Imagine driving down a city street. The traffic light ahead senses the speed of your approach and stays green for your benefit. Then imagine that the same traffic light sends you a message to keep your speed at 34 mph and you will have green lights at every intersection. The result is time and fuel saved plus reduced vehicle emissions.

Perhaps you are driving on a curving road and around the bend, out of sight, a stalled car sits in your lane. Your dashboard lights up with a warning and the automatic emergency braking on your truck kicks in, preventing a rear-end collision. Result: improved safety.

These are just some of the scenarios that the next level of vehicle technology will address. That technology is V2X – vehicle-to-everything. V2X combines the technological subsets of V2I – vehicle-to-infrastructure — and V2V – vehicle-to-vehicle.

The traffic light example relies on V2I, where infrastructure equipped with sensors and communication capability adjusts for road users and informs them of safe and efficient operations. In the V2V example, a technology-equipped car and similarly-equipped truck “talk” to each other.

Science fiction? No. V2X is already here. Some Japanese and European car makers and several high-end American luxury brands build the technology into their vehicles. And safety researchers have had, for many years, real-world projects in places where urban infrastructure and a wide range of vehicle types are fitted with V2X technology, testing its benefits and limitations.

How did this technology come about?

See this chronology:

  • In 1999, the Federal Communications Commission (FCC) reserved the entire 9 GHz spectrum for communications to improve highway safety.
  • In the past two decades, much of the research and testing utilized direct short-range communications (DSRC) technology.
  • In November 2020 the FCC announced that it was reallocating the lower 45 megahertz (5.850-5.895 GHz) of the 5.9 GHz “Safety Spectrum” to unlicensed uses like Wi-Fi. The remaining 30 megahertz (5.895-5.925 GHz) would continue as the home for vehicular safety.
  • In April 2023, the FCC determined that DSRC had not sufficiently penetrated the vehicle market and that, where deployed, DSRC technology should be discontinued. Instead, FCC gave the go-ahead to cellular technology (C-V2X) as the basis for highway safety, again utilizing the upper 30 megahertz of the 5.9 GHz spectrum.

The approval of cellular technology means that safety will no longer be dependent on line-of-sight, a limitation that plagues cameras, radar and DSRC. Instead, a vehicle equipped with C-V2X will send a “basic safety message” to all others within range, saying “here I am, here is the direction I’m headed, and here is the speed, or the hard braking, of my travel.” Vehicles receiving that “basic safety message” can automatically adjust to avoid collisions.

Sound like the advent of autonomous vehicles? Yes. That is one goal envisioned. While some vehicles will automatically avoid each other, many drivers will receive warnings and information that should improve safety. And that includes trucks, too, even those not yet equipped with C-V2X. Smart intersections, after all, will gather input from roadside readers and adjust traffic controls for the safety and efficiency of all.

The PrePass blog and podcasts are published as a public service of PrePass®, the most reliable and technologically advanced weigh station bypass and integrated electronic trucking toll payment platform in North America. PrePass also includes INFORM™ Safety and INFORM™ Tolling software for improving truck safety scores and lowering toll costs.