Dual-Sleeve Monopole-Slot VHF Antenna for Naval Communications

This letter proposes the dual-sleeve monopole-slot very-high-frequency (VHF) antenna for naval multimode communications. The dual-sleeve monopole antenna, which is engineered as a vertical polarization element, operates from 30 to 100 MHz, the patterns are with omnidirectional features. The parasitic sleeve, built as waveguide slot antenna, mainly resonances at 80 MHz. The vertical polarization (VP) monopole antenna is offset fed, while the horizontal polarization (HP) slot antenna is probe fed between sleeves. Transmission line model is introduced to analyze the impedance match of slot antenna. A 10:1 scaled model of slot antenna is built and impedance and pattern measurements are conducted in anechoic chamber. Obtained results agree well with the simulations. Pattern of VHF antenna is measured by unmanned aerial vehicle (UAV) system loaded with portable spectrum analyzer. The mechanical and electrical integration strategy can be extended to other antenna typologies.