Hexagonal-Shaped Broadband Compact Scrimp Horn Antenna for Operation in $C$ -Band

The performance of compact linearly polarized Short Circular Ring-loaded horn with Minimized cross-Polarization (Scrimp) horns with different aperture sizes is first evaluated using an in-house finite-difference time-domain (FDTD) computer-aided design (CAD) tool. Then, a very short hexagonal Scrimp horn with an aperture size of 1.5λ₀ is designed in C -band; its height is only 1.26λ₀ . The experimental results demonstrate that the aperture efficiency is higher than 80% with a reflection coefficient lower than -17 dB over a 12.6% frequency bandwidth. Radiation patterns of excellent quality are measured with a cross-polarization level lower than - 28 dB over the entire bandwidth. These antennas are very attractive candidates for high-power focal array configurations in multifeed systems.