 77. Finally, the proposed antenna is fabricated and measured, which performs with a wideband reconfigurability and stable far-field performance corresponding to the different frequency responses.