“Using GNURadio for Analog and Digital Communication” – 31th of January, hsbxl (hackerspace Brussels)

On Thursday, the 31th of January, hsbxl (hackerspace Brussels) will be hosting a workshop “Using GNURadio for Analog and Digital Communication”. This workshop is part of the “radio-day” of the byteweek event, a week-long event of presentations, programming-sessions and workshops held the week before the FOSDEM conference in ULB. (1)
The workshop aims to introduce the participants the possibilities and use of GNUradio, an open-source framework for SDR (Software Defined Radio), using examples from amateur-radio.

  • SDR: software defined radio

SDR has become a standard part of the amateur radio toolkit: digimode-software like hamradio-deluxe or fldigi, software for weak-signal modes like WSPR and FT-8, SDR transceiver-kits like the limaSDR, the RTL-dongle or funcube to decode signals from amateur-radio satellites or APRS signals. We use remote listening stations like the websdr, radios like the flexradio that have a build-in waterfall display and almost every modern handheld radio is based on a transceiver chip based on SDR technology.

But what is SDR? How does it work? How can you implement a complete tranceiver in a computer or a radiochip? And how can a SDR radio implement features in software that are not possible to do using analog components? And how can you use SDR to implement new features that do not exist yet?

To answer these question, GNUradio comes in.

  • GNU Radio

GNUradio is SDR software of a different kind.
While the examples above use SDR technology, these are all end-user applications: pieces of software that implement a certain specific function.
GNU Radio -on the other hand- is not an end-user application. It is a framework to create a Software-Defined Radio inside a computer, a tool to design SDR-systems.

GNU-radio consists out of three parts:

  • processing-blocks:
    These pieces of software implement one particular SDR function: a FM demodulator, a low-pass filter, a mixer, a RTL-dongle input block, a waterfall visualisation block, etc.
  • the “gnuradio companion”:
    This is a tool that allows users to visually combine processing-blocks and create a so-called “flow-graph”: a description of how signals flow from one block to another. One example may be: RTL-dongle receiver -> tuner -> FM demodulator -> low-pass filter -> amplifier -> PC speaker output
  • The 3th part, the gnuradio back-end is mostly invisible for the users:
    This is the engine that does the actual process of transporting signal-data from one block to another.
  • Workshop:

For amateur-radio, GNUradio has three main uses:

  • as an educational tool to learn more about SDR, .. or just about just radio-technology itself
  • as a tool to use as a receiver or a transmitter
  • as a tool to develop new radio-technology that do not yet exist

The “Using GNURadio for Analog and Digital Communication” workshop is given Derek (MW0LNA) and Marcus Mueller (Karlsruher Institut für Technologie). Derek and Marcus are two of the main developers of the GNUradio project.

The main focus of the workshop is to teach people what is GNUradio, what is can do, and how it can be used to model amateur-radio systems.

This event is -as its name indicates- a workshop, a session where you are expected to participate actively yourself. As such, you are expected to bring your own laptop with you to the event. Also, as the goal is to keep the workshop focused on using and learning GNUradio itself (and not just installing it), a USB bootable-disk is used that provides you with a ready-to-use system with all software ready to use. (2)

RTL dongle -used as receiver- are provided by the organisers.

The workshop starts at 8 PM, and will take up to 2 and a half hours (so up to 10h30 PM).

As already mentioned, it doesn’t happen that many times that this kind of workshop is organised in Belgium. So, if you are interested in really understanding SDR and how to use it for amateur-radio, this is a special opportunity.

To keep the workshop manageable, it is limited to 20 places.
Please use this link to register.

73 – kristoff – ON1ARF

If there are any questions, feel free to contact me, either via mail

(on1arf {@} uba.be), or via DMR (2060073).

ON1ARF do a presentation “amateur radio for hackers” at 6PM the same day

(1) “byteweek” event: https://hsbxl.be/events/byteweek/2019/

(2) You are asked to -either- bring a 8 GB flash-drive to the work

(2) You are asked to -either- bring a 8 GB flash-drive to the workshop.
If possible, please flash the following ISO image on the drive beforehand:


As another option, a USB flash-drive will be provided at cost. (of course, you can then keep the USB flash-drive afterwards), but do let us know beforehand so we know how many flash-drives we need to forsee.

“electronics-Belgium” talkgroup on DMR: 20603
“electronics-Worldwide” talkgroup on DMR: 98008