Vehicle-to-everything (V2X) is a technology that allows vehicles to communicate with moving parts of the traffic system around them.
Vehicle-to-everything (V2X) is a technology that allows vehicles to communicate with moving parts of the traffic system around them.
( Source: Adobe Stock)

V2X Beginners guide to V2X communication

Author / Editor: Cate Lawrance / Jochen Schwab

Part of our preparation for autonomous vehicles is the evolution of technologies that enable cars to communicate with each other and the infrastructure around them. Software, hardware, and firmware are being deployed in readiness for when we are only the passenger and cars, traffic control and other infrastructures create a seamless flow of journeys through our cities.

As we await the introduction of autonomous vehicles, we're also at work on the infrastructure that creates communication without the need for a driver or their input. One example of such infrastructure is communications between vehicles and the structures around them. This communication comes in two main components V2V and V2X (known collectively under the umbrella Vehicles to Everything (V2X):

Vehicle-to-Vehicle (V2V) Communication

Vehicle-to-vehicle (V2V) communication enables vehicles to wirelessly exchange information about their speed, location, and heading. Vehicles can broadcast and receive Omni-directional messages (up to 10 times per second), creating a 360-degree "awareness" of other cars in proximity. These messages can be used along with visual, audible and tactile alerts to warn the driver of potential road accidents or hazards ahead based on traffic, weather, and other factors.

An example of the software in action is HAAS alert. HAAS Alert makes roads and communities safer by delivering digital alerts from emergency response and other municipal fleets to nearby drivers via in-vehicle and navigation systems when emergency vehicles are approaching and on-scene.

Digital alerts are real-time notifications delivered to navigation apps on smartphones and in-vehicle navigation systems when responders and roadside workers are en-route or on-scene. Alerts are intended to notify motorists in advance to allow them more time to slow down, move over, and make safer decisions.

The Multi-Car Avoidance Project

In another example of V2V: In the UK, theMulti-Car Collision Avoidance Project (MuCCA) has been working to develop a next-generation driver aid that aims to avoid multi-car collisions on motorways. If an accident cannot be avoided, the MuCCA system will attempt to minimize its consequences (both injuries and damage).

Multi-Car Collision Avoidance Project (MuCCA)
Multi-Car Collision Avoidance Project (MuCCA)

During tests on a replica motorway, when the vehicles detect an incident, the cars share information by radio links, and the onboard computers calculate the best maneuvers to avoid the obstacles and then safely steer the agreed path to avoid an accident. The MuCCA equipped vehicles also avoid each other and remove the need to brake suddenly—which may have caused cars behind to drive into them.

Vehicle-to-infrastructure (V2I)

Vehicle-to-Infrastructure (V2I) communication is a wireless exchange of data between vehicles and road infrastructure. V2I communication is typically wireless and made possible via a combination of hardware, software, and firmware. A car may be communicating with road signs, cameras, traffic and other street lights, parking meters, and other infrastructure.

Similar to V2V, V2I employs dedicated short-range communication (DSRC) frequencies in the transmission of data.

Use cases include:

  • Pavement markings that are visible to humans and machines in any road condition and work with automated vehicle sensors to detect lines outside the vision-based spectrum, improving lane detection and traffic safety in even the most extreme weather conditions.
  • Integration with a central traffic control that identifies traffic bottlenecks and maps rerouting options
  • Real-time alerts of construction zones and other potential hazards.

Highly anticipated technology

In 1997, the Federal Communications Commission dedicated 45 MHz of spectrum in the 5.9 GHz band for future uses of V2V communication. The intention was to distribute 45 of the 75 MHz frequencies of the so-called "safety spectrum" for WiFi, with 30 MHz left for connected cars. Ford was last month lobbying the FCC not to reallocate this citing safety risks. As Axios notes "Interference from a WiFi signal that might keep children occupied with video games in the back seat could potentially delay the delivery of a basic safety message to their parent's car at precisely the moment it's needed."

Technology evolves fast in the V2V space

MUCCA offers an example of how fast V2X technology is evolving. When the MuCCA project started in 2017, there were two competing technologies for exchanging messages between vehicles. One was a version of WiFi that was specific for V2X (802.11p), and the other based on mobile telecommunications technology (Cellular Vehicle-to-Everything (C-V2X)). Now, a new generation of technologies is on the horizon: WiFi-based (802.11bd) and mobile telecommunications-based (New Radio V2X (NR-V2X) based on 5G. The area is evolving quickly, and many manufacturers have changed their allegiances.

Current commercial applications

CTS Sedan by Cadillac was the first car which uses Dedicated Short-Range Communications (DSRC) technology.
CTS Sedan by Cadillac was the first car which uses Dedicated Short-Range Communications (DSRC) technology.

Cadillac was the first company to introduce V2V in the CTS sedan in 2017, which uses Dedicated Short-Range Communications (DSRC) technology. It's now extended its functionality to include V2X meaning compatible vehicles can be notified of hazardous road conditions, traffic light statuses, changing work zones and more. With a range of nearly 1,000 feet, drivers can be alerted to possible threats in time to avoid a crash.

Cadillac plans to offer V2X communications in a high-volume crossover by 2023 and eventually expand the technology across Cadillac's portfolio.

While some are waiting for 5G to become more widely available, VW has opted for wireless standard WLANp, specially designed for local vehicle communication and real-time data transmission. Based on radio communication without the need for WiFi, the signal can reach 150 meters in the city and up to 800 meters on rural roads and highways.

Car2x interconnects vehicles, infrastructure and traffic control centers.
Car2x interconnects vehicles, infrastructure and traffic control centers.
(Source: Siemens)

Siemens has been working on deploying their existing V2V infrastructure (currently being tested by the NYC Department of Defence) to encompass rail, ship and airplane communications in the future.

V2X payments are coming

One of the many exciting ideas under development is a market place for V2V and V2I communications, creating a seamless payment system between vehicles and other infrastructure. One company working in the space is IOTA which uses blockchain technology to enable trusted connectivity and micropayments. An example in the future might be a car paying a fee to another to overtake them during peak hour.