Channel Activity Detection (CAD) / CSMA-CA

[XinyingKilpi-Chen]

I need to solve the problem when many Shelly LoRa devices send message the same time, how can I avoid collision to ensure the package successfully delivered.

Is there a 'cad' parameter or someway that can check the channel status and tell me the status, so I can react accordingly.

function sendMessage(msg) {
Shelly.call(
'Lora.SendBytes',
{
id: 100,
data: btoa(msg),
cad: true,
},
function (data, err, errmsg) {
if (err) {
console.log('Error:', err, errmsg);
return;
}
}
);
}