Revolutionize Distance Measurement- BLUETOOTH® Channel Sounding for Max Precision & Security

Download Infographic
Learn More about the nRF54L SoC
Learn More about the nRF54L Dev Kit
Download Infographic
Learn More about the nRF54L SoC
Learn More about the nRF54L Dev Kit

Revolutionize Distance Measurement

Bluetooth® Channel Sounding for Max Precision & Security

Introduced with Bluetooth 6.0 in 2024, Bluetooth Channel Sounding measures the distance between two connected devices using Round Trip Time (RTT) and Phase-Based Ranging (PBR). This technology is crucial for applications like smart locks, car keys and asset tracking.

Annual Bluetooth location service device shipments

A bar graph illustrates the expected growth in annual Bluetooth location service device shipments from 2024 to 2028. There is an expected 22% CAGR in shipments from 2024 to 2028.

  • 2023- 210 million shipments
  • 2024- 255 million shipments
  • 2025- 318 million shipments
  • 2026- 388 million shipments
  • 2027- 466 million shipments
  • 2028- 563 million shipments

Round Trip Time (RTT)

The initiator sends a message to the reflector, which responds. The distance is calculated by measuring the return time. Since RTT is hard to spoof, this method ensures secure distance measurement.

A graphic shows an example of the RTT protocol with a smart phone unlocking a smart lock over Bluetooth. The difference in time between the Initiator (smart phone) sending a packet and the Reflector (smart lock) receiving the packet is represented as ToFI-R. The difference in time between the Reflector sending a packet and the Initiator receiving the packet is represented as ToFR-I. The equation calculating RTT is: RTT= ToFI-R + ToFR-I.

Phase-Based Ranging (PBR)

The initiator sends an unmodulated signal to the reflector, which returns an identical wave. The initiator measures the delay using phase differences at multiple frequencies to calculate distance, ensuring high precision.

A graphic shows an example of the PBR protocol with a tablet getting the location of a forklift over Bluetooth. The delay in frequency of a signal sent from the Initiator (tablet) to the Reflector (forklift) and a frequency sent from the Reflector to the Initiator is noted as the Phase difference.

Main Advantages

  • High-accuracy distance measurement (cm-level)
  • Enhanced built-in security features
  • No additional hardware required
  • Low power consumption
  • Low latency
  • Expansive Bluetooth device ecosystem

Bluetooth Channel Sounding in action

  • Smart Locks
  • Personal tags
  • Real-time asset tracking
  • Car locks

Featured products for design