How many bits will be transferred every two seconds?

1

Hi guys
I would like to send data from 1-10 end devices to gateway every two second.
My ideal payload is 130 byte,
I have just understood LoRaWAN is not a good choice for this data range. My recent question is: how many bits will be transferred every two seconds?

2

Indeed, this is not allowed

Approximately one per node.

Yes, one bit.

Actually packets would be longer (especially as they cost at least 13 bytes of framing overhead), but they’d also have to be much less frequent than every 2 seconds.

So if you tally the airtime you’re allowed to send over the course of a day, and divide it by the length of a day, then a bit every two seconds is on the order of magnitude of what is allowed.

And that’s under ideal conditions using the fastest ordinary data rate with SF7BW125

(If you use 130 byte packets, then your fixed framing overhead is a smaller fraction of bandwidth and you might get up to 3 bits per 2 seconds per node, but remember that none of this is reliable, so an error may wipe out even more data with a long packet)

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3

thank you indeed for your speedy response.
i got it :ok_hand:

4

130bytes every 2 seconds, really ?

At the fastest, i.e. closest to a Gateway settings, that would represent 11 times the legal limit of a 1% duty cycle.

At long range and at 100% duty cycle it would take 4.5 seconds to send that amount of data.

Not legal or practical for LoRaWAN, you would exceed the fair use limit after sending data for just 30 seconds.

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