[SX1280] Low SNR on diversity receiver hardware


I have been testing a number of sx1280 diversity receivers for the ExpressLRS project. Hardware has 2 sx1280 transceivers in very close proximity e.g. within 10mm. Normal operation is to set both transceivers in rx mode on the same frequency to receive lora or flrc packets.

On some hardware when receiving lora packets with both transceivers on the same frequency, the SNR can be seen to decrease! and when receiving flrc packets there are a large number of missed packets. But if the transceivers are receiving packet on different frequencies the SNR is high and packet reception normal. Each radio can also be used individually and performs perfectly.

It appears as though there is noise/interference between the transceivers when receiving and set to the same frequency.

Is Semtech able to provide a reference design for minimising interference between 2 sx1280 transceivers in close proximity?

Any help would be greatly appreciated.

Jye -

1 Like