Isolated Network Issue

[kadirozdinc]

Hi sandeep,

I am planning to create some lora networks which are isolated from each other, I want for these different networks not to affect each other. There is an examle of syncword but this technique is limited with 255, I need more of them. How should I need to set up these isolated network.

(For examle, One lora network includes 1 sender and 4 receiver as duplex mode.)

[IoTThinks]

Sync Word won't guarantee 100% of isolation. There is still interference with Sync Word.
You can use different frequencies 920, 921, 922... => Zero interference.

Why do you need more than 255 isolated networks?

[kadirozdinc]

I use cheap FPC antenna from china right now. Since I dont have vna device, I cannot check if its in the right range. Lets say my antenna is out of range, does it cause interference ?

LoRa covers very wide range of area and many users might prefer to use LoRa. I am wondering how these users can isolate their networks to prevent interference ?

[IoTThinks]

Something is really incorrect at your side.
Double check everything again.

[kadirozdinc]

I change bandwidth to 250khz after 125khz problem solved for now. To be able to isolate networks, can preambleLength parameter be used ? What does preambleLength parameter do ?

[IoTThinks]

Preample is to know where is the beginning of an LoRa packet.

[kadirozdinc]

Yes it is ,why do we need to use it ? I have found an explanation about it

Preamble: used to keep the receiver synchronized with the incoming data stream. The default is 12 symbol lengths, and 8 symbol lengths are used in LoRaWAN. The preamble length is a variable that can be set by programming, so the length of the preamble can be extended. The length of the preamble of the receiver should be the same as that of the transmitter. If the preamble length is unknown or may change, the receiver’s preamble length should be set to the maximum value. Address filtering can be performed by setting the preamble value to achieve packet communication.

If so, It seems I can use it for address filtering