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Help with understanding how LoRa works

Hi there,

So I am trying to wrap my head around one particular thing with using the RFM95 modules. In most arduino code I have not seen an address set like when using NRF24 modules. I see there is a syncword function that seems to act like an address. So what I would like to know is can anyone pick up packets that I am sending if I do not use syncword. And vice versa can I pick up someone else’s packets. I would be using my LoRa modules for peer to peer and not connect it to a LoRaWan network.

Do not think of syncwords as a mechanism for blocking or preventing receptions of transmission as in some values they can be leaky.

If you want to prevent your sent packets being received (and understood) by others, then encrypt the packets.

Thank you. I will take a look at encrypting packets.

Sorry I should have been more clear in my question. It does not matter to me if my packets are picked up by someone else (sensor data is from a BME280), I just don’t want to have someone else’s packets being picked up.

Say my neighbor was using a LoRa module to transmit without encryption and I was using a receiver to receive sensor data from my own sensor. Would I receive both mine and my neighbors packets?

If the two transmitters were using the same settings, then yes you would receive both packets.

All you need to do is send an ID number, say a uint32_t, which is a unique ID as part of your packets. If the received packets dont have that ID number in them then ignore them. The chance of the rogue transmitter having the exact same 4 byte sequence in it is remote.