With a post on the official blog, Google explains how the radar system integrated in the next Pixel 4 will work. It will improve facial unlocking
In the new Pixel 4, arriving after the second half of October 2019, will be integrated a radar called "Soli" and developed by Google's Advanced Technology and Projects team. Thanks to this radar, announces Big G, the way we use the smartphone could change completely.
Soli is, technically, a small "motion-sensing radar". That is, a kind of sensor that understands when we are close to the smartphone and can pick up our movements. The information about these movements, then, can be processed by artificial intelligence to give us the possibility to use a new form of gestures: the "Motion Sense" feature will work without touching, just move your hands in front of the screen to control the smartphone. With Soli and the Motion Sense feature, in practice, 3D gestures will arrive. Without touching the screen we'll be able to jump from one song to another, suspend alarms or mute phone calls and much more.
If what we've described so far seems futuristic (it reminds a lot of Tom Cruise's gestures in Minority Report), with the Soli radar you'll be able to do more common things like facial recognition to unlock your smartphone. But, assures Google, it will be a Face unlock much more advanced than those we use today. And to test it, Google paid $5 for passersby to agree to have their faces photographed.
"Other phones require you to lift the device fully, pose, wait for the phone to unlock, and then swipe to access the Home screen. Pixel 4 does all that in a much more streamlined way. When you reach for Pixel 4, Soli proactively activates the facial unlock sensors, recognizing that you might want to unlock the phone. If the facial unlock sensors and algorithms recognize you, the phone will activate as you pick it up, all in one motion. Better yet, facial unlocking works in almost any orientation, even if you're holding the smartphone upside down, and you can also use it for secure payments and app authentication."
No cloud for Face unlock
Face unlocking requires the recording of biometric data: our face is the most identifiable part of our body, and data about it is definitely "sensitive" from a privacy perspective. For this reason Google has made a clear choice: the data relating to our face will not be processed in the cloud but directly on the Pixel 4, where they will be stored within the security chip Titan, equipped with encryption. There will be no exchange of facial data either with Google's servers or with other services and apps from Mountain View or third-party companies.