Hello everyone,
I’m quite new to SDR, so this may be an obvious question. I don’t have a spectrum analyzer, but I’d like to analyse the signal generated when transmitting from the lime. I recently watched this video using satsagen with the Pluto: Spectrum Analyzer and Tracking Generator with Pluto SDR - YouTube
My understanding is that satsagen does not support the lime, but I was wondering if I could do something similar using qspectrumanalyzer or lime suite tools shown here LimeSDR - All-in-One Lab and GNU Octave | Crowd Supply.
If I understand correctly, it would not have the tracking generator that satsagen has, but could I just tell the lime to transmit a certain signal, connect the tx to rx (with proper attenuation) and read the resulting spectrum?
This may be far from finished, but if you are interested in a way to make a Spectrum Analyzer work based on the limesuite C API, feel free to check out my repo: https://github.com/fabske98/Lime-SDR-Spectrum-Analyzer.
Its still a work in progress and the GUI is yet to be implemented, and more features to be added. But it should be good for playing around a bit and plotting some frequency spans already.
You should be able to create a flow graph with your Lime as
a source (ie transmitter), reading a file containing your signal, or using the available blocks to create the signal
a sink (ie receiver), displaying the spectrogram/waterfall
The LimeSDR-USB can have different sampling rates for RX and TX but are not completely unrelated (basically you can have TX = RX / 2^n, see Link between RX and TX sampling rates for more, but I recall also having issues in some cases). It can have completely different frequencies though.
I think with the LimeMini the RX and TX sampling rates must be the same.
Hi Grant
It is certainly possible to use the LimeSDR as an effective spectrum analyzer. Take a look at this simple solution using a Raspberry Pi 3 and a 7 inch touchscreen: Portsdown Band Viewer
