Empirical Analysis of using Public Transport Vehicles as Urban V2X Infrastructure

Vehicle-to-Everything (V2X) communication is a critical enabler of intelligent transportation systems, supporting real-time data exchange for improved safety, efficiency, and automation. However, existing offloading approaches, based primarily on static roadside units (RSUs) and unmanned aerial vehicles (UAVs), face limitations in cost, scalability, and adaptability to dynamic traffic conditions. As 6G networks begin to take shape, the demand for more flexible, scalable, and cost-effective infrastructure is increasing, calling for novel solutions. One promising direction is the use of public transport vehicles as mobile RSUs (mRSUs), leveraging their predictable routes, consistent presence in traffic, and capacity to host dedicated communication hardware.This paper presents an empirical analysis of the availability of public transport vehicles using real-world positioning data collected in Bratislava on both workdays and weekends. By generating spatial heat maps and minute-level density plots, we evaluated the feasibility of using buses, trolleybuses, and trams for IEEE 802.11p-based V2X offloading. The results indicate that these fleets offer sufficient temporal and spatial coverage to complement existing RSU and UAV infrastructure. Our findings provide practical insights for the integration of public transport into future V2X systems, highlighting a scalable and cost-effective strategy for the deployment of smart cities.