V2X Wiki

For those who are new to V2X, we put together some common jargon and their meanings in the world of V2X.


  1. Vehicle-to-Everything (V2X) communication aims to dramatically improve traffic safety and efficiency. Infrastructure and all road-users, including vehicles, trucks, motorcycles, and in the future pedestrians, securely exchange messages in order to indicate their location, speed, direction and other properties.
  2. Vehicle-to-Vehicle (V2V) communication connects vehicles to other vehicles for safety and mobility applications. US Department of Transportation estimated that 80% of unimpaired accidents can be avoided or their severity mitigated using this technology.
  3. Vehicle-to-Motorcycle (V2M) communication connects vehicles to motorcycles to reduce the high collision rate and fatalities in motorcycle accidents. About 1/3 of motorcycle accidents can be avoided with V2M.
  4. Vehicle-to-Pedestrian (V2P) communication connects vehicles to pedestrians. About 20% of road fatalities in US are pedestrians.
  5. Vehicle-to-Device (V2D) communication refers to the communication between vehicles and e-bikes, e-scooters, and other devices.
  6. V2X Evolution – V2X applications will be launched in phases, known as “Day1”, “Day2” and “Day3”. Day1 V2X offers basic driver awareness of surrounding vehicles. Day2 V2X applications can make use of sensor data shared by other vehicles for communicating information of non-connected road users, vehicles and pedestrians alike. Day3 V2X applications primarily provide the means for negotiations between vehicles for efficient and safer road usage. Applications in all phases can influence vehicle movement, with increasing influence as phases advance.
  7. Smart Intersection – An intersection that is equipped with a V2X system and one or more vision sensors, such as a camera. The camera identifies road-users, vehicles and pedestrian alike, as well as potential hazards and the V2X system shares this information with the drivers at the intersection. This use-case allows drivers to reap the benefits of their V2X system from Day 1 regardless if other vehicles in the intersection are connected.
  8. Dedicated Short Range Communication (DSRC)is a wireless communication technology specifically designed for automotive use that enables direct communication between vehicles and other road users, without involving cellular or other communication infrastructure.
  9. IEEE 802.11p is the underlying technology for DSRC (dedicated short-range communications). That’s one of the prevailing car-to-car or vehicle-to-infrastructure technologies used in Europe. Rooted in WiFi, it’s intended for non-associated data exchange in the 5.9 GHz band between potentially fast-moving vehicles.
  10. C-V2X (Cellular V2X) technology was introduced after DSRC, having the same purpose of direct communication link between vehicles. C-V2X is defined by 3GPP based on cellular modem technology, leading to fundamentally different non-interoperable access layer with DSRC.
  11. WLANp is also known as IEEE 802.11p
  12. V2N (Vehicle to Network) – As opposed to DSRC or C-V2X, LTE/5G for V2N operates in licensed cellular spectrum. This communication is good for Infotainment and non-mission critical, as it is non-secure, can’t assure continuous coverage, latency isn’t guaranteed, and can’t assure safety-critical network operation.
  13. 3GPP is the 3rd Generation Partnership Project. It is an organization which develops standards and protocols for the mobile industry.
  14. LTE stands for Long-Term Evolution. It is a standard for wireless broadband communication for mobile devices and data terminals, based on the GSM/EDGE and UMTS/HSPA technologies.
  15. PC5 is the underlying direct link cellular communication protocol of C-V2X.
  16. 9 GHz is the band allocated globally for V2X communication. Among the countries who have allocated spectrum for V2X in this band are: USA, Canada, Europe, Korea, China, Singapore, Australia and others.
  17. Road Side Units (RSU) are stationary V2X units. Infrastructure deployment projects are taking place around the world.
  18. Connected Vehicles are vehicles equipped with V2X system that can communicate with other vehicles, infrastructure and the “cloud”.
  19. Coordinated Manoeuvring is an application of V2X that will become available in “Day 3”. It refers to vehicles being able to coordinate between themselves in complex traffic situations such as lane-merge, roundabouts, 4 way-stop intersections and more.
  20. Cooperative perception allows vehicles to share objects detected by the vehicle’s onboard sensors such as cameras and radars. This enables drivers to get information about unconnected vehicles and road users.
  21. Situational Awareness refers to the V2X system giving the driver greater awareness of the on-road objects and potential hazards around.
  22. Left Turn Assistance – turning left can be a challenge in some right-hand traffic countries such as the US. It involves slowly moving into the middle of an intersection and then waiting for oncoming traffic to pass in order to turn safely. Many things can go wrong: overlooking oncoming traffic or the mis-estimation of oncoming vehicle’s speed. The left turn assist V2X Day1 application issues a warning to the driver or can automatically apply the brakes in order to avoid a collision.
  23. Vulnerable Road Users refers to all those road users and are less protected such as pedestrians, bicyclists, motorcyclists and more.
  24. Direct Communication is the basis of V2X. It is when vehicles relay messages to each other and RSUs directly and not through a network. Direct communication is the only form of communication that assures short-latency, coverage and reliability for life-saving safety applications.
  25. Platooning is when trucks drive in a convoy in order to save fuel by reducing drag. A feature that is enabled by V2X.
  26. Cooperative-Adaptive Cruise Control (CACC) allows vehicles to adjust their driving speed based on speed of other vehicles of lanes for setting the optimal speed avoiding collision resulted from late reaction to speed changes.