Digital Audio Broadcasting
Digital Audio Broadcasting is a digital radio standard for broadcasting digital audio radio services in many countries around the world, defined, supported, marketed and promoted by the WorldDAB organization. The standard is dominant in Europe and is also used in Australia, and in parts of Africa and as of 2025, 55 countries are actively running DAB broadcasts as an alternative platform to analogue FM.
DAB was the result of a European research project and was first publicly released in 1995, with consumer-grade DAB receivers appearing around the late 1990's. Initially it was expected in many countries that existing FM services would switch over to DAB, although the take-up of DAB has been much slower than expected. In 2023, Norway became the first country to have implemented a national FM radio switch-off, with Switzerland to follow in 2026 and others territories in the process of planning a switch-off. Terrestrial digital radio has become a requirement for all new cars sold in the EU since 2021.
The original version of DAB used the MP2 audio codec; an upgraded version of the system was later developed and released named DAB+ which uses the HE-AAC v2 audio codec and is more robust and efficient. DAB is not forward compatible with DAB+. Today the majority of DAB broadcasts around the world are using the upgraded DAB+ standard, with only the UK still using a significant number of legacy DAB broadcasts.
DAB is generally more efficient in its use of spectrum than analog FM radio, and thus can offer more radio services for the same given bandwidth. The broadcaster can select any desired sound quality, from high-fidelity signals for music to low-fidelity signals for talk radio, in which case the sound quality can be noticeably inferior to analog FM. High-fidelity equates to a high bit rate and higher transmission cost. DAB is more robust with regard to noise and multipath fading for mobile listening, although DAB reception quality degrades rapidly when the signal strength falls below a critical threshold, whereas FM reception quality degrades slowly with the decreasing signal, providing more effective coverage over a larger area. DAB+ is a "green" platform and can bring up to 85 percent energy consumption savings compared to FM broadcasting.
Similar terrestrial digital radio standards are HD Radio, ISDB-Tb, DRM, and the related DMB. Also 5G Broadcast is developing globally for radio and television broadcasting. This system has the potential to enable digital terrestrial radio reception also in smartphones.
History and development
Eureka-147 project
The DAB standard was initiated as a European research project. It began in the 1980s with the collaboration of the West German Institut für Rundfunktechnik in and the French Centre commun d'études de télévision et télécommunications. The consortium formed in 1986 and numerous other European broadcasting organisations such as the BBC had also joined. It eventually became a project of Eureka and was named the Eureka-147 DAB Project in 1987, with the stated goal of developing a system that "would produce improved reception compared to FM...and with the potential to offer additional services such as text and other data, conditional access, enhanced traffic services, and picture transmission". Efficient bandwidth, low transmitting power, good reception in cars and audio quality comparable to CD, were some of the other goals.The first DAB demonstrations were held in 1988 in Geneva during WARC-88 conference, after which numerous other trials took place throughout several other countries in Europe. There was also a demonstration at the 1991 NAB Show in the USA. The MPEG-1 Audio Layer II codec was created as part of this project. DAB was the first standard based on orthogonal frequency-division multiplexing modulation technique, which since then has become one of the most popular transmission schemes for modern wideband digital communication systems.
A choice of audio codec, modulation and error-correction coding schemes and first trial broadcasts were made in 1990. A significant decision was the assigning of frequencies on the radio spectrum, as it was decided to operate the system on different bands compared to those used on FM and AM. The protocol specification was finalized in 1992 or 1993 and adopted by the ITU-R standardization body in 1994, the European community in 1995 and by ETSI in 1997. The European DAB Forum was formed in 1995, and the Eureka-147 project itself had "ended" and merged into WorldDAB in 1999.
Launch and early adoption
Pilot broadcasts were launched in 1995: the Norwegian Broadcasting Corporation launched the first DAB channel in the world on 1 June 1995, and the BBC and Swedish Radio launched their first broadcasts later in September in the UK and Sweden respectively while in Germany a pilot broadcast started in Bavaria in October 1995. Commercial stations in the UK started broadcasting in November 1999 as Digital One.The earliest DAB receivers in 1995 were semi-professional units for cars with separate boxes fitted in the boot. They were manufactured by Alpine, Bosch, Grundig, Kenwood, Philips and Sony, designed for evaluation purposes. These were complex systems based on either a DAB channel-decoder chipset from the JESSI project, or on general-purpose DSPs. Prototype consumer grade DAB receivers with improved silicons were first shown in 1997, but manufacturers were reluctant to release receivers in Europe partly due to the delay of DAB's launch in Germany. By 1999, most DAB receivers remained expensive car-based black box units and a handful of Hi-Fi home tuners.
It took some more time until further advancements in the integrated circuits helped to make DAB more accessible: notably Texas Instruments's DRE200 chip, released in 2001, significantly reduced the cost and size of the boards. This chip finally made portable DAB radios possible, and the first working prototype of a pocket DAB radio was presented by Roke Manor Research, part of Siemens, using a module named GoldCard II designed with Panasonic. Eventually the rise of affordable home DAB receivers, notably beginning with the Pure Evoke in 2002, helped to take off DAB to consumers for the first time.
However, adoption remained generally slow for various reasons such as high receiver costs and limited reception, with the exception of the United Kingdom and Denmark. In the UK, DAB radio receivers were high selling and 10% of households owned a DAB radio as of 2005, partly due to local manufacturers creating affordable receivers. In many other countries, such as Germany, Finland, and Sweden, DAB was unable to take off. By 2006, 500 million people worldwide were in the coverage area of DAB broadcasts. In 2006 there were approximately 1,000 DAB channels in operation worldwide.
Creation of DAB+
The World DMB Forum instructed its Technical Committee to work on an improved digital radio system. This work led to the creation of DAB+ in 2006. This new standard is based on DAB but uses newer MPEG-4 compression instead of MPEG-2, making it far more efficient and allowing more services to be broadcast without a loss in audio quality.The HE-AAC v2 audio codec was adopted for DAB+. AAC+ uses a modified discrete cosine transform algorithm. It has also adopted the MPEG Surround audio format and stronger error correction coding in the form of Reed–Solomon coding. DAB+ has been standardised as European Telecommunications Standards Institute TS 102 563.
As DAB is not forward compatible with DAB+, older DAB receivers cannot receive DAB+ broadcasts. However, DAB receivers that were capable of receiving the new DAB+ standard after a firmware upgrade were being sold as early as July 2007. Malta was the first country to launch DAB+ broadcasts in Europe in October 2008 and DAB+ broadcasts have since been trialled or launched in more countries. If DAB+ stations launch in established DAB countries, they can transmit alongside existing DAB stations that use the older MPEG-1 Audio Layer II audio format, and most existing DAB stations are expected to continue broadcasting until the vast majority of receivers support DAB+.
Growth in 2010s
In such countries where DAB was unsuccessful, efforts were made in later years to "re-launch" it using the newer DAB+ standard. it started gaining traction throughout the 2010s and finally took off in countries like France by 2019. DAB+ had launched broadcasts in various countries such as Australia, Czech Republic, Denmark, Germany, Hong Kong, Italy, Norway, Poland, Switzerland, Belgium, the United Kingdom and the Netherlands. Its UK launch occurred in January 2016 and the new national network Sound Digital launched with three DAB+ stations. A number of stations, such as Classic FM, have since switched from DAB to DAB+.DAB adoption in automobiles became increasingly common during this time, and by 2016 it was standard in most cars sold in the UK, Norway and Switzerland. Since 2021, terrestrial digital radio has been compulsory on cars sold in the European Union as well as Saudi Arabia.
As of 2018, over 68 million devices have been sold worldwide, and over 2,270 DAB services are on air. Malta, Monaco and Kuwait achieved 100% coverage of DAB in 2018.
DMB and DAB-IP
and DAB-IP are related standards that were developed for mobile radio and TV, they support MPEG 4 AVC and WMV9 respectively as video codecs. However, a DMB video subchannel can easily be added to any DAB transmission, as it was designed to be carried on a DAB subchannel. DMB broadcasts in South Korea carry conventional MPEG 1 Layer II DAB audio services alongside their DMB video services., DMB is currently broadcast in Norway, South Korea, and Thailand. Trials for DAB-IP were held in London in 2006, as "BT Movio". It competed with DVB-H and MediaFLO which were also under testing.Countries using DAB
Fifty-five countries provide regular or trial DAB broadcasts. In spectrum management, the bands that are allocated for public DAB services, are abbreviated with T-DAB.In the European Union, the European Electronic Communications Code entered into force on 20 December 2018, with transposition into national legislation by Member States required by 21 December 2020. The Directive applies to all EU member states regardless of the status of DAB+ in each country.
This means that since the end of 2020, across all EU countries, all radios in new cars must be capable of receiving and reproducing digital terrestrial radio." Following this directive, Belgium stopped all sales of analogue radio receivers from 1 January 2023. Thus, consumers are no longer able to purchase AM or FM receivers for domestic use. "The obligation to incorporate DAB+ for new cars and domestic radio receivers is a nice step ahead in the digitisation of our radio landscape," commented Benjamin Dalle, the Flemish media minister.