Kukuruku: A new SDR client that supports RTL-SDR

A new general purpose SDR software package called “Kukuruku” has recently been released. It appears to be a Linux only based client which is based on GNURadio. The authors write that they have several interesting features which we quote below:

Network transparency. Process the data remotely and send to the client only waterfall pixels and filtered narrowband channels instead of the entire SDR baseband. With this, you can use the SDR remotely over WAN.

Multiple demodulators running at once. How the hell can this be missing?

History browsing. It happens to me all the time: I see a new station scrolling on the waterfall. Before I manage to tune to it, it disappears (or at least the callsign is over). I have 8 GB of RAM, so why can’t I store the last minute of the entire SDR baseband for future reference?

Pluggable demodulators. Why is it so much pain to add GSM, Tetra, Tetrapol and other modes to existing software? I just want to provide a binary and have the data piped to stdin.

Squelch sucks. The squelch should not care about absolute signal level, but about level relative to surrounding channels. Additionally, it should have hysteresis and a small buffer, so when it triggers, it correctly replays the beginning of the conversation. Oh, and when recording, the squelch should timestamp the parts of conversation.

Histogram. It is difficult to see clipping on the FFT output. Why don’t we have histogram of samples?

Autotune/AFC. Obvious.

Scanner. Both for automatic demodulating all peaks in the spectrum and for retuning the SDR and finding stations. Even the crappiest rtl-sdr has 2 MHz bandwidth and can retune in 50 ms. This means 1600 channels per second. Compare this with commercial scanners.

At the moment one interesting plugin for Kukuruku is the TETRA plugin. The plugin appears to use tetra-listener and TERAPOL-kit as the demodulators, and simply passes the signal data to them for decoding and audio output.

The installation instructions can be found on the user guide. So far we unfortunately haven’t been able to install and test the software due to several compilation errors occurring, so if anyone tries this out and gets it to work, please post any installation tips in the comments. 

Kukuruku running and demodulating TETRA audio with a plugin.
Kukuruku running and demodulating TETRA audio with a plugin.


  1. landry


    I clone kukuruku in my home directory how I should do to make it work I have to look good help file my question is how can I find my server by default because it is a 4444 or should I add ? how and created a $ PATH with tetrapol_dump and tetra-rx?

    in waiting for your response


    • rengar paw

      Server&Client run fine in my VM, but i tried to demod a FM Broadcast, and im not getting any audio.
      “/home/jenda/tmp/kukuruku/client/modes/wfm.py: not found”
      “works on my machine”, right?

      • Jenda

        admin: This is really weird, at first it fails to read from osmosdr and then it segfaults. Would it be possible to open the coredumo in gdb and see where it fails?

        rengar paw: You need to edit path to modes directory in ~/.kukuruku/modes. Maybe “./” or the base dir of the kukuruku-gui.py script should be there by default, but then it won’t work if you put the it for example to /usr/local/bin either. How can this be solved?

      • Jenda

        Sorry, ~/.kukuruku/gui. The problem with this is that it should be in the documentation, but someone discovered this project and posted it here about one week before I planned to release it, so the documentation was not yet ready 😉

Post a comment

You may use the following HTML:
<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>