Make end node forwarding node


(Gyh) #1

Hello.
I am making end node forwarding node (end node).
My system model is like this.
End device, forwarding device, gateway.

  1. End device send message to forwarding device and gateway
  2. forwarding device forward the message from end device to gateway

In the LoRaWAN, it is not available. The end devices cannot receive other end devices messages and gateway cannot other gateways messages because of iqInverted value 1) End device Rx: On, Tx: Off 2) GW Rx: Off, Tx: On.
So i try to make forwarding node as Rx: Off, Tx: Off

So my question is that

  1. Is it possible to make forwarding node as i change the Radio iqInverted value?

  2. If i make forwarding node, is it needed to make new Class definition such as Class A, B ??

  3. I want to know the how the modulation is proceed using I/Q and CSS modulation. I cannot understand how the message is modulated.

Thanks in advance


(Arjan) #2

When using LoRaWAN, inverted IQ is not going to be your biggest problem.

True mesh networks between LoRaWAN nodes are not possible, not so much due to technical limitations but above all due to the LoRaWAN protocol: Class A nodes are simply only listening after they transmitted themselves, and if a Class C node is listening all the time then that’s just on a single frequency. See also Relaying IoT messages using mesh networks.

Using a repeater/relay gateway will not get you a compliant LoRaWAN network either, as timing for downlinks is very critical; once a true gateway is sending a downlink in RX2, there is no way for some repeater to re-transmit that in time for an actual Class A node, which is only listening at specific intervals. That includes downlinks for OTAA Join Accepts. See Lorawan repeater and Repeater behaviour.

Note that in the latter, a post explains a bit about bare LoRa (rather than LoRaWAN), which are not to be confused:

Of course, The Things Network is about LoRaWAN.