Interferences from neighbour nodes

Hello. I have one node testing in a client facility and I loss some uplinks. I observe watching the gateway frame log that the losses are when other nodes from other networks are transmitting at the same time. I can see several frames from the other nodes instead of one of my node.
My node is sending in SF8 or SF9. The other nodes are SF12.

My Gateway is a Dragino DLOS8.
That losses supposes delay on the process information and it wouldn’t be acceptable for the client.

I see that my device has approximately in SF8: RSSI: -39 SNR: 7.5. In SF9: RSSI:-114 SNR: -7
The other devices in SF12 RSSI: -67 SNR: 11.8.
Three tests in the morning were ok. One test in the afternoon was not Ok. In different distances from the Gateway.
What could I do?
The only idea I have is to modify ADR algorithm and fix the nodes to send to the maximum power inside the DR removing the tx power adjust. I don’t know If that will make continuous DR changes.

My node is sending in SF8 or SF9. The other nodes are SF12.

With LoRa, packets using different spreading factors are orthogonal, meaning that they are invisible to each other: as mentioned earlier, they simply appear as noise to one another. Therefore, two packets that arrive at the same time on the same receive channel at different spreading factors will not collide and, both will be demodulated by the gateway modem chip. However, two packets with the *same* spreading factor arriving at the same time on the same channel **might** result in a collision. However if one of the two packets is stronger by six dB, it will survive.

more info:LoRa and LoRaWAN: Technical overview | DEVELOPER PORTAL

That losses supposes delay on the process information and it wouldn’t be acceptable for the client.

Don’t use Lora if the lost of some uplinks are a big problem.

Do some filter in gateway. Filter by DevEUI or NetID … it may help

Dont send uplink every 10sec at SF8 and SF9 and dont send “Confirmed Data Up” … that will also help

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