TTIG and ADR

I’ve got some of the tabs sensors in both my office (TTIG) and home (IMST and Pi) and noticed that the office sensors are now sitting at SF12. They only see the TTIG and the TTIG often reconnects as it doesn’t receive a packet every 30 seconds so I see most of the packets as retries.

What this seems to mean is that the TTIG misses most of the downlinknslots as it’s too late for the device while it reconnects to the network. This seems like a design flaw and probably results in breaking the fair use now the sensors are sitting next to a gateway but at SF12.

Any thoughts on this and whether newer firmware might fix it?

maybe the node isn’t receiving always the downlink so it will try until reaches sf12 ?
'what if ’ you bring node and gw closer to test ?

There is less than a metre between them - all being used in an office environment. I’ve tested the ping times over the network too and seeing about 50ms so shouldn’t be a problem there.

Less than a meter is far to close. That will result in crosstalk between channels. Make sure to keep at least 3 meters between a node and a gateway.

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I got my estimates a bit wrong there as I’d moved them a few times and they were about 3m away.

Bringing a different model gateway nearby or moving the sensors home where I have an IMST concentrator and Pi brings them back to SF7 using ADR. Likewise, using my ttnmapper board set to 20 second intervals nearby also allows them to lower the data rate.

I can only conclude that the TTIG doesn’t do well with ADR if it doesn’t get a packet from anything within 30 seconds. This is because it seems to do a store and forward of the received packet while it reconnects to TTN and thus will miss the downlink slot.

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