Update Rate and Dimension Requirements for Reconfigurable Mirror Arrays in Vehicular Visible Light Communication

For Visible Light Communication (VLC) between vehicles, maintaining Line of Sight (LoS) is a fundamental requirement. Especially when a sequentially communicating convoy (platoon) is turning at an intersection within a city, the direct line-of-sight connection can be interrupted, leading to a disruption of VLC communication. Particularly in urban locations with obstructed view, it is crucial for future autonomous driving to convey critical information, such as crossing pedestrians and other obstacles like partial road closures due to construction sites, to following vehicles. Within the development of Sixth-Generation (6G) wireless networks, the use of Reconfigurable Intelligent Surfaces (RIS) is proposed as one option to address the LoS issue. In this work, a conceivable use case is investigated to examine through ray-optical simulations the requirements for the update rate of such systems when RIS elements are reconfigured discontinuously. Additionally, the influence of the size of the device surface area on the resulting signal strength in the described traffic situation is provided. The findings suggest that delays in updating array elements significantly impact situations where the transmitter is far from the intersection, offering crucial insights for autonomous driving system development.