Weird LoRawan behavior observed with spectrum analyzer

Products & Technology Raspberry Pi
#1

Today I have did some testing: Node: FiPy ABP transmitting a byte, blink immediately led for debugging after sending, listening for receiving, repeat every 10 seconds.

Gateway: RisingHF.

Both connected end to end with a coaxial wire (no antenna) and the wire also connected to an spectrum analyzer for sniffing with a T connector.



What I observed is strange:

  1. There are some 8 seconds between the node blinks (sending) and some activity is observed on Spectrum Analyzer.
  2. There are some 10 seconds between the activity observed on Spectrum Analyzer and the gateway shows that the package was received on internal web-interface.
  3. Even with direct connection through the coaxial wire, there are wide values of RSSI from -6 to -117.
  4. Even that, there are some packages that never are received (or shown as received) on gateway web interface.



    Help!
#2

Hello!



I was told in other others forum (with much more manufacture’s support) that SeeedStudio Gateway with RisingHF RHF0M301-915 is not able to use all 64 channels described in LoRaWAN specification. Just 8 of them. This is called Hybrid mode.



So I need to set up my nodes on same sub-channel that the Gateway is listening to. My question is what is the sub-set of channels that the Gateway is listening to.



With best regards



Sebastian Barillaro

#3

Hi Sebastian, let me check with designer and keep you posted. thanks.



Seeed techsupport team

Bill

#4

The answer to my own question is: It depends on global_config.json

Default configuration use the first subset of US915



Thank you anyway