The November 6th Wireless Wednesday video gave an overview of a new feature in Bluetooth 6 called channel sounding, which allows two Bluetooth devices to securely and accurately measure the distance between them. In today’s blog we will explore some details of the new standard and the improved security offered by channel sounding. This standardization of Bluetooth ranging will bring a new dimension to how we interact with a technology that is integrated into our daily lives.
The Bluetooth 6 standard setups up two components that enable the standardized channel sounding procedure - Ranging Service (RAS) and Ranging Profile (RAP). These two specifications are now officially released by Bluetooth Special Interest Group (SIG). As shown in Figure 1, these components provide the gasket between applications and the capabilities provided by Bluetooth 6 Core Specification. NXP has been involved in the development of channel sounding from the beginning and NXP software engineers contributed to the development and testing of the RAS and RAP specifications, which has enabled NXP to integrate pre-released versions of the RAS/RAP into the MCUXpresso SDK.
The RAS/RAP specifications include many features to offer higher security. In the Ranging Service, the security permissions for characteristics, such as the ranging data, require encryption. This ensures sensitive data is protected. For the ranging profile, provisions are made for the Ranging Requestor (RREQ) to decide if the channel sounding security level capabilities available for the ranging process are acceptable for the goals of the application. The RAP specification also recommends that the highest level of security supported by the Ranging Requestor and the Ranging Responder should be chosen. In addition, the RAP design provides the tools needed to ensure that the channel sounding procedure is resilient to attacks. There are 4 levels defined in the Core Specification for channel sounding. These levels can be used to reduce the effectiveness of physical attacks in the RF domain so that the ranging estimations can be trusted. Developers can choose between the levels based on their use cases and desired goals.
Learn more about Bluetooth channel sounding from NXP’s channel sounding blog.
The improved security and standardization offered by Bluetooth 6 channel sounding will enable many new use cases and drive quick adoption of the new technology. At the system level, NXP’s wireless SoCs and MCUs offer integrated security to not only secure the Bluetooth connection but to also ensure the system can meet new security regulations enacted or being developed by countries globally. The recently announced MCX W72 includes full support for Bluetooth 6 channel sounding and NXP’s integrated EdgeLock Secure Enclave (Core Profile) to ensure the highest levels of security. Combined with the enhanced security in the Bluetooth 6 specification, developers can create both secure connections and secure devices.
Donnie Garcia began his semiconductor career as an applications engineer for 8- and 16-bit MCUs. He has helped define and design low-power MCUs for consumer and industrial applications and currently works as a Product Manager for wireless MCUs. Donnie has authored nearly 20 technical publications (webinars, whitepapers, articles, application notes, engineering bulletins). He spends his weekends enjoying the outdoors around Austin.
