myriadrf / lora-sdr Goto Github PK

This call is in the latest release and should cleanup the popBuffer() stuff.

Thank you to provide a project to help me comprehend LoRa decode process, I tried and it really works, but i still have a question about the whitening polynomial, can you give me a hand? thank you so much.

I dont see anywhere in the demodulation chain where the preamble detection is done. I would think it would be in the LoRa Demod block but there is no such parameter. I'm using an SX1276 chip and trying to read a packet with a RTL2832U. I am recieving the signal no problem via pothos but the signal wont make it past the LoRa Demod block.

I try to open the example .pth files and it will not read them. Forcing it / changing extension to .pothos, will give this error: PothosFlow.GraphEditor: Error parsing JSON: illegal value

When installing LimeSDR-LoRa, there are two Prerequisites not mentioned by the author.

The first Prerequisite is to install Poco C++ library.
sudo apt-get install libpoco-doc libpoco-dev

And another is to install 'nlohmann-json-dev' package as shown in #12.
sudo apt-get install -y nlohmann-json-dev

Hello everyone and happy new year !!!

I am trying to activate the topology in Pothos Flow for example lora_sdr_client.pth and lora_sdr_relay.pth and neither of them works.
No exception is printed on the console.

I am running LimeSDR and using Windows 8.1.

I think the issue is caused because I have not built the project. But lora_simulation.pth works (although buggy see issue) which means that it can find the LoRaEncoder LoRaDecoder modules.

How should I go about to troubleshoot this problem?

Would it be possible to use this project to implement a LoRa skimmer (similar to https://en.wikipedia.org/wiki/CW_Skimmer)? i.e. receive all LoRa packets transmitted with any frequency (within the SDR's frequency range/bandwidth, of course), bandwidth, spreading factor, coding rate, sync word, etc.

Related to #14

I try to decode LoRa header, this is encoded in the 8 symbols which follow the reverse-chirp 2+1/4 symbol part. Can someone confirm that the code in this repository has proper algorithms for this part ?
I have the symbols, but I can't make sense of them after deinteleave.
Do I need to de-whiten then as well ?
Is there anybody knowledgeable here, who could clarify the details ?

I was able to receive these signals on sx1276 in implicit header mode, but not explicit mode.
It appears to send a longer packet when I put a message into the chat box, which would imply explicit mode. (implicit mode is fixed-length)

this link is obsolete

i am sorry to bother you that i can't find file Framework.hpp.please tell me where i can find this,thank you very much.

In the case where the symbol set is equal to (and not greater) than spread factor, we are guaranteed +/-1 decoding errors. When the symbol set is greater, the detector error is simply shifted out. To correctly decode this, we need to take into account all of the symbol possibilities that go into one set of interleaved symbols and use the hamming errors to select the best decode option.

Two major complications to implement this:

• Because of interleaving, errors are spread across every N symbols. The maximum likely hood path is as long as 1 group of interleaved symbols. But not as long as the entire payload, the process just repeats for every group
• The header options support their own code rate separate from the payload (usually 4/8). So doing this requires its once in a generic way for the payload, and somewhat specifically for the header decode.

Dear all,

Is it possible to run the code with 2 LimeSDR boards https://wiki.myriadrf.org/LimeSDR-USB? I am thinking about configuring one LimeSDR device as a gateway, and another one as a device. Optionally, I can use USRP B210/USRP X310. Will I be able to easily accomplish that with your code?

Thanks in advance,

Best regards,
Eryk Schiller

I try to run lora_simulation but it receive 10 lora packet (0 to 9) and after that all packet are dropped.

Did I miss something ? (by the way thanks for those examples)

Hey guys, this is more a request than an issue.

The LoRa Demodulator currently ignore packets that don't match the sync word.
Could you help me how to remove that sync word check so I can receive any LoRa packet. For a study project I have an arduino set up that sends packets and I'd like to receive them in Pothos.
Any help would be greatly appreciated as I'm new to all of this.
Kind regards

Having installed Pothos via the PPA on Ubuntu and then trying to install this project from source via Git, you should mention that the package "nlohmann-json-dev" (via Ubuntu) is a requirement or that https://github.com/nlohmann/json.git will be needed.

Why doesn't it work on bladerf?