±45° dual-slant polarized all-metal Vivaldi array with isosceles triangular lattice

This paper presents a ±45° dual-slant polarized all-metal Vivaldi antenna array with isosceles triangular lattice. To achieve grating-lobe-free operation over ±50° in the azimuth plane and ± 40° in the elevation plane, orthogonal Vivaldi radiators are rotated to obtain ± 45° polarization and arranged in an isosceles triangular lattice configuration. Extended tips of the Vivaldi radiators are employed to eliminate gaps between radiators and establish tight coupling among them, resulting in a wide impedance bandwidth within 5~18 GHz. Compared with traditional arrays based on a square lattice configuration rotated to achieve ±45° dual-slant polarization, the proposed array has a 39% larger cell size. The array can be modularly spliced, consisting of modular element radiators, SSMP fuzz button connectors, and a ground plane, which can be assembled and fastened using M2.5 stainless steel screws. Measured results of the fabricated 121-element antenna array are in good agreement with the simulations.