Vehicle Communication

Vehicle communication is a technology that enables vehicles to continuously exchange data with each other and their surroundings in modern transportation systems. This system has been developed to enhance road safety, improve driving experience, and lay the foundation for autonomous vehicle technologies. Known in English literature as “Vehicle Communication,” this concept enables faster, more efficient, and safer traffic management especially in urban and highway environments.

This communication system allows vehicles to exchange data in real time with traffic signs, traffic lights, pedestrian crossings, other vehicles, and infrastructure components. For example, the location of a vehicle involved in a collision at an intersection can be instantly transmitted to other vehicles, preventing potential new accidents. Alternatively, the position of an ambulance can be communicated to all vehicles on the road to ensure priority passage.

The foundation of this technology lies in standards and protocols that enable wireless, rapid, and secure data exchange. Among the most common communication technologies are IEEE 802.11p and C-V2X. Thanks to these technologies, vehicles can share critical information such as real-time position, speed, direction, and braking status, enabling them to make decisions almost independently of the driver.

Vehicle Communication Technologies

V2X (Vehicle-to-Everything) is an overarching term that enables vehicles to communicate with all other systems. Under this umbrella, four main communication types are defined: V2V (Vehicle-to-Vehicle), V2I (Vehicle-to-Infrastructure), V2P (Vehicle-to-Pedestrian), and V2N (Vehicle-to-Network).

V2V communication refers to direct communication between two or more vehicles. This system allows vehicles to monitor each other in terms of speed, direction, and braking status, playing a significant role in accident prevention. V2V technology is particularly vital in situations such as lane changing, intersection crossing, and sudden braking.

V2I communication denotes data exchange between vehicles and infrastructure components such as traffic lights, intelligent signage, and road sensors. For instance, a vehicle approaching a red light can receive a warning if it is at risk of running the light, or it can be informed in advance how much time remains before the light turns green.

V2P enables communication between vehicles and pedestrians. Especially at intersections or school crossings, communication between pedestrians’ mobile devices and vehicles helps ensure safe passage. This technology can also provide convenience for people with disabilities.

Finally, V2N communication allows vehicles to exchange data with cloud systems via the internet. Through this system, information such as weather conditions, traffic congestion, and accident reports is transmitted to vehicles from centralized data centers. Together, all these components work in an integrated manner to create a smarter transportation infrastructure.

Standards in Use: IEEE 802.11p and C-V2X

The two most widely used standards in vehicle communication systems are IEEE 802.11p and C-V2X. IEEE 802.11p is a modified version of traditional Wi-Fi technology, specifically developed for vehicle-to-vehicle and vehicle-to-infrastructure communication. This technology is preferred in time-critical applications due to its low latency.

C-V2X (Cellular Vehicle-to-Everything) is a standard based on cellular communication infrastructure. Leveraging LTE and 5G technologies, it offers longer range, lower latency, and higher data rates. C-V2X encompasses not only direct vehicle-to-vehicle communication but also connectivity with base stations and cloud servers.

While IEEE 802.11p offers the advantage of independent operability, C-V2X provides a more comprehensive data exchange environment through support from cellular infrastructure. The comparison between these two technologies should be based on the specific application scenario, and system design must be tailored accordingly.

Technologies and Standards in Use

The two most widely used standards in vehicle communication systems are IEEE 802.11p and C-V2X. IEEE 802.11p is a modified version of traditional Wi-Fi technology, specifically developed for vehicle-to-vehicle and vehicle-to-infrastructure communication. This technology is preferred in time-critical applications due to its low latency.

C-V2X (Cellular Vehicle-to-Everything) is a standard based on cellular communication infrastructure. Leveraging LTE and 5G technologies, it offers longer range, lower latency, and higher data rates. C-V2X encompasses not only direct vehicle-to-vehicle communication but also connectivity with base stations and cloud servers.

While IEEE 802.11p offers the advantage of independent operability, C-V2X provides a more comprehensive data exchange environment through support from cellular infrastructure. The comparison between these two technologies should be based on the specific application scenario, and system design must be tailored accordingly.

Security and Privacy

Security and privacy principles are of great importance for the effective operation of vehicle communication systems. Since the data exchanged between vehicles includes sensitive information such as driver identities, locations, and travel patterns, unauthorized access to this data could lead to serious consequences.

Therefore, strong authentication mechanisms, end-to-end data encryption, and secure protocol management must be implemented. The source of every message must be verifiable, and unauthorized access must be prevented. Additionally, digital signature systems should be used to prevent the dissemination of fake messages.

Vehicle Communication Research in Türkiye

Research efforts in Türkiye are primarily conducted through academic projects and university-industry collaborations. At Galatasaray University, a system using the IEEE 802.11p protocol has been developed to enable low-latency communication between vehicles, integrated with camera-based vehicle tracking.

This study is one of the rare examples in the country where vehicle communication systems have been theoretically examined and supported by practical testing. Additionally, TUBİTAK-supported projects aim to develop a local 5G-based V2X infrastructure.

Future Perspective

Vehicle communication is shaping not only today’s driver assistance systems but also future autonomous transportation systems. For fully autonomous vehicles to operate safely, V2X technologies must be widely adopted. Through these communication systems, vehicles will continuously receive data from their surroundings to determine the most optimal driving strategies.

Moreover, these systems will contribute to smart city infrastructure. For example, applications such as adjusting traffic lights based on congestion levels, creating automatic green waves for ambulances, and reducing traffic density by monitoring air pollution levels become feasible.