I have just purchased a RAK7258 Indoor gateway, I have Pycom Lopy4 connecting to the gateway using OTAA. Uplink and Downlink work perfectly with the TTN, except it won’t work beyond 80 meters.
I’m using the indoor antenna it came with, I have tested the node with a Pycom Nano gateway and I can get significantly longer distances. I’m happy to get a new Full Wave Antenna, but I fear there’s a bigger issue with the gateway setup. I’ve checked the obvious connections with the Indoor Antenna and tried the Pycom Antenna on Gateway with no improvement
I’m located in Sydney using AU915, below are some logs from 40 meters (Gateway to Node)
Gateway Firmware - 1.1.0053_Release r188
Network & Power: POE
It doesn’t really make any sense that you’d be getting -70 for RSSI and excellent SNR at 40 meters, but total failure at 80.
Radio just doesn’t work like that, and even if it were failing, there’d be a distance where you occasionally got weak signals - you should see things below -110 RSSI with SNR at -10 or worse, being actually received.
Also worth noting that your node seems to be using only fairly high data rates which are implicitly short range modes, though they go further than 80 meters.
If you suspect something wrong with the gateway, two definite things to check are that the antenna connector is actually connected to the card inside, and that the card inside is a 915 MHz (and not 868 MHz) model.
Also try it with a decent DC power adapter to rule out any noise being brought in from the POE supply.
Thanks Chris for you prompt help. I now understand more about the issue.
If I authenticate the node within 20 meters of the node, then I walk down the street with the node I can go 300 meters and it still works. The problem appears to be authentication, with either OTAA or ABP from a distance/low RSSI (<-80). The Antenna connection and Chip Freq look fine for Australia, changed to a DC supply as well
It’s not quite “authentication” and in fact ABP does not require a round trip at all.
However, it sounds as if perhaps your node is bad at receiving. This could point to node side issues like a bad antenna connection there, RF network for the wrong band, or a noisy node power supply. It is possible to get the RSSI and SNR from the node radio chip as well, though your node firmware might not be doing so.
When you say “your node seems to be using only fairly high data rates” what figures are you referring to? the coding rate (CR)?
Your logged transmissions are all at the fast spreading rate SF7 or the even faster one SF6. The higher the number the slower the data, and the longer the range. Typically in the US a node would start at SF10 or at least ramp to that when nothing else was working, in Europe SF12 is possible (with packets that are over a second long!). You can consult the LoRaWAN regional parameters document to find out what conventions are applicable to you. Also keep in mind that there are two sets of options in Australia with different conventions, its vaguely possible that some mismatch or hybrid mixup of the two could be at fault.
A system that gives up while only trying SF7 is not using LoRa very strategically, though you should be able to easily get more than 80 meters of free space range at SF7 and low power level.
You can use OTAA join mode and turn on the ADR function in the webpage “LoRa Network Server–>General” and set the maximum and minimum rates.At the same time, the transmission power can be modified. The maximum tr