Bluetooth® Channel Sounding will
expand the market presence of
distance awareness

Digital key solutions

RSSI-based Bluetooth^® LE digital key solutions have existed for some time. Both Bluetooth^® LE-enabled fobs and phone-as-key solutions can be used to lock and unlock doors, gates and garages, bicycle locks, safes, cabinet, and drawer locks, among other devices. Bluetooth^® Channel Sounding provides an additional layer of protection against man-in-the-middle relay attacks, removing a key area of concern when adopting Bluetooth technology for digital key and access control solutions, compared with UWB, while also providing sufficient accuracy and low enough latency for most deployment scenarios.

Today, there is strong momentum for multi-protocol access control solutions, particularly in the automotive space, with the backing of the Car Connectivity Consortium and its Digital Key Release 3.0 Specification, which combines UWB, Bluetooth^® LE, and NFC. Similarly, the unveiling of Aliro from the Connectivity Standards Alliance (CSA) in 2023 aims to standardize the communication protocol between access readers and user devices such as smartphones, wearables, and other devices to provide a more convenient and consistent experience for access control. Meanwhile, other organizations, such as the Intelligent Connected Car Open Alliance (ICCOA) and Intelligent Connected Car Ecosystem Alliance (ICCE) in China, are also investigating a similar approach to the CCC, combining UWB, Bluetooth^® LE, and NFC technology.

However, given that UWB is not yet a ubiquitous technology and the fact that it will come at additional cost and complexity, many in the industry believe that OEMs, outside of the high-end and premium tiers of the market, will view Bluetooth^® Channel Sounding as a viable, cost-effective solution for automotive, home, and building access, taking advantage of the ubiquity of Bluetooth® LE technology in smartphones and other devices. Therefore, Bluetooth^® Channel Sounding has the potential to help scale up digital key and phone-as-key deployments across automotive, home, enterprise, and industrial access control use cases.

In addition to standalone Bluetooth^® Channel Sounding digital-key solutions, Bluetooth^® Channel Sounding will also likely have a complementary role to play with UWB technology, with access control solutions potentially leveraging Bluetooth^® Channel Sounding to determine distance when the user is further away, and hand over to UWB for unlocking and in-cabin use cases. Here, the use of Bluetooth^® Channel Sounding could further reduce the power consumption of access control solutions that utilize UWB.

Asset tracking

Bluetooth^® Channel Sounding can bring significant performance and security enhancements to indoor asset-tracking applications while also enabling some reduced complexity deployments when compared with previous solutions. In enterprise environments, such as hospitals, personnel can leverage smartphones to track high-value equipment more readily, improving productivity and preventing the loss of critical assets.

In retail environments, high-value equipment can be equipped with dedicated Bluetooth® Channel Sounding tags and send alerts when they are moved out of specified areas. In warehouse environments or construction sites, personnel can track Bluetooth^® Channel Sounding-enabled tools without needing to install a more complex RTLS infrastructure with multiple locators.

Other high-value assets can activate alarms if they are suddenly moved outside of their predetermined location, preventing theft. These solutions can complement more scalable asset-tracking implementations based on RSSI and AoA/AoD to help track hundreds to thousands of assets.

In addition, Bluetooth^® Channel Sounding can be combined with other techniques, such as direction finding, to enable even further accuracy and security to their asset tracking platforms.

Human-interface devices (HID)

By offering centimeter-level distance measurement capabilities, a whole host of peripheral and accessory devices can now accurately determine their relative position from platform devices such as smartphones, PCs, tablets, and smart TVs. Devices such as mice, keyboards, and controllers could automatically switch between active and inactive states as they approach or are separated from the source PC. For example, when someone picks up their laptop to use it, an active wireless keyboard or mouse may turn inactive once the laptop moves from a pre-configured distance away from them. Alternatively, someone placing their game controller next to their laptop could activate it. This could help to improve the end-user experience while extending the battery life of those devices

Proximity interactions and automation

Another potential application for Bluetooth^® Channel Sounding is the ability for a platform device to detect proximity to an end user’s smartphone or smartwatch and automatically lock or unlock the screen once they come within a certain threshold. For example, a user equipped with a Bluetooth^® Channel Sounding-enabled smartwatch could approach their PC and have it automatically unlock and then lock again once they move a certain distance away. This could also potentially detect who is using the PC and switch between their login profiles.

Bluetooth^® Channel Sounding could enable a whole host of innovative user experiences to support proximity/geofencing-based automation. For example, holding a smartphone close to a home appliance could bring up a relevant control panel automatically rather than searching through the installed apps on the device. Much like door locks, other equipment such as lighting, audio devices, and thermostats may also be able to respond to a person’s presence in different rooms. This could be used to personalize the environment to the user’s specific preferences.

In hospital settings, personnel could access patient records automatically on their device as they visit them. Usage restrictions could also be set to prevent unauthorized users from interacting with assets, appliances, or equipment unless somebody with the right credentials is near the device. This same technology can also help ensure a smooth device onboarding and provisioning process based on proximity.

Human-machine interface (HMI)

Conversely, there may be use cases in which personnel safety can be enhanced by only enabling the operation of potentially dangerous equipment or machinery once the user is a safe distance away. For example, HMIs that operate robotics, machinery, appliances, and tools within commercial and industrial environments could benefit from Bluetooth^® Channel Sounding’s ability to more accurately determine their position compared to RSSI solutions, guaranteeing they are at the required distance from the equipment to operate it safely.

The future of Bluetooth Channel Sounding

Given the early lifecycle of Bluetooth^® Channel Sounding technology, it is too soon to predict what new types of use cases and device types may emerge over time. Some other potential future use cases may include self-optimization and configuration of devices, such as Bluetooth smart lighting, to help optimize system performance. With the ubiquitous presence of Bluetooth^® LE in smartphones and other platforms, ABI Research expects that many new use cases will emerge as the rollout Bluetooth^® Channel Sounding accelerates in the coming years.

Learn more about How Bluetooth^® Channel Sounding Will Shape the Future of Device Positioning.