An Additively-Manufactured, Internally Metalized FUSETM(IM-FUSE) Array

In this paper, a new design technique is introduced which improves performance and lowers the fabrication cost of the Frequency-Scaled Ultra-Wideband Spectrum Element (FUSE™) aperture. The additively manufactured (AM) geometry is designed as a single block of polymer with hollow interior cavities corresponding to the radiating element shapes. An electroplating process is used to metalize only the interior surfaces of the cavities, enabling electrically isolated radiators with strong inter-element capacitive coupling. This technique results in a robust mechanical structure, eliminates the need for coaxial interposers, and utilizes low-cost plug-in connectors. The resulting simulated dual- polarized array achieves an active VSWR of 3.2:1 or less over a 7.3:1 frequency bandwidth while scanning to 60° in in the E, H, and D scan planes with high Cross-Polarization Gain Isolation over most of the band.