Modular All-Metal Ultrawideband Cylindrical Array for Multifunction Operation

Legacy cylindrical phased array systems are constrained to narrowband operation due to antenna element limitations amid a growing need to support advanced multifunctional platform requirements. In this article, a notch-based all-metal ultrawideband (UWB) antenna element suitable for cylindrical arrays is introduced. The proposed element is designed to operate over 2.75–10 GHz while being highly amenable to a cylindrical architecture via modularized assembly of compact scalable column facets. The primary enabling technical innovations are: 1) a new shunt-loaded stepped-impedance (SI) gap design scheme to improve low-frequency performance without increasing profile and 2) the design of a tongue-and-groove azimuthal crosswall that precisely conforms to the wedge-shaped unit cell for simple yet robust cylinder assembly. For a proof-of-concept demonstration, a 120° sector array is built having a
$12^{\prime \prime }$
outer diameter and 21 columns—each comprising eight single-polarized elements (168 total feed points). Measurements are presented for active phase-mode impedance and embedded element patterns of a central element, demonstrating good agreement with full-wave simulations.