HTCC-AB02S, LoRa lower bandwidth than 125khz

#1

Good evening, my coding abilities are limited so apologize in advance.

So I setup two Arduino’s last year with a Semtech LoRa chip to send and receive. Bought the CubeCell as it came fully equipped with a GPS etc rather than having to assemble it myself.

So I managed to get it to send a GPS coordinates to my existing receiver but I seem to be limited to no less than 125Khz bandwidth by LoRaWAN - I would like to be using 62.5E3 to match by existing and I don’t want to use WAN.

Any help would be appreciated! or pointing in the right direction.

Cheers, James

#2

I didn’t catch your meaning. Do you want to use Lora ad hoc network?

#3

Morning, yes sorry. Ad hoc rather than via a WAN (which does limit the available bandwidth).

Looking through the files radio.c (asr6501_lrwan) which is included in the factory example? for bandwidth it expects 0 for 125Khz, 1 = 250 and 2 = 500 Khz and there seems to be no way of setting it to your own bandwidth outside (lower) of these values.

My old sender used:

LoRa.setSpreadingFactor(12); // ranges from 6-12,default 7 see API docs
LoRa.setSignalBandwidth(62.5E3); // for -139dB (page - 112)

Its for use here on the farm so I’m after maximum achievable range. Occasionally I have the odd calf I’m nursing, and I like to have them out on fresh grass and in the sun but sometimes they wonder and being potentially weak can get stuck in thorn bushes. Just means I can find them a-little easier. Its working just I would like to reduce the bandwidth to increase the signal durability, sends once an hour when switched on.

Thank you for replying. Cheers, James

#4

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You’re right. Lora has its own range of bandwidth.

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#5

The chip onboard supports it - but its too advanced coding for me, I was hoping someone else had already done it, or a walk through tutorial. Slightly frustrating! my other units I made are sealed in cases permanently with resin so I can’t update the bandwidths. Just I didn’t relies the problem and I have another few AB02S arriving!

#6

We will try it later. If it can be used, we will release it.

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#7

Thank you - do you have an an idea when your team will be able to look into it? or would you be kind enough to post back on this thread if you succeed just I will probably miss any update.

Cheers,