Last year, Apple’s Find My received another boost with the release of the U2 chip included in the iPhone 15, Apple Watch 9, and Apple watch Ultra 2. With the U2 chip, Find My’s precision finding capabilities increased almost 5 times, as shown in this clip:
While Precision Finding has been available since the iPhone 11, we see the iPhone 15 showing where it can lead us in the future. So today, we’re taking a look at Ultra-Wideband (UWB) which is the technology that powers Precision Finding, and what makes it stand out from many competing location technologies today.
Accuracy
Most current Bluetooth and WiFi location systems rely on the Received Signal Strength Indicator (RSSI) which is accurate between 1-5 meters and is heavily impacted by the environment. Due to the nature of the UWB signal, UWB location systems can use Time of Flight (ToF) methods that were previously much more difficult on Bluetooth and WiFi. Using ToF results in greater accuracy with many commercial systems having accuracy ranges of between 10 to 30 centimeters - up to a 50x improvement in distance accuracy. Utilizing sensor fusion, augmented reality or Angle of Attack (AoA) methods can find the angle between devices, meaning 1 device can locate another in 3D. The outcome - where Bluetooth has you playing hot and cold, UWB on an iPhone points you to exactly where your tag is.
Range
While current-gen AirTags only use UWB in shorter ranges, Apple’s U2 tags can report accurate location well beyond 50 meters and other industry solutions can reach up to 200 meters with amplification, all while retaining the high level of accuracy. This is very competitive with WiFi and Bluetooth which also peak around 100-200 meters of range. However, RSSI is a wave strength measurement that follows the inverse square law, with small changes in RSSI covering larger distances. ToF is based on time and the speed of light resulting in much more consistent accuracy at longer distances. So while RSSI caused Bluetooth and WiFi accuracy to degrade significantly over large ranges, UWB’s ToF methods stay accurate even at the end of its range.
Data Transfer
Bluetooth is the current standard for IoT devices, but UWB can transfer more data, transfer it faster, and use 10x less energy. While not able to transmit as much as WiFi 6 or 4G/5G, UWB could overtake the IoT space with its ability to transmit large amounts of data over 10-20 meters with way more efficiency, leading to longer device lifespans.
Integrations
Apple, Google and Samsung have all integrated UWB technology in their flagship phones, opening up many possibilities connecting with and leveraging mobile devices for interacting with UWB tags and devices. Apple’s Nearby Interaction framework and new U2 chip show a potential long-term plan in helping developers create new experiences with UWB. And while many of the improvements of the U2 chip seem to only work with other U2 devices, they are still compatible with the previous U1 chips and third party devices.
Radar
While not particularly applicable to us at Navv, we found the radar capabilities of UWB too fascinating to not mention. UWB can be used as radar at shorter ranges and was originally a defense technology used to detect IEDs through objects. Currently, it’s also being used to monitor vital signals like heart rate, respiratory rate, gait and fall detection in healthcare.
UWB can revolutionize indoor location like GPS did with outdoor location, but it provides other great benefits as well. The buy-in of the major mobile providers shows that they believe too, opening up a whole world of possible applications. In the next post, we’ll examine how the benefits of UWB will impact healthcare applications.
