As C-ITS adoption accelerates, simulation tools are helping cities test and refine connected signal strategies without disrupting live traffic PTV Group (part of Umovity) – ITS European Congress Istanbul – Booth C4 Urban intersections remain one of the most critical bottlenecks in transport networks. As traffic volumes grow and mobility patterns become more complex, Cooperative Intelligent Transport Systems (C-ITS) have emerged as a promising technology with significant potential to improve traffic flow, safety and operational efficiency. An important tool for evaluating such connected strategies is microscopic traffic simulation. “Road space is limited, so it is all about using existing infrastructure in the most efficient way. C-ITS is becoming increasingly important for cities worldwide,” says Matthias Pfriem, senior product manager for PTV Vissim. “Simulation helps traffic planners and engineers create a realistic testing ground for intelligent signal control, allowing them to plan, test and optimise strategies before implementation.” Connected by design C-ITS enables real-time bidirectional communication between vehicles (V2V), infrastructure (V2I) and other road users. Connected vehicles transmit continuous data including position, speed, vehicle type and trajectory. For traffic control systems, this greatly expands the available information base and enables more adaptive and predictive signal control strategies. “Activating C-ITS in PTV Vissim simulations involves enabling V2I communication attributes within the simulation environment,” says Pfriem. “When those connected vehicle attributes are provided to a V2I-ready signal controller, that real-time information can be used directly in the signal control strategy for prioritisation of selected vehicles or for general optimisation of intersection performance. The simulation serves as a test-bed for exploring different control strategies in different traffic conditions and connectivity scenarios.” From data to dynamic control Within the simulation, vehicle data is transmitted to signal control logic, which dynamically adjusts signal phases. Planners can analyse how different penetration rates and demand conditions affect intersection