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

This article details the design and manufacturing process of a compact module fed through a transition between a grounded coplanar waveguide (GCPW) input line and an air-filled (AF) waveguide integrated into the substrate. This waveguide feeds a micromachined horn antenna. The developed technology is based on the micromachining of an AF 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. The novelty of this work relies in the use of this innovative technological process for the realization of millimeter-wave (mm-wave) subsystems. Furthermore, the developed technology enables the creation of high-performance components utilizing AF substrate integrated waveguides (AF-SIWs). 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 mm-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.