3D Rapid-Prototyped 21-31-GHz Hollow SIWs for Low-Cost 5G IoT and Robotic Applications

This article presents, for the first time, new design and fabrication techniques for Hollow Substrate Integrated Waveguides (HSIWs), demonstrated in the nominal frequency from 21 to 31 GHz, for use in wireless communication applications such as 5G, IoT and robotics. The design and fabrication techniques introduced in this paper feature: 1) the use of low-cost rapid prototyping additive manufacturing based on polymer jetting (PJ), and 2) the use of commercially available through-substrate copper via transitions. In contrast to the conventional SIW designs and fabrications, this new approach does not rely on through-substrate via fabrication, hence avoiding some difficult manufacturing steps, such as through-substrate etching, via formation and via metallization, which are considered complex and expensive to implement. The 3D printed HSIWs in this article can achieve a propagation loss of lower than 1.56 Np/m (13.55 dB/m), which is considered one of the results with the lowest propagation loss achieved to date, when compared to the state-of-the-art.