Digital Dichotomy: 5G or Wi-Fi? What is the future of vehicle-to-vehicle communication?

The automotive industry is trying to decide how cars will talk to each other.

Technology standards really matter when you pick the wrong one. Ask anyone whose wedding was recorded on a Betamax video cassette. Losing access to treasured memories because your uncle made a bad choice in the 1980s is annoying. Discovering that your self-driving car speaks a different language to the other traffic on the road could be fatal.

The mobility systems of the future will be increasingly reliant on technology, but the automotive sector has yet to agree on a fundamental issue: the way vehicles will communicate both with each other and with the wider world. Part of the industry is promoting a standard for vehicle-to-vehicle communication based on the Wi-Fi technology already used to connect electronic devices in homes and businesses around the world. Others support an alternative approach based on 5G mobile technology. Each side of the discussion is backed by major carmakers, as well as big-name players in the electronics and communications industries who are keen to capture a slice of a huge future market.

The technical arguments are complex, but a lot comes down to a balance of risks and opportunities. Proponents of Wi-Fi argue that their technology is reliable, available and well proven. Fans of 5G say that their approach is more powerful, flexible and futureproof. In April, the Wi-Fi side received a boost with backing from the European Commission, but in July, 21 EU member states voted against the proposal for a single European standard, clearing the way for 5G.

Who’s talking?

Part of the challenge is the wide range of communication tasks that future vehicles are expected to undertake. At the most local level, cars and trucks will speak to each other, indicating their current position and future intentions. Such vehicle-to-vehicle (V2V) communication should reduce collisions and smooth traffic flow. It will also enable new kinds of driving, for example allowing the “platooning” of trucks on highways, whereby a train of vehicles autonomously follows a leader with a human driver at the wheel. And it won’t just be vehicles in the conversation. Similar technology will allow cars to speak to road infrastructure, so that for example they receive an early indication from a pedestrian crossing that people are about to enter the road. V2V and some vehicle-to-infrastructure (V2I) communications will be short-range links made directly between the equipment involved. That makes communication fast – important for safety-critical decision-making – and it will ensure participants can still connect in places where mobile phone networks are poor, or when they break down. Other types of communication, however, will involve much longer distances. Vehicle-to-network (V2N) communication will be used for tasks such as the sharing of information on traffic conditions, the remote monitoring of vehicles by manufacturers or fleet owners, or the delivery of infotainment services to occupants.

According to the industry group 5G Automotive Association, its technology – unlike Wi-Fi – provides a solution for all those use cases. The same basic communication hardware will connect to the car in front, the internet via the nearest cell tower, or even the mobile phone in the pocket of the pedestrian who has stepped into the road just around the next blind corner. 5G networks will also be much smarter than earlier iterations. Powerful computers installed in cell towers will be able to take on complex, time-critical tasks, such as coordinating the flow of thousands of vehicles through a busy intersection or warning approaching traffic of an incident on the autobahn.

“Faster communications will be crucial for autonomous driving,” says Fathi Tlatli, President of the Global Auto-Mobility Sector at DHL. “These systems will need to be incredibly precise: Distances of one centimeter or delays of a fraction of a second could make the difference between a safe maneuver and a collision. At the same time, future vehicles will access and share an increasingly broad and complex range of data.” 5G technology, he adds, will help companies manage these new intelligent vehicles in a comprehensive way.

HIGH FIVE: 5G enables faster communications which is crucial for autonomous driving.

The future in production

From the end user’s point of view, all these amazing new capabilities are still some way off. Mobile operators are still building their 5G networks. Carmakers can buy the chipsets that will allow their vehicles to connect, but they still have to integrate them into new products. The really big mobility transformations, such as fully autonomous driving or smart connected traffic management systems, will take years or decades to develop.

In the meantime, 5G technology seems set to make its first breakthroughs not in cars and trucks, but in the factories that build them. Automotive supplier Robert Bosch is already an enthusiastic adopter of Industry 4.0 technologies. It is now installing private 5G networks in a number of factories around the world, aiming to use them to speed up and simplify the connections between smart production machines. Carmaker Audi, meanwhile, has a partnership with Ericsson to test 5Genabled automation systems at its factory in Gaimersheim, Germany

Applying 5G in the tightly controlled environment of the factory floor will help companies to refine their understanding of the technology before it is released onto the open road. It will also give the industry time to resolve its approach to communication standards. In the long term, today’s discussions will probably matter little to anyone outside the industry. Your phone switches seamlessly between Wi-Fi and cellular networks today. Tomorrow’s cars should be able to do the same. — Jonathan Ward

Published: November 2019


Images: Bosch; Friso Gentsch/dpa