Ultrawideband Low-Profile Metal–Dielectric Additively Manufactured Planar Vivaldi-Shaped Antenna Array for Millimeter-Wave Applications

This communication presents an ultra-wideband (UWB) metal-dielectric additively manufactured planar Vivaldi shaped antenna array for millimeter-wave (mm-Wave) applications. Different from conventional end-fire Vivaldi antennas, the proposed design leverages a novel metal-dielectric synergistic additive-manufacturing process in which the exponential-tapered radiation part is deposited layer-by-layer with the dielectric. This integration not only planarizes the antenna while delivering low-profile ultra-wideband (UWB) broadside radiation performance but also lends itself to expansion into a high-gain array. Meanwhile, the feeding network is implemented on a separate PCB substrate and integrated with the additively manufactured Vivaldi shaped radiation part through the coupling slots, ensuring high radiation efficiency. To validate this design, a 4×4 antenna prototype with only a size of 2×1.72×0.11 λ<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">_low</i><sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> was fabricated and measured. The measured results demonstrate a -10 dB impedance bandwidth (IMBW) exceeding 100% (15.5 - 50 GHz), which spans the entire <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">K</i>- and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Ka</i>-bands, and realizes a peak gain of 17 dBi. By merging traditional PCB processes with advanced additive-manufacturing techniques, this design achieves a customized layout and superior performance, which establishes a novel path for next-generation high-performance mm-Wave applications.