Echo on Rx when sending proprietary LoRa frames

ChirpStack Gateway Bridge
1

Hi all,

First thing first, thanks for this project. I’am using a Raspberry + RAK831 since some time now. GREAT piece of software.

Shortly, I’am using the projet to construct a bridge between LoRaWan and our proprietary protocol (over LoRa).

Every thing seems OK, but when I send my proprietary frame to: “gateway/my_gateway_ID/tx” I receive the frame sent on “gateway/my_gateway_ID/rx”.

Is there a way to avoid echo ?

Thanks,
BR.

2

Have you set polarizationInversion: true? See also https://www.loraserver.io/lora-gateway-bridge/payloads/commands/.

3

Thanks for your fast reply.

I’am using the LoRaServer 2.0.2, and here is the config I use :

“{ “token”: 65535, “phyPayload”: “”+encoded[:-1]+”", “txInfo”: { “codeRate”: “4/5”, “dataRate”: { “bandwidth”: 125, “modulation”: “LORA”, “spreadFactor”: 10 }, “frequency”: 868100000, “immediately”: true, “mac”: “aa555a0000000101”, “power”: 14, “iPol”: false } }"

I tried to switch with “iPol : true”, but my receiver is configurated with :
#define LORA_IQ_INVERSION_ON false
Then it’s not receiving the frame.

Any suggestion ?
Thanks,

4

I can’t support proprietary implementations, but in general when devices are sending to gateways the iPol is set to false and when gateways are sending to devices the iPol is set to true exactly to avoid your issue :slight_smile: (by default, gateways will not receive frames with iPol set to true).

5

Hi brocaar,

My fault :slight_smile:
As I’am using a proprietary single channel gateway, that was not an issue.
Everything fine now !

Thanks,
BR