Printed Circuit Board (PCB)-Integrated Millimeter Module Composed of a Horn Antenna Fed Through a Grounded Coplanar Waveguide

This paper details the design and manufacturing process of a compact module fed through a transition between a grounded coplanar waveguide input line and an air-filled waveguide integrated into the substrate. This waveguide feeds a micro-machined horn antenna. The developed technology is based on the micromachining of an air-filled waveguide on a first substrate and a horn antenna on a second one. These two substrates are then assembled by a thermal diffusion process, which allows for creating an electrically conductive bonding interface. Novelty of this work relies in the use of this innovative technological process for the realization of millimeter-wave sub-systems. Furthermore, the developed technology enables the creation of high-performance components utilizing air-filled substrate integrated waveguides (SIW). This approach effectively addresses the challenges associated with transferring, integrating, and reducing costs often encountered in high-frequency systems development. The resulting device forms a highly integrated, low-cost, yet electrically performant millimeter-wave module entirely manufactured with a Printed Circuit Board (PCB) process. The manufactured prototype operates at V-band, exhibiting a bandwidth of 3.1% and a maximum gain of 6.4 dBi.