nRF52840 reconnection distance

[kimhh]

I conducted a BLE test using two nRF52840 Dongles. Since I used Dongles, I based my code on the usbd example from the sample programs. During testing, the connection between the two Dongles dropped at a distance of approximately 50 meters, but reconnection was only possible at around 10 meters. This result was consistent across multiple tests. Additionally, changing PHY and TX Power did not make any difference.

Why is the reconnection distance significantly shorter than the disconnection distance?

[Elfving]

Hi again guys,

kimhh said:

Do you have any data on BLE disconnection and reconnection distance testing using a Dongle in any environments? If so, could you provide it?

Not that I know of. Like I said, dongles (or DKs for that matter) aren't made for this purpose, but I guess if we had data on this it would presumably be for DKs. 

kimhh said:

Additionally, to rule out potential noise issues, I conducted the test in a shielded environment, but the problem persisted.

I see. Then I would assume it's SW related. Some difference in distance here would make sense, as for a connection you have slave latency and supervision timeout, which lets you withstand a few packet losses before having to lose the connection. 

A sniffer trace and/or would help a lot, to help us see what caused the two to lose the connection.

Regards and have a good week-end,

Elfving