An Omni-Directional Horizontally Polarized Antenna for 18-40 GHz Site VSWR

This paper presents the design and demonstration of an Omni-Directional Horizontally Polarized Antenna. Classified as a “loop” or “magnetic dipole” antenna, it exhibits an ultra-wide bandwidth of 18 to 40 GHz. The antenna has a 50 mm diameter, is constructed on a PCB substrate and maintains a dipole-like radiation pattern across the entire frequency range. Notably, it demonstrates H-Plane symmetry with a deviation of less than <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\pm 1.5 \text{dB}$</tex>. Chamber validation has been successfully conducted, utilizing the cylindrical mode filter technique to prove the antennas performance.