Opendigitalradio is the result of a group of people with a passion in radio, transmission technology and open source sofware. Here’s a timeline of the project that helped to democratise DAB transmission from early tools designed for lab testing to regular licensed DAB+ transmission using free open source software and Software Defined Radio.


  • Creation of mmbTools project by François Lefebvre and Pascal Charest from CRC in Canada. It consists of a DAB multiplexer, OFDM modulator and player using gnuradio for the Ettus USRP1 Open Sofware Defined Radio platform, all running on Linux. (See Presentation from François done at the EBU Radio Summit 2011 on the tools developped by CRC)


  • Discovery of the CRC-mmbTools at IBC exhibition in Amsterdam by Mathias Coinchon and Stan Roehrich. CRC-mmbTools is the original project started by François Lefebvre (project manager) and Pascal Charest (lead developer) at the Communication Research Center in Canada (CRC). It consists of a multiplexer (CRC-DabMux) and modulator (CRC-DabMod) running on a Linux PC and using the Ettus USRP1 for the creation of the signal. At that time, the software was not open source.
  • CRC starts a website dedicated to the CRC-mmbTools (it can still be found on archive.org) with the possibility to create a DAB ETI file (transport stream) online. A live CD is also created where it is possible to boot the tools on a PC without having to install them.
  • First test by Mathias Coinchon to transmit a live DAB signal using the CRC-mmbTools, combined with the toolame open source encoder on a linux PC and the Ettus USRP1, the first affordable Software Defined Radio Peripheral (~1000$). Video


  • September: CRC opens the source code of the multiplexer (CRC-DabMux) under the terms of the GPL licence.
  • October: Creation of the opendigitalradio.org wiki for documenting the experiments around the CRC-mmbTools and to serve as a knowledge base for other open projects in broadcasting (for Digital Radio Mondiale, FM, etc.).
  • Workshop at 26C3 on digital broadcasting using the CRC-mmbTools


  • February (at the WorldDMB TC during EBU digital radio week): François Lefebvre announces that CRC opens the source code of the modulator (CRC-DabMod) under the GPL licence. See Presentation
  • Launch of the CRC-DABPLUS DAB+ encoder by CRC.
  • Total Broadcast uses CRC-DabMux multiplexer on commercial DAB transmitters (fed by ETI) for a transmission in Ireland
  • September: First licensed DAB transmission using CRC-mmbTools for a temporary transmission of 8 DAB channels for a performance at a music festival in Lausanne. The installation consists of a PC and USRP1 in a garden box lying on a ticket vending machine. See video
  • Presentation and demo of the concept of low cost solution for small-scale DAB at WorldDMB General Assembly in Belfast


  • Long-term test DAB+ transmission in Denmark in the region of Copenhagen by Ulrik Brink from Kanal Plus using CRC-mmbTools. It consists of a group of community radio stations.
  • Presentation and demo of the open source and SDR approach for DAB+ transmission to the association of non-commercial radio in Switzerland (UNIKOM). This triggers a big interest, Lukas Weiss, president of Unikom and Thomas Gilgen, who owns the openbroadcast radio station and looks for ways to go back on DAB+, decide to undertake the process of requesting a regular DAB+ license for operating a local and community radio station multiplex.
  • Presentation and demonstration of DAB-in-a-box concept at UK TechCon conference in Manchester (see James Cridland report).


  • February: Demonstration of a live high-power DAB+ transmission over Geneva at the EBU radio week. The objective is to demonstrate that DAB+ is also a possibilty for small and community stations by using lower cost infrastructure.
  • July: Matthias Brändli completes his diploma master thesis at EPFL in collaboration with CRC and EBU on the implementation of DAB SFN feature for the CRC modulator. EBU News item.
  • 1st November: Creation of Opendigitalradio as a non-profit association under the Swiss law with the current missions. The decision is also motivated by the need of an organisation to maintain a transmission site in Lausanne for temporary FM stations.
  • CRC has experienced a restructuration where the research on broadcasting has been reduced and the management decides to drop the support for the  CRC-mmbTools probably also because DAB has never taken off in Canada.


  • June: Digris is granted a license for operating “DAB islands” in Switzerland. Opendigitalradio will provide the transmission solution based on open source. The pilot transmission will be in Geneva and Zurich. Digris starts the tender to the radio stations.
  • OFCOM UK publishes a report on small scale DAB after a DAB trial using the CRC-mmbTools done in Brighton by Rashid Mustapha.
  • Serguy adds the DAB+ support to fdk-aac encoder (960 transform, superframing, firecode, RS). There’s now an open source DAB+ encoder ! He also builds the simplest DAB transmission prototype with a custom SDR development.


  • February: Opendigitalradio decides to fork the CRC-mmbTools project to ODR-mmbTools. François is informed about the decision. It is based on the fact that many changes have been made to the original tools by Matthias Brändli and the situation led to some confusion about the state and versions of the CRC-mmbTools. There was the need to put in place a software repository with version management. Opendigitalradio becomes the maintainer of ODR-mmbTools and Matthias Brändli the lead developer. The ODR-mmbTools are moved to repositories on github.
  • CSP from Italy contributes to the encoder by opening the code of their MOT encoder. They also open the ETI analyser tool etisnoop.
  • http://mmbtools.crc.ca goes offline after management decision. It can still be accessed through archive.org.
  • 1st May: Regular licensed DAB+ transmission starts in Geneva with 5kW ERP and 14 radio programmes. Digris is the operator company.  Stan Roehrich has done the planning, site building and maintenance. The ODR-mmbTools software is used.
  • June: ADN, a small community radio station operator in Marseille is starting DAB+ multiplex (SDN) in Marseille area using the ODR-mmbTools.
  • 1st September: Start of the regular transmission in Zurich.


  • Single-Frequency Network functionality is nearing completion, first trials are already planned.
  • The tools receive new contributions from the community (PAD refinements).

The association will pursue its efforts to develop and maintain this public free open source set of software and make sure that the GPL licence is respected hoping it will become a reference for local broadcasting and industry.