Challenges and Future Research Trends of Window Glass for Smart Rail Vehicles: From the Perspective of Wireless Propagation

Emerging window glass plays an increasingly important role in rail vehicles thanks to its outstanding mechanical, optical, and thermal performance. However, due to insufficient attention on the electromagnetic (EM) properties and wireless propagation characteristics, the potential of window glass to enhance the intelligence of rail vehicles and the wireless communication of onboard passengers is not fully realized. To a certain extent, window glass even becomes the bottleneck of the informatization of rail vehicles. Thus, this article aims to explore window glass for one important component of vehicular networking-smart rail vehicles-from the perspective of wireless propagation. In this context, we present key capabilities and discuss the potential forms of window glass for smart rail vehicles. Finally, based on the review of representative research, we investigate and outline the future research challenges and trends from the propagation channel perspective.