How Bluetooth 6.0 channel sounding redefines distance measurement

Although the concept is still new, its technical implications are clear, and Jaworowski was able to walk us through the differences in a highly practical way.

To illustrate the changes compared to earlier Bluetooth versions, he demonstrated a setup using Silicon Labs development kits. One board acted as the initiator, the other as the reflector. While the system ran, the screen displayed two live measurements: one based on RSSI and one based on channel sounding. The contrast between them was immediate. The RSSI values fluctuated constantly, while the channel-sounding measurements remained stable.

As Jaworowski put it, “RSSI has been used for years, but it’s extremely sensitive to interference. Its accuracy is in the range of meters. Channel sounding, on the other hand, uses phase-based ranging and round-trip-time measurement. That gives us accuracy in the range of 30 to 50 centimetres.”

He clarified how the two elements complement each other. Phase-based ranging determines distance by analysing phase differences across multiple frequencies, while round-trip time measures how long it takes for a signal to travel between devices. The combination reduces noise, improves reliability and, importantly, introduces stronger security around the measurement itself.

This level of precision enables new applications across several fields. When asked which sectors could benefit the most, Jaworowski did not point to a single dominant area. Instead, he noted that improvements in accuracy and security make the technology broadly useful. “In industry, you can imagine better asset tracking. If you have a factory and you need to find a tool, you can now do it with greater accuracy,” he said. The same applies to safety systems designed to detect entry into restricted zones.

In automotive, the relevance is equally clear. Bluetooth-based keyless entry systems can use channel sounding to verify distance more reliably, making relay-style signal manipulation significantly harder. And for IoT, the logic extends naturally: door locks and other access-control devices can detect how far the user is from the entry point, relying on distance measurements that are far more resistant to interference. “All industries will benefit from this technology,” Jaworowski remarked. “The use cases are really wide.”

As with any new radio function, engineers will face challenges when implementing channel sounding. The most important one is balancing energy consumption with measurement accuracy. Polling more often or collecting more samples increases precision but also drains the battery more quickly. Jaworowski emphasised that this is not a limitation of the technology itself, but rather a design decision that must be managed carefully. “If devices aren’t moving, it doesn’t make sense to measure every ten seconds,” he explained. Bluetooth 6.0 allows developers to adjust parameters dynamically, reducing measurement frequency when possible and restoring higher accuracy only when needed.

Chip selection becomes a key factor as well. Devices that support multiple antennas can significantly improve ranging performance, and manufacturers who provide robust processing algorithms offer an advantage during integration. Another practical strategy is to combine Channel Sounding with sensors such as accelerometers. This way, distance measurements occur only when movement is detected — a simple but effective approach to preserving battery life.

Looking toward the future, Jaworowski sees Channel Sounding not as an isolated breakthrough, but as part of a broader evolution of Bluetooth-based location technologies. The ecosystem already includes RSSI, Angle of Arrival and Angle of Departure. Channel Sounding adds another tool, one that is less expensive to implement than many competing solutions offering similar precision. According to him, this combination could accelerate the adoption of accurate indoor positioning much faster than in previous generations.

To put this in perspective, he drew a parallel with the early days of GPS. “In the late 90s and early 2000s, GPS changed how we move between cities. No one uses paper maps today. We simply expect navigation to work,” he said. The same shift is now taking place on a smaller scale. Everyday objects — wallets, bags, keys — increasingly feature built-in localisation chips. Technologies like channel sounding reinforce this trend by making object detection more reliable in dense indoor environments where GPS cannot operate.

As adoption of Bluetooth 6.0 grows, the industry will begin to integrate distance-based functionality more naturally into consumer and industrial devices. While the transition is still at an early stage, the technical foundation appears robust, and the range of practical applications is already broad. Jaworowski summarised the outlook simply: “This is a technology that will make everyday localisation easier. We are at the beginning of that change.”

As the Bluetooth ecosystem continues to evolve, discussions around technologies like Channel Sounding will likely return during next year’s edition of Evertiq Expo Warsaw, scheduled for 22 October 2026. The event will once again bring together engineers, developers and industry specialists to exchange perspectives on the solutions shaping modern electronics — both on the component and system level.