A Low-profile Dual-polarized Ultra-wideband Metal Antenna Array

A dual-polarized ultra-wideband phased array composed of low-profile metal antennas is presented. The design allows for practical implementation of the tightly coupled dipole arrays (TCDAs) at VHF-UHF frequencies. Integrated metal dipole and Marchand balun are designed to ensure the antenna structure's robustness. The dipole consists of vertical and planar components, resulting in a low profile and good impedance matching. The antenna array exhibits an operational bandwidth of 4.6:1 for ±45° scanning in all planes, maintaining active VSWR < 3. Orthogonal port isolation remains below -26 dB when scanning in E-/H-planes. The element spacing and profile of the array are 0.535λh and 0.44λh (λh refers to the wavelength at the highest operating frequency in free space), respectively.