Design, Realization and Screwless Assembly of a Hybrid PCB-Waveguide Module Using Additive Manufacturing

This paper presents the study, design, realization, and measurement of a hybrid module integrating printed circuit board (PCB) and waveguide structures. The proposed approach leverages the advantages of both technologies: the compact integration and cost-effectiveness of PCB-based circuits combined with the high electrical performance of waveguides. Waveguides structures were fabricated by using metallized plastic additive manufacturing, enabling complex geometries while maintaining low mass and costs. Detailed synthesis of two transitions between PCB and waveguide sections is provided, addressing impedance matching, mode conversion, and fabrication constraints. A careful attention was brought to the mechanical and mass aspects of the assembly to account for highly demanding environments, thus avoiding any screws in the fabrication process. The module is then designed and optimized through full-wave electromagnetic simulations, followed by prototype fabrication and experimental validation. Measured results demonstrate good electrical performances, confirming the relevancy of the proposed integration strategy. This work contributes to the development of efficient, compact and lightweight RF front-end modules for emerging microwave and millimeter-wave applications.