Hey there,
Iam using the LoRa physical Layer to communicate between 2 MCUs with a Semtech SX1261 chip.
They are communicating point-to-point and iam not using any LoRa-Wan services at all.
iam just using the modulation
I understodd that LoRaWAN uses frequencies in the ISM Band and that many people have to share theese free reccources (Dutycycles)
I live in Germany and the LoRa allocated frequency plan here is called EU863-870.
there are 8 LoRa channels listed, most of them with SF7-12 and BW =125khz
(https://www.thethingsnetwork.org/docs/lorawan/frequency-plans.html)
the Semtech Chip allows it to send packets with the SF5-12 and BW from 7.8khz to 500khz
Iam wondering if iam allowed to send packages with a SF ouf of the Frequency plan?
for exampe with SF5 and BW = 500khz? ( to reduce my ToA to a minimum)
do i have to care about the allowes duty cycles then?
Iam using the LoRa physical Layer to communicate between 2 MCUs with a Semtech SX1261 chip.
They are communicating point-to-point and iam not using any LoRa-Wan services at all.
Then this is a qustion outside of the scope of the TTN forum really.
What ever transmissions you are using you still have to follow ISM rules for the country you are in and the frequencies you are using. In some cases there are relaxed duty cycle rules depending on the bandwidths in use, but I beleive that may be on a country by country basis rather than universal.
Hi @mct, to help you get properly away from TTN LoRaWAN RF spectrum and prevent interference, I’m going to go outside the normal forum TTN/LoRaWAN scope.
The EU standard ERC REC 70-03, May 2017, offers you an option safely away from the standard EU LoRaWAN channel configuration. Table 1, h1.7 offers 869.7-870.0MHz (300KHz b/w) at 5mW ERP with no duty cycle, just LBT.
See also the Semtech AN1200.23 & .24 documents that are aware of this frquency and offer a “Mode 3” to correctly configure the relevant registers for this freq with 250KHz.
I have used this frequency band successfully with RAK modules (SX1272 chips) for P2P LoRa using the following at command; at+rf_config=869850000,12,1,4,8,7 (freq, SF12, 250KHz, 4/8 coding, preamble, power).
i thought i would disturb other LoRaWAN users when i send at a unspecified channel.
But the Spreading factors are orthogonal ot each other and that eliminates that problem.
