Apple’s UWB Efforts—Past, Present, and Future

Ultra-Wideband (UWB) is a location communication technology that provides accurate, cm-level, real-time ranging and positioning information to deliver the relative location of devices by measuring the time it takes a signal to travel between them. Tags, anchors, vehicles, smartphones, wearables, and more have the ability to take advantage of UWB technology. Its wide bandwidth provides stable connectivity with minimal interference, low battery consumption, and precise positioning at a frequency range of 3.1 to 10.6 GHz.

While UWB has only recently come to the forefront of many companies’ efforts, the technology has been around for some time; the Federal Communications Commission (FCC) first authorized its use for military radars and heart monitoring in 2002. At the time, UWB was an immature technology, providing lower-than-expected performance at a high cost, which limited its initial uptake. Now, after much Research and Development (R&D), UWB is cheap, small, and effective. The new 802.15.4z standard is likely to aid the development of UWB, adding new features to the 802.15.4 standard including a secure ranging scheme and long ranging capability, as well as providing backward compatibility for the older standard. Work by the Fine Ranging (FiRa) Consortium, the UWB Alliance, and the Car Connectivity Consortium (CCC) is also helping to increase awareness of the technology and ensure that new ranging capabilities are developed. An increasing number of companies are exploring the use of UWB, including Apple, which has been working on adding UWB to a number of different device types.

Apple has been working on UWB solutions for its devices for some time now. In September 2019, the company released its iPhone 11 lineup, which featured the UWB-enabled U1 chip. While the company originally kept fairly quiet about the feature, it was expected that it would be used for AirDrop, smart home applications, security, Augmented Reality (AR), and other positioning use cases. AirDrop, Apple’s wireless transfer system, will benefit from UWB due to its spatial awareness capabilities, enabling two UWB devices to understand when they are pointed at each other. This integration of UWB into iPhones also suggests that the technology will be added to other Apple devices, such as MacBooks, Apple Watches, iPads, and AirPods, for similar use cases. AirPod Pros could also leverage the technology for their spatial audio and dynamic head tracking features, providing the directional information required to adjust the frequencies in each ear. It is unclear if Apple has already integrated UWB into its AirPod Pros as of now, but if it has yet to, it is likely that UWB will be added moving forward. There are also rumors that Apple will be opening up its Software Development Kit (SDK) for developers to use in the future, but no confirmation or expected timeline have been announced.

It is expected that Apple will also be releasing personal tracking devices, AirTags, in which UWB will provide a method of locating lost tagged items using another UWB-enabled Apple product. The company has also patented UWB beacons, iBeacons, which, when attached to objects, send out a signal to an UWB-enable Apple device to help provide cm-level real-time location information.

In June 2020, Apple also announced its Car Key, which enables iPhones or Apple Watches to unlock and start vehicles wirelessly and is currently debuting in BMW vehicles. While it currently uses Near-Field Communication (NFC), the company is working on an industry-wide standard that would enable the solution to utilize its UWB-enabled U1 chip or other future Apple UWB technologies, with the first iPhones expected to utilize UWB for the Car Key in 2021 with iOS 14. It is also expected that the technology will be available in Apple Watches in the future. For the time being, users can pair their devices with a Car Key-enabled vehicle, allowing them to hold up the device to unlock the vehicle. Extra authentication via Face ID or Touch ID can also be enabled. The CCC is working on developing Digital Key 3.0, which will leverage UWB and BLE, with BMW, Jaguar, VW, and NXP all having demonstrated or released UWB solutions.

While not necessarily strictly an Apple UWB development, a new use case for the technology has been brought about by the COVID-19 pandemic: contact tracing using UWB-enabled devices to track when people come in close contact with each other, ensuring that if a person is infected, all those who came into close contact with them are alerted about the risk, allowing them to self-isolate and reducing further spread. This application could be used by any UWB-enabled device, so it is likely that Apple will be investigating the potential of using its technology for contact tracing.

While Apple is currently the only smartphone vendor offering an UWB solution, it is expected that others will follow. Companies such as Samsung, Huawei, Xiaomi, Oppo, and Sony are expected to be working on UWB technology for their devices, potentially allowing them to develop similar products to Apple’s U1 chip and thereby allowing their devices to offer location-based features. Many of these companies (in particular, Samsung, Sony, Xiaomi, and Oppo) are also members of the FiRa Consortium or UWB Alliance, further suggesting that they are working on or have an interest in the technology.

Many challenges have had to be overcome to allow UWB to be where it is today. In particular, the integration of antennas into an UWB system, which affects its performance, has been a common problem among a number of UWB market players. Antenna size has been a particular issue, especially when attempting to integrate UWB into small devices such as tags, smartphones, wearables, and sensors. In order to overcome this challenge, technology providers have undertaken a large amount of R&D to reduce the antenna size and ensure that it doesn’t affect the form factor of the final device. Other challenges within the UWB market have centered around the cost of the components and infrastructure, which is currently higher than that of alternative technologies due to the technology’s wide band, low latency, low interference, high accuracy, and immaturity, as well as the low awareness around UWB compared to BLE and Wi-Fi, which makes it harder for companies to develop and market new UWB devices and in turn does not help raise awareness.

It is recommended that these companies, as well as other consumer device vendors, look into offering devices with UWB solutions, as the technology will open up new use cases and opportunities for their devices. Offering advanced methods of transferring data directly to another device, wirelessly unlocking and starting vehicles hands-free, wirelessly paying for products, and accurately locating lost items and pets with a device that a consumer would already own would make that particular device stand out from its competition.

Connectivity companies should also consider looking into or expanding their UWB offerings to enable a wide variety of use cases across different industries, including consumer devices, smart homes, smart cities, asset tracking, personnel tracking, automotive applications, and more. Offering a range of customizable solutions will allow the technology to be utilized for many different purposes, providing a wider market reach. Conversely, concentrating on one market and/or use case will help to ensure that the technology works exactly as required and can be targeted at specific companies. The more companies offer and utilize UWB technology, the more likely it is that the technology will become ubiquitous and as common as Wi-Fi and BLE, offering secure and accurate location information.

There has been a large amount of recent growing momentum in the development of UWB, with a number of chipset vendors, technology providers, and device developers adding to or growing their UWB offerings, including Decawave/Qorvo, Humatics, Inpixon, Juniper Networks, Sewio, SPARK Microsystems, TSINGOAL, UWINLOC, and WISER Systems. These companies, and others, often form partnerships to ensure fully scalable, customizable, integrated, and interoperable solutions are developed for different use cases.