Installing GNURadio

    This is how to install GNURadio and all required components to make GNURadio work with the FreeSRP.

    Note: This has been tested on Ubuntu 14.04.

    Downloading the latest firmware

    The FreeSRP's FPGA needs to be programmed every time it is plugged in. This happens automatically, but you will need to download the latest FPGA bitstream and USB controller firmware from here.

    Make a new directory in your home directory named .freesrp. Place the downloaded fpga.bin and fx3.img in there.

    Testing your installation

    Plug the FreeSRP into a USB 3.0 port. Open a terminal and run:

    freesrp-ctl --fpga="$HOME/.freesrp/fpga.bin"

    If everything is installed correctly, after a few seconds you will see:

    Found FreeSRP
    Loading FPGA with '/home/user/.freesrp/fpga.bin'
    FPGA configured successfully
    Connected to FreeSRP
    Version: FX3 v0.1.0, FPGA v0.1.0

    You are now ready to use your FreeSRP! To use it with GNURadio, continue reading.

    Using GNURadio to access the FreeSRP

    GNURadio lets you build signal processing pipelines (even graphically, using GNU Radio Companion!), and after the installation procedure you just completed, GNURadio can use the FreeSRP as both a signal source and a sink.

    Download the receiver example and open it in GNU Radio Companion. Start the flowchart and you should see an FFT of the signals being received, and you can tune center frequency, sample rate, filter bandwidth and gain.


    To use the FreeSRP in Gqrx, configure the I/O device with:

    • Device: Other...
    • Device string: freesrp fpga
    • Input rate: 40000000 (or whatever you like, up to 56 million)
    • Bandwidth: 40 MHz (anything up to 56 MHz)

    You can leave everything else at the defaults. Gqrx should now be able to receive data from the FreeSRP.