Frequency-reconfigurable water dielectric resonator antenna

A frequency-reconfigurable water dielectric resonator antenna (DRA) with a wide tuning frequency range is presented in this paper. The design concept of the proposed antenna is based on combining a wideband feeding structure with a frequency-reconfigurable radiating structure. A water resonator contained by an acrylic box is used as the frequency-reconfigurable radiating structure. Meanwhile, a fixed conical probe is used as the wideband feeding structure to excite TE₂₁₁^y and TE₁₂₁^x modes of the rectangular water resonator. The operating frequency of the antenna can be easily tuned by changing the height of the water resonator. A prototype antenna is fabricated and measured results verify the proposed design concept. It is shown that the proposed antenna has a continuous tuning frequency range from 165 MHz to 700 MHz.