Hi there. I am hoping someone can assist me with a LoRa issue.
I am using a MKR 1310 as a LoRa receiver. It works great when I have one transmitter powered on. If I power on more than 1 transmitter, the receiver will pick up both for a bit, but then seems to favor one over the other and 95% of the incoming data is from a single transmitter.
I am using the Lora.h library.
I do use a syncword to limit received data, a bandwidth = 250, SF=9, CR=6 and CRC enabled. If at any time I turn off one of the transmitters, the other will be received as normal. It does not seem to matter how many transmitters I turn on, one (and usually the same one) will become dominant with very little data actually being read at the receiver for the others. I know they are sending because the occasional data string comes in.
The data does have checks to label which transmitter it is from, but if the data is never received, this isn't really necessary.
It does not seem to matter what the SNR and RSSI are. Transmitters with lower SNR can be dominant or it could be higher.
I have increased the time between transmissions but it has changed nothing in relation to this issue. I have decreased power, no change.
I have tried a couple of detection loops including looking for LoRa.available() to read the string as well as the OnReceive and they both seem to give the same results. I am wondering if it is seeing all the data coming in from multiple transmitters as one, but only reading the first arrived data and discarding the rest from other detectors. Data is a comma separated string of 5 values followed by a LF. I am reading to the LF.
Any thoughts are appreciated.