This work focuses on the impact of the build orientation on additively manufactured waveguide-based hybrid couplers for D-band frequency range and relates it to other sources of uncertainty within the overall manufacturing process and measurement instrumentation for the D-band frequency range. The designed specimens are first printed from UV curable photopolymer resin and subsequently metal coated by an electroless silver plating process, which in turn is improved by making use of the slotted waveguide approach. Although the requirements toward geometrical precision to achieve phase errors below 10° are in an order of 0.1 mm, a desktop grade DLP printer is utilized in this work in order to point out the prospects and limitations of additive manufacturing. Furthermore, waveguide paths with bends are part of the model and their impact on the measured attenuation is estimated explicitly.Despite this narrow field of tolerances, one specimen could have been realized, which achieves a measured output magnitude imbalance of 0.7 dB over the frequency range from 120 to 155 GHz while at the same time exhibiting a phase deviation of only <10° from the desired 90°. With these demonstrated results, the proposed approach provides suitability for future applications in the D-band frequency range.

中文翻译：

---

用于 D 波段应用的 3D 打印混合耦合器的设计和分析

这项工作的重点是构建方向对 D 波段频率范围内增材制造的基于波导的混合耦合器的影响，并将其与整个制造过程中的其他不确定性来源和 D 波段频率范围的测量仪器联系起来。设计的样品首先由紫外光固化光聚合物树脂印刷，然后通过化学镀银工艺进行金属涂层，然后通过使用开槽波导方法进行改进。尽管实现低于 10° 的相位误差对几何精度的要求约为 0.1 毫米，但在这项工作中使用了桌面级 DLP 打印机，以指出增材制造的前景和局限性。此外，带有弯曲的波导路径是模型的一部分，它们对测量衰减的影响被明确估计。尽管公差范围很窄，但可以实现一个样本，在 120 的频率范围内实现 0.7 dB 的测量输出幅度不平衡至 155 GHz，同时与所需的 90° 相差仅 <10°。有了这些证明的结果，所提出的方法为 D 波段频率范围内的未来应用提供了适用性。