The New and Improved Bluetooth® 6.0
The highly anticipated Bluetooth Core Specification Version 6.0 is finally here, marking a significant leap forward for Bluetooth technology. The update includes substantial enhancements to existing features including advertising and isochronous channels, as well as breakthrough new features supporting location services. These upgrades and enhancements continue the standard’s relentless expansion of Bluetooth’s feature set to unlock more use cases with interoperable and secure performance.
Review Bluetooth 6.0 Features
Each update to the Bluetooth spec standardizes new functionality to unlock new use cases or optimize existing ones. For instance, Bluetooth 5.1 enhanced location services by introducing Direction Finding, Bluetooth 5.2 took the next step in audio streaming by standardizing Bluetooth Low Energy (LE) audio, and Bluetooth 5.3 and 5.4 provided transformative enhancements to device networking with periodic advertisements.
So, what distinguishes Bluetooth 6.0 from its predecessors, and what new features can users look forward to?
Bluetooth 6.0 is a major update over recent, incremental updates, delivering substantial enhancements to audio streaming, device networks, and especially location services. Some of the most significant impacts of these new features are strengthened security and greater accuracy in distance measurement. Let’s look at all the upgrades we are excited about:
- Bluetooth Channel Sounding – one of the most notable features of Bluetooth 6.0 is the addition of channel sounding, which enables two-way ranging between two Bluetooth LE devices. This upgrade is set to revolutionize distance measurement accuracy and ranging, and we will discuss it more in this blog later.
- Decision-Based Advertising Filtering and Monitoring Advertisers – These features improve the scanning efficiency of a Bluetooth device. While decision-based advertising filtering helps improve the efficiency by reducing time spent on scanning data packets, monitoring advertisers use host controller interface (HCI) to track when the devices move in and out of range.
- ISOAL Enhancement – Increases reliability in data transmission and reduces latency that comes with the generation of framed PDUs.
- LL Extended Feature Set – This feature allows devices to exchange link layer features that they support.
- Frame Space Update – It enables negotiable spacing between isochronous streams and connection events, optimizing data throughput.
Bluetooth Channel Sounding
As previously stated, Bluetooth Channel Sounding is one of the most notable features of the new Bluetooth 6.0. It enables connection-oriented 2-way ranging, minimizes multipath effects by supporting up to four antenna paths between devices, and secures distance measurement against man-in-the-middle attacks. This feature signifies a major breakthrough in Bluetooth technology compared to existing ranging between Bluetooth Low Energy devices using received signal strength (RSSI).
How does Bluetooth Channel Sounding work?
1. It uses phase-based ranging (PBR) and round-trip time (RTT) measurements to enable fine ranging between two connected Bluetooth LE devices.
In a Bluetooth Channel Sounding procedure, one device identifies as the initiator while the other identifies as the reflector. The initiator transmits the signal, which is detected and received by the reflector device.
These devices then use PBR, RTT, or both to coordinate ranging between up to 72 channels within the 2.4 GHz spectrum, while also using one to four antenna paths between the two connected devices.
RTT uses the time of flight (ToF) to estimate the distance between the initiator and the reflector. The time of arrival (ToA) and time of departure (ToD) is recorded for both the devices and the difference between them is used to precisely calculate the distance between these devices. The standard also provides setup and calibration processes to compensate for clocking differences between both devices.
CS SYNC packets exchanged between initiator and reflector
PBR utilizes the difference between the phase of the transmitted and received signal to calculate the distance between the initiator and reflector devices. Comparing the phase difference between these devices helps accurately measure the distance between them.
CS Tone exchanged between initiator and reflector
Each antenna path exercised in each step
2. It supports up to four antenna paths between devices with eight possible antenna combinations
Another way Bluetooth Channel Sounding enhances the robustness and accuracy of distance measurement is by its ability to support multiple antenna paths. This allows a signal to travel using alternative routes in case of any interference or noise and is particularly helpful for devices like asset tags.
3. Can be combined with Angle of Arrival / Angle of Departure (AoX)
Bluetooth Channel Sounding can be combined with AoA and AoD to benefit applications like indoor positioning or asset tracking, where combined direction finding and distance estimation can improve user experience.
4. Offers enhanced security features
Bluetooth Channel Sounding offers multiple built-in security features that help reduce man-in-the-middle attacks and relay attacks. These features include a distributed random bit generator (DRBG) which helps to randomize aspects of ranging, such as channel selection. Additionally, all ranging and data exchange occurs over an encrypted connection.
5. Seamless integration without additional components
One of the other significant advantages of Bluetooth Channel Sounding is that, as a standardized Bluetooth feature, it promises to be widely available in products, with interoperability enforced through a formal qualification program. Many target applications requiring location services such as distance estimation already require Bluetooth LE for a data channel. In those applications, Bluetooth Channel Sounding can be enabled without any additional components or hardware space, which reduces cost of implementation compared to other technologies such as ultra-wideband (UWB). It also increases simplicity, improves battery life, and even expands compatibility with a multitude of devices.
Bluetooth 6.0 Target Applications
With an array of new features and developments to look forward to, the new Bluetooth 6.0 is set to have a significant impact on the performance and efficiency of connected wireless smart devices. This improvement is primarily driven by the introduction of Bluetooth Channel Sounding, which targets applications in two categories: localization and proximity awareness.
- Localization: this includes applications like pet and asset trackers, which utilize locator devices to find the exact position of a tracking device.
- Proximity awareness: this includes applications like smart locks and keyless entry systems, which utilize the enhanced security features to restrict and control access to secure spaces and systems. Applications include smart locks, geofencing, FindMy, and vehicle keyless entry. In these applications, security is of utmost importance to ensure that no unauthorized user is able to get access to the network.
Silicon Labs Bluetooth 6.0 and Bluetooth Channel Sounding Offerings
Silicon Labs has a long history of pioneering innovation through devices that help transform IoT. We are proud to announce that our robust Bluetooth portfolio and industry-leading Bluetooth architecture will now support Bluetooth 6.0 and Bluetooth Channel Sounding. Our team of industry experts have curated single-antenna and dual-antenna solutions to meet a broad range of application needs.
The RB4198A is our single antenna solution which is more suitable for applications that require lower power consumption like an asset tracker, whereas the DK2606A (which will be available December 2024) is our dual antenna solution which is ideal for size-constrained applications like key fobs.
To learn more about our Bluetooth portfolio and our Bluetooth Channel Sounding solutions, visit our webpage or contact our sales team now.
