Single-Polarization Vivaldi Antenna Array with Orthogonal Walls for Improved Polarization Purity

Linearly polarized arrays of Vivaldi antennas are a common choice for ultra-wideband aperture implementations, often with a focus solely on bandwidth needs and less attention to polarization purity. With some forethought, it is possible to design Vivaldi antennas for low cross-polarization levels. In this paper, we highlight a simple approach to mitigate cross-polarization in two-dimensional array apertures of linearly-polarized Vivaldi antennas. This is demonstrated through a direct manufacturing approach that creates orthogonal metallic cross walls in arrays of all-metal linear Vivaldi flares. This demonstration has notable utility, as unlike dual-linear Vivaldi arrays, calibration of amplitude/phase via orthogonal channels cannot be used to correct polarization at a given frequency/angle in single-polarization Vivaldi arrays, as there are no orthogonal elements.