Bluetooth® Channel Sounding
Bluetooth® Channel Sounding is a new secure, fine-ranging capability that promises to enhance the convenience, safety, and security of many Bluetooth connected devices. By infusing billions of everyday devices with true distance awareness, Bluetooth® Channel Sounding unlocks a world of possibilities for developers, freeing them to imagine and create innovative experiences. From increasing the security of digital keys to improving the performance of ‘find my’ solutions, Bluetooth® Channel Sounding will enhance our connection with our devices, one another, and the world around us.
Overview
Overview
View the Bluetooth® Channel Sounding landing page
PRESS RELEASE
PRESS RELEASE
View the release
QUOTES
QUOTES
Quotes from the industry regarding Bluetooth® Channel Sounding
SCHEDULE A BRIEFING
SCHEDULE A BRIEFING
Request a briefing with the Bluetooth SIG
Quotes
FAQ
Why is the feature called Bluetooth® Channel Sounding?
Channel sounding is a well-established term in radio frequency (RF) engineering that describes a technique used to characterize the properties of a radio communications channel. Since this new Bluetooth feature is used to calculate the precise distance between devices by characterizing the phase and time delay of a radio signal sent between them, Bluetooth® Channel Sounding was deemed an appropriate feature name.
What is the expected accuracy of Bluetooth® Channel Sounding?
The Bluetooth® Channel Sounding feature was designed to achieve centimeter-level accuracy, which means the accuracy of a distance measurement should be plus or minus tens of centimeters of the actual distance. In early implementations of the Bluetooth® Channel Sounding feature, we are already seeing accuracy levels of +/- 20 cm.
What is the maximum range Bluetooth® Channel Sounding can accurately measure distance?
The maximum range of Bluetooth® Channel Sounding depends on several factors, with one of the most significant being the transmission power of the Bluetooth devices involved. If both devices can transmit at the maximum allowed power level, accurate measurements at distances up to 150 meters can be achieved.
Can existing products be upgraded to add support for Bluetooth® Channel Sounding?
This is manufacturer dependent. Bluetooth® Channel Sounding introduces an entirely new protocol stack, including a Physical Layer (PHY) which may require a Bluetooth Low Energy (LE) integrated circuit (IC) upgrade to enable support for the feature. However, you should check with your device and/or product manufacturers to ultimately make this determination.
Does the Bluetooth® Channel Sounding feature define a distance measurement algorithm?
No. The Bluetooth® Channel Sounding feature does not include a distance measurement algorithm. It provides standardized techniques to determine signal phase and time delay information which can be used by an algorithm to calculate the distance between two devices. Since the appropriate distance measurement algorithm needed may vary depending on the use case, it was determined the Bluetooth® Channel Sounding specification would not define a specific algorithm. The necessary algorithm for the use case can be sourced or developed independently.
Will not having a single standardized algorithm impact the interoperability between devices from different manufacturers?
No. The algorithm only needs to be implemented by one side of the channel sounding session. The absence of a specified algorithm does not affect interoperability between two devices.
Are there use case specific Bluetooth profile specifications that use the Bluetooth® Channel Sounding feature?
There is a new Bluetooth® Ranging Profile specification in development. However, the ranging profile is not designed to be use case specific. This GATT specification will define how an application can configure and read results from a channel sounding procedure. The profile targets a broad range of use cases, including digital keys, locks, Find My solutions, and HMI (human machine interface) control solutions, to name a few.
Can Bluetooth® Channel Sounding be used in conjunction with other Bluetooth positioning features such as Bluetooth® RSSI and Bluetooth® Direction Finding?
Yes. Bluetooth® Channel Sounding can be used in conjunction with other Bluetooth positioning features, including RSSI and direction finding. For example, we are aware of upcoming solutions that plan to combine the use of Bluetooth® RSSI and Bluetooth® Channel Sounding, where RSSI will be used to determine presence, proximity, and course ranging when the devices are farther apart and Bluetooth® Channel Sounding will be used to increase accuracy as the two devices approach each other.
When are Bluetooth® Channel Sounding products expected to be available in the market?
We expect to see initial enabling technology products (e.g., chips, modules, and stacks) available this year and end-use products (e.g., mobile phones, tags, and fobs) supporting Bluetooth® Channel Sounding starting in 2025.