I’ve been experimenting with two WiFi LoRa 32 V2.1’s (915Mhz - AU915 band) with the example “LoRaSetSpread” programs. The devices are fitted with the Heltec spring antennas and enclosed in the little plastic cases exactly like in the Heltec web page - ie https://heltec.org/project/wifi-lora-32/
The max range I seem to be able to achieve in the open air is about 300 metres with a spreading factor of 10. Probably not much better than WiFi. What should I expect?
I have tested a commercial product recently, also with only inbuilt antennas, and I was able to achieve 10 times this range.
There are a couple of anomalies however.
1 - The RSSI degrades to -120 or so when reception cuts out which tallies with what I know about LoRa, but the SNR remains around 6ish. If the Heltec is computing SNR in the normal LoRa way, this would mean the signal is 4 times the noise floor which should be plenty, but this seems at odds with the RSSI. Some other LoRa devices I have played with recently work down to a SNR of -17 or so, ie where the signal is about 1/50th of the noise floor. Maybe Heltec is measuring SNR differently?
2- I have also played with the spreading factor, but this doesn’t seem to greatly increase the range as expect. In fact, when I set a spreading factor of 12, the devices do not appear to communicate at all even when sitting along side one another.
Any suggestions welcome.