2 years, 10 months ago.

LORA specification.

hello, well i'm trying to Gain a basic understanding of what Long Range (LoRa) is, and how LORAWAN communications work, which will allow me to build a LoRa software( i hope) . i was reading about : Creation / Modification of a Channel (NewChannelReq, NewChannelAns) and i pumped into this lignes in the spec documentation, i didnt really udrestand it, DrRange = 0x77 means that only 50 kbps GFSK is allowed on a channel and 6 DrRange = 0x50 means that DR0 / 125 kHz to DR5 / 125 kHz are supported.

i mean how am i soppose to know how many channels should be allowed besides the default ones. thanx.

best regards

Question relating to:

Semtech's Wireless, Sensing and Timing product group

1 Answer

2 years, 10 months ago.

I'm not really sure what your question is exactly, and it also depends on your location. LoRaWAN uses (in Europe) 3x 125 MHz default channels at 868.1, 868.3 and 868.5 MHz. When the device initiates a JOIN (over one of these channels) the network can instruct the device to use five additional 125 MHz channels, a high-bandwidth LoRa channel or an FSK channel; all between 867 and 869 MHz. But I don't think I've seen devices / networks use the high-bandwidth or the FSK channels.

Regardless, the network server will send the list of additional channels in the JoinAccept request, see "7.1.4 EU863-870 JoinAccept CFList" in the LoRaWAN spec.

Accepted Answer

My location is in Tunisia, Noth Africa. thanx alot anyway that clarifies a bit more the way joing channels is happening. i was wondering, i'm trying to built my soft using SX1272 and an STM32f4 as a hardware, i have being looking for some examples just to have a look on the way the includes are added and the MAC libraries are integrated through the soft and what do they contain exactly...i have found some on this ARMmbed platform, i didn't really get. So do think this this is possible(building my LoRa software) with that hardware ? and do u have any kind sourse that can help me through this project?

tank you, best regards.

posted by ben taher amine 13 Apr 2017

I'd suggest to use LMiC as a base. It already contains a reference LoRaWAN MAC layer implementation and drivers for SX1272 and SX1276 and is mbed compatible.

posted by Jan Jongboom 01 May 2017