When we talk about the future of the automotive industry, most people are talking about self-driving cars. But it’s not just the cars that are getting smarter. City infrastructure itself is advancing in leaps and bounds. “Vehicle-to-infrastructure” or V2I technology will allow cars to communicate with elements of the roadway for a future that’s optimally safe, efficient, and badass.

There are already cars on the road talking with traffic lights. And if your car can’t do it, there’s an app for that. V2I technology is an inevitable future. The only question is how we get there, and with which competing system.

What Defines V2I Technology?

Vehicle-to-infrastructure technology opens up a line of communication between a car and its environment. Previously, V2I mostly focused on making infrastructure better at recognizing what’s going on with people and vehicles. For example, it’s vehicle-to-infrastructure communication when you pull up to an empty intersection and the light detects your presence and turns from red to green.

Today’s V2I is focused on taking the mystery out of signal changes for drivers. Auto manufacturers are making vehicles that display signal timing information right in a car’s dashboard. If the driver is approaching a green light, the V2I display will tell the driver whether the light will remain green. The driver won’t need to accelerate in an effort to get through the intersection before the light changes. And if they know for sure they won’t be able to make the light, they can gradually slow their speed. This prevents the bursts of acceleration and then deceleration that come when drivers attempt to make a light they’re doomed to miss.

The display will also tell drivers when the red light they’re sitting at will change to green.  Everyone’s been the distracted driver who doesn’t notice when the light turns. Many of us have even been the jerk behind him honking the horn. A V2I in-dash system will help drivers stay alert and keep traffic moving. It might even save lives.

Benefits of Vehicle-to-Infrastructure

In 2013, California’s Los Angeles County synchronized all its 4,500 traffic lights over 469 square miles. They’re the first municipal area to do so worldwide. A Texas A&M report says Los Angeles is saving $1.3 billion in fuel and time every year. The Scientific American breaks that down into annual savings of 31.3 million hours of travel time, 38 million gallons of fuel, and 337,000 metric tons of carbon dioxide. That’s just traffic lights. Imagine if the cars were also in sync.

The potential fuel savings of vehicle-to-infrastructure communication are tremendous. V2I technologists speculate that if this system is implemented widely enough it will move the needle on global warming. A January 2016 study from Washington, D.C.’s Transportation Research Board confirms this belief. The paper predicts fuel savings of up to 56 percent with a properly implemented V2I system.

It’s also a great deal safer, especially when combined with “vehicle-to-vehicle” communication. The US Department of Transportation estimates that 80 percent of all unimpaired vehicle crashes would be prevented with V2I and V2V technology. Rear-end collisions are the most common type of auto accident and there are 2.5 million of them every year. These are particularly common at signalized intersections, one of the most dangerous places on the roadway. If drivers were aware of signal changes, unexpected starts and stops would be reduced. So would the number of fender-benders, bumper-bumpings, and mid-intersection T-bones.

V2I will help usher in a safer, swifter, and more efficient future. It might sound like a sci-fi dream but, like driverless cars, V2I isn’t just close. It’s here.

Audi Takes the Industry Lead in V2I

Audi made headlines for V2I last month. On August 15, Audi announced it’s going to produce cars that can “talk” to traffic lights. Its in-dash navigation will display traffic signal information including how long many seconds an upcoming light will remain green and when a red light will change. This feature will be available on certain 2017 models produced after June 2016.

"This feature represents Audi’s first step in vehicle-to-infrastructure integration," said Pom Malhotra, general manager for Audi’s connected vehicles division. "In the future we could envision this technology integrated into vehicle navigation, start/stop functionality, and can even be used to help improve traffic flow in municipalities. These improvements could lead to better overall efficiency and shorter commuting times."

Like other V2I platforms, this new Audi feature is only available in limited cities. Malhotra projected five to seven urban areas will be on line by the end of the year. It also isn’t free. Drivers must choose to purchase Audi’s Connect Prime infotainment package (at $199 for 6 months or $750 for 30 months).

Audi is being widely lauded as the first car company to make vehicles that display traffic signal information. But V2I has been in the works and on the books for some time. BMW introduced in-dash V2I technology in July 2015 in partnership with the startup Connected Signals. Connected Signals released a phone app called EnLighten on the same day BMW announced its integration of the feature.

BMWs equipped with EnLighten operate similarly to the new Audis. An in-dash operation panel displays information regarding when and whether the light ahead will change. The EnLighten phone app does exactly the same thing on your mobile device. The app is free. Anyone with an iPhone can get the same V2I info that’s available in new, high-tech cars. 

Connected Signals gets live data from over 100 US towns and cities. But like the new Audis, their geographic penetration is very limited. Cities where EnLighten and connected BMWs work right now include:

  • Portland and Eugene, Oregon
  • Garland, Texas
  • Most of Utah
  • Las Vegas, Nevada
  • Walnut Creek and Arcadia, California

Everyone involved with V2I is working constantly to expand its reach. But before we can expect accurate signal data in every dashboard across America, the industry is going to have to make a choice. There are two different ways for cars to access signal information. The choice between them defines the real battleground of V2I.

Direct Short Range Communications (DRSC) vs. Cellular

There are two ways vehicles can communicate with traffic lights: Direct Short Range Communications (DSRC) and cellular. These two technologies look the same for the user, but they work through very different mechanisms.

Direct Short Range Communications is a kind of transmission that comes directly from the traffic signal itself, like Wi-Fi or radio. A car is equipped with its own DSRC radio, and the two radios can pass information between each other when they’re in range.

DSRC was first considered for V2I decades ago as a way to simplify road toll collection. When people realized they could put DSRC radios on traffic lights, it was obvious this technology could improve traffic safety and congestion. In 1999, the Federal Communications Commission designated the 5.9 GHz band of the radio spectrum for the exclusive use of DSRC. The federal government has been committed to DSRC as the future of V2I technology since.

Enter cellular. When everyone first threw their weight behind DSRC, their cell phones could barely send texts. Today almost every driver has a smartphone in his or her pocket. Those phones have access to Wi-Fi and GPS. And every major American city has a traffic signal system that’s online.

Cellular allows drivers to access information about the infrastructure through the internet. This is how Audi and BMW are currently doing it. Matt Ginsberg, the CEO of Connected Signals and the EnLighten app, explains this process:

“All the traffic lights typically talk to a central location. The reason they do that is so that the central location can keep them synchronized. The clocks in the individual traffic lights are eventually going to drift, so something has to keep them agreeing as to what time of day it is. That’s why they talk to a central system. Each city has one that is connected to the internet in some way. That central system can just decide it wants to take the information it’s getting from the traffic lights about what they're doing and push it out to a third party…

“That goes over cellular. In some cases, it goes to the driver’s cell phone. For fancy cars like Teslas, you can actually communicate directly with the car. The car actually has a phone number. Audi is just starting to make cars that have this embedded telephone.”

Companies like Connected Signals are changing the V2I equation. DSRC radios are truly “vehicle-to-infrastructure.” The car and the traffic light are beaming radio waves right into each other’s transmitters from a close range. With cellular technology, it’s more like “vehicle-to-database-to-infrastructure” communication. Some third party sends a city’s grid information to drivers using satellites thousands of miles away.

The countdown to a red light will look the same in your dashboard whether it’s coming from the signal’s DSRC radio or the traffic control center’s timing data. But the differences in terms of cost and safety are gigantic.

Comprehensive DSRC Will Cost Billions

The federal government has invested millions in funding DSRC test sites. But traffic isn’t controlled federally. It’s controlled locally. And municipalities have been more eager to adopt cellular V2I than buy the hardware necessary for a DSRC system.

“DSRC made sense back before everyone had cellphones,” says Ginsberg, “but now that all the infrastructure is there—the lights can communicate with the centers, the centers communicate with the internet, the cellular works to communicate with the phones—there really is in general no reason to build this infrastructure over again. The cost of putting in DSRC radios is billions, and we can do it all essentially for free.”

And when it isn’t free, it’s cheap. Ginsberg says most large cities already have systems that can push their data to a third party. If a city is too small to afford this software, Ginsberg says Connected Signals will just give them a piece of hardware that does the same thing.

“I’ll go into a city, hand them a box, and say, ‘Plug this box in, and it’ll push your traffic light data out to us.’ And that’s all we need,” he says. These boxes cost Connected Signals about $80 each. This single, inexpensive device will get a whole city’s traffic signal data into the hands of drivers.

Conversely, a single DSRC radio costs $1,100 to $2,200. It also requires installation, maintenance, and replacement. And DSRC radios on traffic lights won’t be helpful unless we have DSRC radios in all our cars. Installing a DSRC radio in your vehicle costs somewhere between $4,150 and $9,200.

“The government, as I’m sure you know, does not change its mind quickly,” says Ginsberg. “But I think it’s starting to change its mind. When we started this a few years ago I’d go to the Feds and I’d say ‘We’re doing it this way,’ and they’d say, ‘No, no, no, DSRC.’ And I’d say, ‘But DSRC has been around for a decade, nobody has the money to adopt it, and this is free.’ There are still plenty of people in the government who are still committed to that, but now there are people I talk to in the government who, when I tell them we can do this for basically nothing, their eyes light up. Nobody’s got a few million bucks to spare to put DSRC radios everywhere.”

It seems that even when cities are willing to throw major dollars at infrastructure they still aren’t going for DSRC. For example, Seattle is in the process of pouring a $13 million levy into methods that alleviate traffic congestion. In July 2016, the city invested $651,000 of that in Siemens’ Concert software system with some of that levy. Concert allows for adaptive signal timing and V2I communication. Through cellular, that is.

“Concert does not have the capability to communicate directly with individual vehicles,” says a representative for the Seattle Department of Transportation, “but it does allow SDOT to provide our signal timing data to a third party via our data Seattle portal. Providing the data to a third party will allow vehicle companies to integrate this data within the vehicle. The data project will be worked on in 2017, with targeted availability end of 2017.”

It seems car manufacturers are also leaning toward cellular for V2I. In addition to its partnership with BMW, Connected Signals has announced partnerships with Toyota and Nissan. It’s also in conversation with six other unannounced automakers. Audi partnered with one of Connected Signal’s competitors for its cellular platform, and though they say they’ll incorporate DSRC as it becomes available, cellular was enough for them to roll out.

Cellular has accelerated the feasibility of V2I. But don’t write off DSRC yet—there are some reasons it might be worth the price tag.

What DSRC Can Do That Cellular Can’t

The most exciting thing about V2I isn’t getting signal-timing data in your car. It’s the possibility that all cars on the road could be connected and in communication with both the infrastructure and each other. DSRC allows for both V2I and V2V communication. And though cellular data can save drivers time, it’s DSRC data that can save lives.

DSRC can communicate much more information than cellular and do it more accurately. DSRC can transmit a vehicle’s latitude, longitude, heading angle, speed, throttle position, brake status, steering angle, headlight status, turn signals, and more. With this, one can calculate whether or not cars are on collisions courses. It would allow driverless vehicles to safely navigate the roadway. It would help cars with human drivers avoid some fatal human error.

The fact that DSRC radios have a spectrum specifically designated for vehicles is another huge advantage. There is less chance of data breaches or interference. It’s also faster—the latency is estimated at about 10 milliseconds.

Further, cellular-based apps only work with timed signals. Sensitive signals that aren’t controlled by the grid but change according to the presence of a vehicle wouldn’t push data to the app.

Dave Miller, head of connected vehicle efforts within Siemen’s intelligent traffic systems business, understands the advantages of both DSRC and cellular. He believes the future of V2I will combine both technologies.

“DSRC is used in safety systems where vehicle locations, directions, and speeds must be sent, received and authenticated within 100 meters in order to warn drivers on crash courses,” says Miller. “USDOT studies indicate that 81 percent of non-distracted crashes will be avoided using V2V and V2I, to the point of mandating the technology as a safety device on new cars, similar to seat belts and air bags.”

Miller predicts that “DSRC will be a standard safety device on new vehicles and a popular aftermarket device added to existing vehicles for crash avoidance.” But he also believes cellular data will remain useful in low-budget, low-stakes situations.

“Cellular provides a low-cost solution for mobility applications that can stand delays and outages without introducing safety issues,” he says. “[It can be] used in mobility systems where the data can be older or intermittent. For example, the signal countdown received by Audi may be one or two seconds old. Cars will collide before the warning reaches each car, so the data is not used for crash avoidance. But the cellular data is used to provide the driver with speed advice to catch the green light, which reduces stops by 15 percent to 20 percent along with reduced fuel and pollution.”

It’s possible that the accuracy of GPS technology could improve to the point of utility for V2V and crash avoidance. But even Ginsberg believes that even then, the future of V2I will combine DSRC and cellular.

“At the end of the day our technology and DSRC aren’t really competitors,” he says, “because there are lots of lights that are never going to be connected to a central system.” For example, a cellular app would never catch a lone traffic light in the middle of Wyoming. A DSRC radio would. And someday a driverless car in the middle of Wyoming will know exactly how many seconds it has to make the light.