Sub-THz Signal Distribution Based on Additively Manufactured Dielectric Image Lines

The realization of low-loss multi-channel power splitters at sub-THz frequencies is highly challenging, as conventional transmission-line-based approaches suffer from severe performance limitations, low scalability, or high fabrication costs. To illustrate an attractive solution to this problem, this work presents a broadband sub-THz signal distribution network based on additively manufactured dielectric image lines (DIL), enabling symmetric 1x6 power splitting across the 140–220 GHz range. For the first time, additive manufacturing (AM) is used to integrate various dielectric components like transmission lines, 1x2 and 1x4 splitters, a directional coupler with configurable power division ratio, and a dielectric termination into a large-scale, monolithic network. The concept is manufactured using up to four different AM techniques to investigate the impact of fabrication characteristics on network performance. Manufacturing artifacts are analyzed and modeled, revealing the impact of adhesion, surface quality, and process complexity onto key performance metrics like efficiency, bandwidth, port symmetry, and reproducibility.