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Unable to pair through Sync Word

Hi,
I have 4 LoRa Sx1278 modules, I have set the sync word of the 2 module as 0x12 and the remaining two as 0x24. According to the datasheet they should not interfere with each other but yet they are interfering with each other. I have also tried to change the sync word but yet the results are the same. In the following link the sync words were too different yet they interfered. https://github.com/sandeepmistry/arduino-LoRa/issues/16

Please help.

Thanks and Regards.
Maaz Shaikh
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Hi,

Having a different Sync Word (just like for another radio, for instance a 15.4g FSK one with different SFD), does NOT prevent interference whatsoever. It is just a matter of not continuing on reception (and the usage of the resource) if the Sync Word doesn't match.
In other words, if the Sync Word fails, the radio will restart it research of a preamble.

You should observe however, that if you try and receive packets with a 0x34 receiver, whilst transmitting 0x12 packets, that most of them will be ignored.

Best regards
Thanks for your reply, can please let me know how I can pair LoRa modules so that I can ignore all the rest of the signals. I just want a simple pairing method
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Hello,

For this, the Sync Word wil only give you about 90% isolation. You should use, at the beginning of a PHY payload (MAC header), a concept such as "Network ID" or "Device ID". LoRaWAN uses a short 4 byte DevAddr, for instance

Best regards