Hello!
I have a problem with endless JoinRequest/JoinAccept loop between nodes and gateway.
Gateway: Mikrotik LtAP LR8 LTE kit (EU868)
Nodes: Dragino LSN50-V2 (EU868)
Nodes are about 12 meters from the gateway but I also tried lower distances like 8m, 4m, 2m and even putting them at the gateway.
I use Chirpstack but the problem is with the devices, not the environment.
So I really hope to find some help or guidance here 
Node communicates with the gateway (it’s visible in gateway’s console) but in most cases it does not join the network. I would say that it happens hardly ever.
This is an example of a successful join:
LSN50 Device
Image Version: v1.8.1
LoRaWan Stack: DR-LWS-007
Frequency Band: EU868
DevEui= xx xx xx xx xx xx xx xx
Please use AT+DEBUG to see debug info
***** UpLinkCounter= 0 *****
TX on freq 868.500 MHz at DR 5
txDone
RX on freq 868.500 MHz at DR 5
rxTimeOut
RX on freq 869.525 MHz at DR 0
rxTimeOut
***** UpLinkCounter= 0 *****
TX on freq 868.300 MHz at DR 5
txDone
RX on freq 868.300 MHz at DR 5
rxTimeOut
RX on freq 869.525 MHz at DR 0
rxTimeOut
***** UpLinkCounter= 0 *****
TX on freq 868.500 MHz at DR 5
txDone
RX on freq 868.500 MHz at DR 5
rxDone
Rssi= -104
JOINED
But usually it’s an endless loop like this:
LSN50 Device
Image Version: v1.8.1
LoRaWan Stack: DR-LWS-007
Frequency Band: EU868
DevEui= xx xx xx xx xx xx xx xx
Please use AT+DEBUG to see debug info
***** UpLinkCounter= 0 *****
TX on freq 868.100 MHz at DR 5
txDone
RX on freq 868.100 MHz at DR 5
rxTimeOut
RX on freq 869.525 MHz at DR 0
rxTimeOut
***** UpLinkCounter= 0 *****
TX on freq 868.100 MHz at DR 5
txDone
RX on freq 868.100 MHz at DR 5
rxTimeOut
RX on freq 869.525 MHz at DR 0
rxTimeOut
***** UpLinkCounter= 0 *****
TX on freq 868.300 MHz at DR 5
txDone
RX on freq 868.300 MHz at DR 5
rxTimeOut
RX on freq 869.525 MHz at DR 0
rxTimeOut
***** UpLinkCounter= 0 *****
TX on freq 868.500 MHz at DR 4
txDone
RX on freq 868.500 MHz at DR 4
rxTimeOut
RX on freq 869.525 MHz at DR 0
rxTimeOut
***** UpLinkCounter= 0 *****
TX on freq 868.100 MHz at DR 4
txDone
RX on freq 868.100 MHz at DR 4
rxTimeOut
RX on freq 869.525 MHz at DR 0
rxTimeOut
***** UpLinkCounter= 0 *****
TX on freq 868.300 MHz at DR 4
txDone
RX on freq 868.300 MHz at DR 4
rxTimeOut
RX on freq 869.525 MHz at DR 0
rxTimeOut
***** UpLinkCounter= 0 *****
TX on freq 868.100 MHz at DR 3
txDone
RX on freq 868.100 MHz at DR 3
rxTimeOut
RX on freq 869.525 MHz at DR 0
rxTimeOut
***** UpLinkCounter= 0 *****
TX on freq 868.500 MHz at DR 3
txDone
RX on freq 868.500 MHz at DR 3
rxTimeOut
RX on freq 869.525 MHz at DR 0
rxTimeOut
***** UpLinkCounter= 0 *****
TX on freq 868.500 MHz at DR 3
txDone
RX on freq 868.500 MHz at DR 3
rxTimeOut
RX on freq 869.525 MHz at DR 0
rxTimeOut
***** UpLinkCounter= 0 *****
TX on freq 868.500 MHz at DR 2
txDone
RX on freq 868.500 MHz at DR 2
rxTimeOut
RX on freq 869.525 MHz at DR 0
rxTimeOut
***** UpLinkCounter= 0 *****
TX on freq 868.300 MHz at DR 2
txDone
RX on freq 868.300 MHz at DR 2
rxTimeOut
RX on freq 869.525 MHz at DR 0
rxTimeOut
***** UpLinkCounter= 0 *****
TX on freq 868.500 MHz at DR 2
txDone
RX on freq 868.500 MHz at DR 2
rxTimeOut
RX on freq 869.525 MHz at DR 0
rxTimeOut
***** UpLinkCounter= 0 *****
TX on freq 868.500 MHz at DR 1
txDone
RX on freq 868.500 MHz at DR 1
rxTimeOut
RX on freq 869.525 MHz at DR 0
rxTimeOut
***** UpLinkCounter= 0 *****
TX on freq 868.500 MHz at DR 1
txDone
RX on freq 868.500 MHz at DR 1
rxTimeOut
RX on freq 869.525 MHz at DR 0
rxTimeOut
***** UpLinkCounter= 0 *****
TX on freq 868.300 MHz at DR 1
txDone
RX on freq 868.300 MHz at DR 1
rxTimeOut
RX on freq 869.525 MHz at DR 0
rxTimeOut
***** UpLinkCounter= 0 *****
TX on freq 868.300 MHz at DR 0
txDone
RX on freq 868.300 MHz at DR 0
rxTimeOut
RX on freq 869.525 MHz at DR 0
rxTimeOut
***** UpLinkCounter= 0 *****
TX on freq 868.100 MHz at DR 0
txDone
RX on freq 868.100 MHz at DR 0
rxTimeOut
RX on freq 869.525 MHz at DR 0
rxTimeOut
...
Here is node config:
AT+ADR=1
AT+TXP=0
AT+DR=3
AT+DCS=0
AT+PNM=1
AT+RX2FQ=869525000
AT+RX2DR=0
AT+RX1DL=1000
AT+RX2DL=2000
AT+JN1DL=5000
AT+JN2DL=6000
AT+NJM=1
AT+NWKID=00 00 00 00
AT+FCU=0
AT+FCD=0
AT+CLASS=A
AT+NJS=0
AT+RECVB=0:
AT+RECV=0:
AT+RJTDC=20
AT+RPL=0
AT+VER=v1.8.1 EU868
AT+CFM=0,7,0
AT+CFS=0
AT+SNR=0
AT+RSSI=0
AT+TDC=60000
AT+PORT=2
AT+RX1WTO=9
AT+RX2WTO=6
AT+DECRYPT=0
AT+MOD=1
AT+INTMOD1=2
AT+INTMOD2=2
AT+INTMOD3=2
AT+WEIGAP=400.0
AT+5VT=500
AT+CHS=0
AT+DDETECT=1,1440,2880
AT+SETMAXNBTRANS=1,0
AT+DISFCNTCHECK=0
AT+DISMACANS=0
Gateway config screen:
I was told that signal is very bad and it might be due to the interferences in my area (other LoRaWAN or gsm devices).
Here’s gateway traffic with radio params:
Here’s channels info:
That’s why I tried excluding possible interferences by running the devices in the underground garage. I’m aware that there is no gsm signal there but still nodes should join the gateway, right?
Garage is a closed box, its dimensions are about 5 x 3.5 meters.
Nodes were 2-3 meters from the gateway, I also tried putting them just at it.
There was no successful join from any node.
Here’s the traffic from the garage with signal params:
What am I missing? Can it be something wrong with gateway’s internal antenna? Should I try using external antenna?
I will provide any details needed.