A Broadband Hybrid Monopole-Dielectric Resonator Water Antenna

A broadband hybrid water antenna operating at very high frequency (VHF) band is presented, in which a simple seawater monopole is loaded with two distilled water cylinders working as dielectric resonators (DRs). By employing the loading technique, multiple close resonances are introduced to broaden the impedance bandwidth of the seawater antenna. The hybrid water monopole-DR antenna is designed, simulated, fabricated, and measured. The simulated and measured results have a good agreement. A wide bandwidth from 69 to 171 MHz for $| {{{S}_{11}}} | < - 10\,{\text{ dB}}$ is achieved. Meanwhile, the radiation patterns are stable in the desired band, which indicates that the proposed antenna is suitable for broadband application in VHF band communications.