RE: Is there a predictable connection method for multiple central and multiple peripherals?

Kenneth — Mon, 24 Apr 2023 13:08:10 GMT

Hello,

RSSI is not an accurate measurement of range, you may get some indication that it's close by, but if there are several devices close by you will not be able to accurately identify which is closest no. You can try to measure RSSI over time, so build confidence it's the device that is closest.

I don't see any easy way to solve this, but a few things to consider:

- Are you sure you need to dynamically always connect to the device that is closest? What is most common is that the two peers establish a bond, this is a one-time operation, and then later the two peers can re-connect independant of the distance between the two.

- You can use some kind of user interface, where the central and peripheral will display the same random pattern on some leds, and if you see that it's the wrong peripheral you can just try to connect to the next peripheral.

- Using NFC is possible, but then you need a NFC reader in the central, this must be a third party IC, since we only provide NFC tag internally.

- Look into using distance measurement library:
https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/libraries/others/dm.html#distance-measurement

Best regards,
Kenneth