This paper presents a novel array that operates from the microwave to mm Wave regimes using the concept of tightlycoupled dipole arrays (TCDAs). The proposed antenna operates from 2-40 GHz while maintaining the low-cross polarization and scanning properties of TCDAs. Challenges associated with the realization of large bandwidth mmWave arrays were overcome by introducing a) new Y-junction ultra wideband feed, and by 2) assembling the entire array element, including the frequency selective surfaces and its feeding, into a single P C B plane. Importantly, the entire 3D printed structure was assembled with precision using standard PCB printed technology. Infinite array simulations showed a VSWR <2.8 at broadside with scanning capabilities down to 45° in all planes. To the author's knowledge this is the first ever realization of such large bandwidth mmWave arrays with wide scanning capability. The proposed concept was validated through fabrication and characterization of a 20 × 15 prototype in conjunction with finite array simulations.
