Adafruit LoRa -> RTCM3 -> Reach LoRa --- how?


I previously asked if it is possible to make Reach m+ with LoRa to gain RTCM3 messages from internet server and pass them on to other Reach M+´s on site. Finally the answer was no - the Reach will gain correction over internet but it will send correction data based on it´s owm location. Which gave terrible results in practice.

We still need to achieve this: spread rtcm messages coming from internet to bunch of Reach M+´s via LoRa. Is it possible to make, say, Adafruit microcontroller to fetch the correction data and pass it on with Adafruit LoRa radio on same frequency? Are there any other specs or protocols that would need to consider?

So more clearly. Setup would be:

[PC with public IP providing RTCM3] -> internet / IP -> [Local server on microcontroller reading RTCM3] -> Serial -> [Adafruit LoRa sending RTCM3 on 868MHz] -> 4x [Reach M+ receiving correction data]

EDIT: OR is it possible to attach Emlid LoRa-radio directly to PC with,say, TTL-cable?

Hi @pekka.pylkkonen,

Reach M+ LoRa module hardly can be compatible with another LoRa module. There is a slight difference between different LoRa modules, it’s a feature of the protocol.

It’s also not possible to connect Reach M+ LoRa module to PC. Reach M+ LoRa can be connected only to Reach M+ unit.

Could you please tell more about the result you got with this setup? May I ask you to share logs from your Reach units?

So sad…

Reach´s are in such a place that I am unable to get to them for some time. The one that was supposed to deliver correction data from internet is in crane, and so it moves very rapidly due to machine movements. Other ones showed that they received correction data from it and claimed to be in float mode, but their locations wandered around rapidly tens of meters. Much worse than without correction data.

Do You have any ideas for this?

1 Like

Hi @pekka.pylkkonen,

Do I understand right that the base unit is moving?
The base should be stationary, otherwise, you can’t gain the required accuracy.

Interesting. You say “There is a slight difference between LoRa modules, it’s a feature of the protocol?” Are you sure? I’ve been studying LoRa and the GlobalSat LM-210H module in the Reach RS+, and there’s something odd in the LM-210H I’ve never seen elsewhere. Along with the “up-chirps” and “down-chirps” there are “ricochet-chirps” I’ve never seen before in other LoRa devices.

The LM-210H seems like a great part, since an on-board microcontroller handles a lot of the tedious parameters. But in spite of this simple interface, the LM-210H disappeared from the GlobalSat web site and I can’t find it available for sale anywhere. This makes me worried it’s a flawed product, and it’s incompatibility with any other LoRa devices may not be “a feature of the protocol” but something wrong/different with the LM-210H.

Please tell me I’m wrong. I want to be wrong. Since LoRa modules are all based on the Semtech transceiver chips, they should be compatible, unless there’s an error somehow.

  • tj.
1 Like

Hi @tejones777,

GlobalSat has replaced LM-210H module with the next one.
That is why the LM-210H chip is not available for sale online.

What is the other product which can connected to LM210H?

Hi @dicky,

We haven’t tested other LoRa modules with our devices, so I hardly can recommend you something.

This topic was automatically closed 100 days after the last reply. New replies are no longer allowed.