Title: Best Method for Accurate BLE Distance Measurement Between Two Devices

[Usha]

Description:

Hello,

I want to measure the distance between two BLE devices with high accuracy. I have already tried using nRF52840 modules, but the results are not very precise.

Questions:

1. What is the best approach for accurate BLE-based distance measurement?
2. Does Nordic provide any recommended algorithms or libraries for this purpose?
3. Would nRF Distance Measurement (nRF DM) with MCPD or RTT be suitable for achieving better accuracy?
4. Are there any specific hardware configurations or external components that can improve the accuracy?

I would appreciate any guidance or recommendations. Thank you! 

[Simonr]

The documentation is rather brief, but it is basiacally explaining what's necessary. You need to compensate the zero-calibration offset and by performing a manually calibration. To determine the offset, place the devices at a known reference distance (we recommend 60cm) from antenna to antenna. Then collect a batch of measurement data. The difference between the average measurement and the actual distance can then be used as an offset. Whether you implement this offset to be deducted/added in the calculation on either of the devices is entirely up to you. 

Best regards,

Simon