Ultra-wideband will turn your phone into a car key

Published in Stacy on IoT on May 2, 2023.

Are you ready to dump your car keys? To ditch the fobs, which have largely replaced physical keys, for your smartphone? Even if you’re not, the technology is coming, and with it, potentially other new features, such as the ability to detect children left in car seats.

At the end of March, a group of automotive and smartphone companies got together at a Google office to test out the Car Connectivity Consortium’s (CCC’s) Digital Key. The goal of the plugfest was to test out how well different phones and cars worked together to unlock and start vehicles using only a smartphone. Participants included Apple, BMW, Continental Automotive, Google, OPPO, Rivian Automotive, and Samsung.

This particular testing effort gets us closer to what has been a 5-year plan to use some kind of radio frequency technology to let users open and start their cars using only their smartphones. And because of the CCC’s efforts, the driver shouldn’t have to remove their phone from their pocket. The Digital Key standard would use a combination of Bluetooth and ultra-wideband and would work across a variety of different cars.

Today I can open my Tesla and drive it using the Tesla app on my smartphone, but it requires Internet connectivity, and the Tesla servers have to be working. Indeed, I’ve found myself stuck on more than one occasion, so I never leave home without my key fob. And Tesla’s solution is proprietary to Tesla. (Newer Teslas have a phone key that works using Bluetooth to open the car without having to open the app.)

A standardized digital key would work across all phones and most vehicles, making it easy for people to get credentials for their car on their handset and open their vehicle. This would be especially useful for rental cars or fleet vehicles. The digital key would also work locally without requiring internet access or an intervening server, which means you just need the phone and the car to work.

Other automotive members of the consortium include DENSO, Ford, General Motors, Honda, Hyundai, Mercedes-Benz, and Volkswagen. Daniel Knobloch, a vice president at the CCC and a wireless systems expert at BMW, said to me in an interview that a UWB version of a digital key was released in 2021 and that a few early adopters were asking a lot of questions about how it would work.

As part of the standardization process, the focus has been on security and ensuring that adding this feature doesn’t lead to more car thefts. Knobloch said that part of the standard included a dedicated and isolated chip in the smartphone to store the credentials for a car’s digital key. Other necessary elements for the standard include figuring out how to share keys for a vehicle among a group of users, how to transfer ownership in the case of a sale (or rental agreement ending), and how to localize the key either inside or outside of the car.

The standard uses precision location from UWB to figure out where a person is in relation to the inside or outside of the car and UWB plus Bluetooth to transfer the credentialing data during a secure session. Knobloch said that the other big challenge was getting the industry to agree on a standard for a digital key, but the CCC appears to be the winning choice. I would expect him to say nothing less, but the roster of carmakers is impressive.

Knobloch said that carmakers want this digital key to become a standard feature as opposed to something consumers would pay an extra subscription for. We’ve seen in recent years carmakers charge subscription fees for new tech features such as remote start or even heated seats.

He also said that once UWB radios are installed in new vehicles we might see new use cases for the technology. “As carmakers put the hardware in the cars, other use cases like child presence or gesture detection are a nice, low-hanging fruit, but from CCC’s perspective we’re really focused on the digital key ecosystem,” said Knobloch.

As for timing, Knobloch couldn’t say when consortium members will replace their fobs with digital keys, but as a consumer, he’s ready for it. He plans to give up a physical fob or key as soon as he’s able.

Read the full article from Stacy on IoT here.