Integrator here, usually on the PLC side so LoRaWAN is new-ish for me.
Our manufacturing site has about 30 LoRaWAN sensors (temperature, door contacts, a few tank levels) on Hermetry’s network server, one Basics Station gateway on the main building roof. 26 work fine. Four that sit behind a steel-clad warehouse at the far end of the yard either never join or join once and then go silent.
A colleague who does home automation said this is why mesh exists, every node relays for its neighbours and you never get dead corners. Which made me wonder why LoRaWAN is a star at all. Is there a relay or repeater option in Hermetry I’m missing, or something I can set on those four?
Zigbee at home meshes fine for me, every mains-powered plug becomes a router. Never had a dead corner since.
Can’t you just put the antenna higher?
Antenna is already on a 3 m mast. Frames log for the far ones shows two of them do get heard:
JoinRequest DevEUI 70B3D5...1A2 DR0 RSSI -121 SNR -14.5
JoinRequest DevEUI 70B3D5...1A2 DR0 RSSI -122 SNR -15.0
(no uplinks after)The other two don’t show up at all.
Isn’t there a relay feature? I’m sure I saw a gateway status called Pending somewhere in the gateway list.
I did a module on this last term, and then spent a summer placing gateways at a dairy, so here goes.
Mesh works at home because the routers are mains powered and always listening. LoRaWAN end devices are battery sensors that sleep almost all the time and only open short receive windows after they send. A sleeping node can’t forward anyone else’s traffic, so the network is a star of stars instead: every gateway in range hears every uplink, and the network server throws away the duplicates. More gateways means more coverage, and on Hermetry a device message is stored once no matter how many gateways heard it.
James, the Pending status is real, it’s for relay gateways that were seen but not accepted yet. A relay is still one more box to place and power though, and for four sensors behind one warehouse a second gateway is simpler.
Your two heard devices are joining at SF12 with SNR around -15, which is at the edge. The join request gets through, but the join accept has to come back to the device 5 s later in RX1, or 6 s in RX2 at 869.525 MHz (DR0), and at that margin the downlink often doesn’t make it. The other two probably never reach the gateway at all.
Put a second gateway on the warehouse itself, ideally on the side facing those sensors. It can be another Basics Station gateway or a licensed router with a LoRa radio. Both register to the same network server and the sensors just use whichever hears them best.
Relays and the other ways to extend coverage: Local mode and relays
Does adding a second gateway change anything for duty cycle? We have a lot of confirmed uplinks at our sites.
Got a second Basics Station on the warehouse gable with PoE from the dock office switch. All four joined within the hour, and the two that never showed up are at DR3 now. Thanks Aoife.
cmiller, from what I read the duty cycle ledger is per gateway, so a second gateway gives you more downlink budget, not less. Confirmed uplinks still eat it though, we switched our door sensors to unconfirmed while we were at it.
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