Also see The Biggest iPhone News Is a Tiny New Chip Inside It | Wired
"You've heard of Wi-Fi, Bluetooth and 5G. Now it's time to learn another wireless communication term, because Apple has built it into its new iPhone 11 and 11 Pro smartphones. The technology, ultra wideband, or UWB, lets you pinpoint the exact location of phones, key fobs and tracking tags, helping you find lost dogs or automatically unlock your car.Apple built UWB into the iPhone 11. Here's what you need to know (FAQ) | CNET
UWB calculates precise locations by measuring how long it takes super-short radio pulses to travel between devices. It's well suited to Apple's rumored tracker tags. But UWB could also bring new smarts to your house, car and devices. Right now its use cases are limited, but UWB could lead to a world where just carrying your phone or wearing your watch helps log you in to everything around you and log you out when you leave."