[SOLVED] Can I use those channels which are not adjacent in LoRaWAN?

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Hi,everyone:
I want to know If I can set my gateway(SX1301) to use those channels which are not adjacent in LoRaWAN.
For example, in CN470-510MHz Band, there are 96 uplink channels(channel 0 ~ channel 95),Channel Index 6 to 38 and 45 to 77 are mainly used by China Electric Power which means that I can only use the channel 0~5, channel 39~44, channel 78~95. Can I set my gateway’s eight channels using channel 0~2, channel 39~41, channel 80~81?
Why I have the question? Because from the datasheet of SX1301, I see that the eight channels of SX1301 can be set respectively, which means that I can use any available channel. But some manufacturers told me that I better use eight channels which are adjacent ,for exmaple channel 80~87 and should not use eight channels that are not adjacent because the SX1255 may not support that and a lot of algorithms in LoRaWAN require eight adjacent channels. Is that true?

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Hi @David2044, the Semtech SX1301 is a base-band processor chip. In a typical EU setup the LoRaWAN concentrator uses two Semtech SX1257 RF chips as the radio “front-end” transceivers. Each SX1257 can scan 1MHz of RF spectrum. The SX1257 is designed to operate between 862MHz and 960MHz.

In the normal EU configuration radio_0 is configured for a centre-freq at 867.5MHz and radio_1 is configured for a centre-freq at 868.5MHz.

So, in the EU, all channels are completely inside one of the two 1MHz bands.
The default EU configuration has the two 1Mhz bands adjacent but you could [technically] operate with radio_0 centred on 863MHz and radio_1 centred on 959MHz.

The different RF transceiver hardware for the CN bands may have different capabilities. The best way forward is to study the appropriate LoRaWAN concentrator boards for the CN bands and then study the Semtech RF transceiver chips - how many are there and what bandwidth can they cover?

3 Likes
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Indeed. You should be able to use two distinct channel groups of (up to) four channels each, provided they are within range of the front end radio ICs and surrounding RF circuitry.

But you won’t be able to use three distinct groups, for that you would need a second gateway or at least a second concentrator card.

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Thanks, I got it. Thank you so much

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Thanks, thanks your guys, you are so nice! I finally figure it out!