![]() ![]() The term "DAB" most commonly refers both to a specific DAB standard using the MP2 audio codec, but can sometimes refer to a whole family of DAB-related standards, such as DAB+, DMB, and DAB-IP. In October 2018, the WorldDAB organisation introduced an all-new logo for DAB (specifically DAB+) to replace the previous logo that had been in use since before DAB's initial launch in 1995. ![]() As of 2018, over 68 million devices have been sold worldwide, and over 2,270 DAB services are on air. In 2006 there were approximately 1,000 DAB stations in operation worldwide. This work led to the launch of the DAB+ system.īy 2006, 500 million people worldwide were in the coverage area of DAB broadcasts, although by this time sales of receivers had only taken off in the United Kingdom (UK) and Denmark. The AAC+ audio coding standard uses a modified discrete cosine transform (MDCT) audio data compression algorithm. In October 2005, the World DMB Forum instructed its Technical Committee to carry out the work needed to adopt the AAC+ audio codec and stronger error correction coding. Pilot broadcasts were launched in several countries in 1995. The protocol specification was finalized in 1993 and adopted by the ITU-R standardization body in 1994, the European community in 1995 and by ETSI in 1997. Public demonstrations were made in 1993 in the United Kingdom. DAB was the first standard based on orthogonal frequency-division multiplexing (OFDM) modulation technique, which since then has become one of the most popular transmission schemes for modern wideband digital communication systems.Ī choice of audio codec, modulation and error-correction coding schemes and first trial broadcasts were made in 1990. The MPEG-1 Audio Layer II ("MP2") codec was created as part of the EU147 project. Later, DAB was developed as a research project for the European Union ( EUREKA), which started in 1987 on an initiative by a consortium formed in 1986. The first DAB demonstrations were held in 1985 at the WARC-ORB in Geneva, and in 1988 the first DAB transmissions were made in Germany. 6.1.4 Less unlicensed ("pirate") station interferenceĭAB has been under development since 1981 at the Institut für Rundfunktechnik (IRT).4.2 Use of frequency spectrum and transmitter sites.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 so far, Norway is the only country to have implemented an analog switchoff program. The majority of these services are using the upgraded DAB+ standard, with only the UK, New Zealand, Romania, Brunei Darussalam, and the Philippines still using a significant number of original DAB services. Īs of 2021, 42 countries are running DAB services. 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 (as is normal for digital broadcasts), whereas FM reception quality degrades slowly with the decreasing signal, providing effective coverage over a larger area. High-fidelity equates to a high bit rate and higher transmission cost. 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. ĭAB is generally more efficient in its use of spectrum than analogue FM radio, and thus can offer more radio services for the same given bandwidth. 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 (AAC+) audio codec and is more robust and efficient. Consumer-grade DAB receivers have been available in many countries since the millenium. The Norwegian Broadcasting Corporation (NRK) launched the first DAB channel in the world on 1 June 1995 ( NRK Klassisk), and the BBC and Swedish Radio (SR) launched their first broadcasts later that year. The DAB standard was initiated as a European research project called Eureka-147 in the 1980s. The standard is dominant in Europe and is also used in parts of Africa, Asia, and Australia other worldwide terrestrial digital radio standards include HD Radio, ISDB-Tb, DRM, and the related DMB. Digital Audio Broadcasting ( DAB) is a digital radio standard for broadcasting digital audio radio services in many countries around the world, defined and promoted by the WorldDAB forum.
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