The radio technology known as Digital Audio Broadcasting (DAB), and its TV sibling, Digital Multimedia Broadcasting, is being operated in several regions worldwide, either in the form of full commercial services, or as feasibility studies. Along with the UK, there is also a growing user base in countries as Denmark, Norway, Germany, Belgium, Switzerland and South Korea.
This article provides brief information on most of the regions using DAB, DAB+ and DMB.
There were two public radio stations (Ràdio Nacional d'Andorra and Andorra Música) broadcasting by this system. Their coverage was practically of 100% of the population of the principality, only using two repeaters: Pic de Maià and Pic de Carroi. The broadcast was carried out on the block 12D (229.072 MHz).
In 2005 the repeaters were deactivated and in 2006 definitely turned off up to the present without further explanations.
The major cities of Sydney, Melbourne, Brisbane, Perth and Adelaide all officially launched digital radio broadcasts on 6 August 2009, and the digital radio services include stations by public broadcasters ABC and SBS, as well as a number of local commercial stations. All of these broadcasts are in DAB+. Digital radio in rural areas is currently unavailable and there are currently no plans to introduce a digital radio service in these areas.
In Austria so far there is just a test operation of DAB. The national broadcasting company Österreichischer Rundfunk (ORF) tests Digital Audio Broadcasting in the capital Vienna and in the province Tyrol.
DAB was launched in Belgium in 1997. The transmitter network is rather dense, resulting in an excellent mobile coverage providing 10 public national radio stations.
The ensembles include audio services (four new "DAB only" programmes and simulcasts from FM),[1] programme related data (program type, announcements and dynamic label) and data services. The receiver situation is improving. Tuners, kitchen radios and handheld devices are on the market and sales are growing fast as a result of a marketing campaign. Investments in new DAB services and more networks are expected, especially for the commercial and regional networks. An upgrade of the transmitter network for excellent indoor coverage is planned.
As with most things in Belgium, Broadcasting is divided to serve the two language communities and DAB is catered for by the two Public broadcasters VRT and RTBF, - the later having recently upgraded their multiplex (with a system from the English DAB systems service provider) to enable it to (amongst other things) deliver the range of Advanced / enhanced digital services that the Eureka 147 protocol encompases.
L Band DAB was launched in Canada in November 1999 and dismantled in mid 2010.
Initially, the plan was to replace all AM and FM transmitters by Eureka 147 transmitters in the L Band. However, at no time did any radio station make a complete switch from AM or FM to DAB. Rather, many stations simulcasted in both analog and DAB as broadcasters waited for market acceptance before committing.
Early promotion of DAB was mostly done by the Canadian Association of Broadcasters though an organization called Digital Radio Rollout, Inc.[2] For most of the 1999 to 2010 period, CBC operated DAB stations in Toronto (VX9CUZ, Channel 6/LF) and Vancouver (VX9IXS Mount Seymour & VX9IXT Burnaby, Channel 3/LC). There were also later CBC DAB stations in Ottawa, Windsor, and Halifax, as well as commercial DAB stations in those markets.
The very slow public acceptance of DAB led to pressure from broadcasters to bring other digital radio formats to Canada. On 16 June 2005 the Canadian Radio-television and Telecommunications Commission (CRTC) approved two subscription satellite digital services, which are partnered with the Sirius (Sirius Canada Inc.) and XM services (Canadian Satellite Radio Inc.) in the United States, and a third subscription service that was to be provided by the CHUM radio group using terrestrial transmitters that would only cover mainly urban areas in the south, using a derivative of DAB. Among the services planned to be offered on the channels were urban music, rock, oldies, dance, Motown, Francophone, classical, opera, Christian, Aboriginal, and radio theatre. With CTVglobemedia's purchase of CHUM, however, there is currently no indication whether this would be rolled out.
On 15 December 2006, the CRTC, on reviewing the status of DAB in Canada and finding that it was not progressing well, changed its previous policies and allowed testing of digital systems being tried in the United States, including in-band and out-of-band FM systems. The Eureka 147 system was still allowed, but transitional licences would become permanent licences at renewal. Eureka 147 was now viewed as complementary, and broadcasters were allowed to add one Eureka 147 station for each AM or FM station they operated.
On June 24, 2010 the CBC announced they were shutting down all of their remaining DAB radio stations with the few remaining DAB stations in Canada not owned by the CBC expected to follow suit. This announcement marked the end of DAB radio broadcasting in Canada.
In 2006 China decided to use DAB and T-DMB has an industrial standard for broadcasting digital radio and mobile television. China placed early in 2006 an order of 500 000 receivers. There are DAB broadcast in Beijing, Guangdong, Henan, Dalian, Yunnan, Liaoning, Hunan, Zhejiang, Anhui and Shenzhen.[3]
Beijing has 4 mobile TV channels, 17 audio services, 5 video services and 3 data services including a service for downloading files and on‐demand media over the DAB network.
First DAB transmission in Croatia started from Sljeme (mount near Croatian capital Zagreb) in 1998. Although there hasn't been any additional enhancement of initial DAB service, this transmitter is still broadcasting DAB and it is the only one DAB transmitter in Croatia. The whole implementation od DAB system was invested by Croatian national broadcasting company (HRT) therefore this transmitter broadcasts only its three national radio programs (with bitrate 192kbps each). Some other commercial broadcasters announced preparations for DAB broadcasting but nothing has been realized yet. Today DAB transmitter is maintained by company OiV.
In April 2006 the Czech parliament adopted a version of the media law focused on digital broadcasting. The public Czech radio (Český rozhlas) has applied for permission to broadcast DAB. The new digital radio stations ČRo 4 - Radio WAVE, Rádio Česko, Leonardo and D-dur are provided by Czech radio. These programs are currently transmitting via DVB-T and the Internet.
The TELEKO Company, in cooperation with the public broadcaster Český rozhlas, began a DAB (three programmes) and DAB+ (two programmes) trial in the Pribram region on August 2007. The service covers almost 130,000 people. Regular services are expected in L-Band in autumn 2009.
In Denmark an extensive rollout of DAB has been made by DR. More info can be obtained from http://www.dabradio.dk/ including a current coverage map. About 18 channels are available, which includes 15 DR channels and one channel from SBS Radio NOVAfm. Denmark, along with UK are the most successful countries when it comes to DAB adoption. In 2010, 33% of the Danes has access to a DAB radio which makes Denmark the country with the most DAB users in the world per capita.
DAB coverage is about 90%. In the coming years, more channels are going to be available.
DR wishes to abandon the FM platform by 2015, and also later start DAB+ transmissions.[4]
The Finnish broadcasting corporation YLE started DAB transmissions in 1997, which covered approximately 2 million listeners. However, not many compliant devices were sold and hence the DAB transmitters were switched off in 2005, although transmissions of the digital radio channels continue in the digital television network.[5]
Finland is providing digital radio via other digital broadcasting systems, such as DVB-H.
France originally opted for a DAB-standard slightly different that the UK system, but in a public consultation on digital radio held in 2005, the four largest French radio broadcasters objected to using the current DAB system; new stakeholders were in favour of keeping compatibility with the UK version. The French communications regulator Conseil supérieur de l'audiovisuel (CSA) decided to launch a technical forum about the right choice for digital radio. Some broadcasters asked the regulator to strictly adopt the digital radio system in order to preserve transborder roaming (car radio) and some suggested to design technical variants of the European standard. Implementation of Band III has been strongly suggested by most contributors. The five largest French radio broadcasters together participated in a trial of the DVB-H and T-DMB digital broadcasting system in Paris. During the summer of 2009, the decision finally fell on the DMB-standard (T-DMB), and France has stated that all radios in sale must be DMB compatible by 1 September 2013 latest.
After some years of test operation, regular T-DAB service was launched in April 1999. Licences have been granted to 8 different network operators. They use the T-DAB frequency blocks of the WI95 Plan. The cumulative area of all allotment areas corresponds to seamless coverage of Germany. All network operators are obliged to implement the networks within a time frame of 5 to 8 years in order to provide coverage of more than 80% of the total population.
At present about 85% of the German households are located within the service area of T-DAB transmitter networks. However, the market penetration of receiver equipment is still low. In order to improve the situation, several activities are underway. An "Initiative for Digital Broadcasting" (Initiative Digitaler Rundfunk) chaired by the Federal Ministry of Economics and Labour investigates T-DAB issues and aspects of improving the market development. Its efforts are complemented by the Digital Radio Plattform which endeavours to perform PR- and marketing activities for DAB.[6]
On 28 January 2008 the responsible government agency Kommission zur Ermittlung des Finanzbedarfs der Rundfunkanstalten (KEF) decided to freeze public funding of DAB due to its lack of success[7][8].
This deadlock was overcome by an agreement between public radio Deutschlandradio, several private radio stations and private broadcasting services provider Media Broadcast, to establish a nationwide DAB+ multiplex, which will commence broadcasting as of August 1, 2011. The new network will provide in-house reception in its service areas, whereas the established DAB network used weaker transmission strengths which usually only allowed for outdoors reception.
On May 2008 the launch of Africa’s first DMB mobile TV commercial took place in Ghana with FonTv. The service, which uses DMB technology, is operated by Black Star TV, who have completed nearly a year of trials before launching full commercial operations countrywide.
In Greece there is DAB-T service only in Athens at present time by Hellenic Broadcasting Corporation (ERT).
DAB trials have been conducted on the L Band (1998)[9] and on Band III (2004).[10] The trials involved all three radio broadcasters: RTHK (Radio Television Hong Kong), HKCB (Commercial Radio Hong Kong), and MB (Metro Radio Hong Kong).
The application of digital audio broadcasting licences was opened on February 2010 and to be ended on April; services were expected to be launched in the city by late 2010 or early 2011.[11]
On 24 March 2011, Digital Broadcasting Corporation Hong Kong[12], Metro Broadcast Corporation and Phoenix U Radio were granted 12-year audio broadcasting licences respectively by the Hong Kong Government.[13] All of them use DAB+ as the broadcasting technology.
Indonesia began DAB trial transmissions on August 2006. There are four DAB radio stations: Prambors, Ramako, Sonora and I-Radio. On the trial period, DAB radios use 10D VHF frequency.
Ireland's public service broadcaster and owner of the sole national transmission network, RTÉ, launched its DAB service to the East and North-East on 30 November 2006, using Channel 12C.[14] It initially began with six stations (four live), consisting initially of the RTÉ radio stations. Currently, it carries the four RTÉ stations, an occasional simulcast of the Mediumwave version of RTÉ Radio 1, and four new RTÉ digital-only services, as well as some trial services.
Nearly a year previously, on 20 December 2005, RTÉ announced that DAB trials would begin along the east coast on 1 January 2006. This date was 80 years after Radio Éireann (RTÉ's predecessor) began. By 5 January, two transmitters, Clermont Carn and Three Rock Mountain, were transmitting a single multiplex on channel 12C, carrying 6 channels - RTÉ Radio 1, RTÉ 2fm, RTÉ lyric fm, RTÉ Raidió na Gaeltachta, Today FM and the World Radio Network, all at 192 kbit/s. In May, this was reduced to just RTÉ Radio 1 and RTÉ 2FM at 160 kbit/s. These test DAB transmissions ceased on 13 July and DAB remained off-air until the public commencement that November.
A second multiplex appeared in Dublin (Three Rock Mountain transmitter) on block 12A in March 2007 carrying Today FM, Q102, Phantom 105.2, FM104 and 98FM. Today FM was removed from the RTÉ mux on 12C at this time.
DAB development was limited by the lack of Band III frequencies until the GE06 Conference earlier this year. Prior to GE06 (formerly known as RRC-06), the Republic of Ireland had only two channels allocated to DAB: 12C to RTÉ for the entire country and 12A allocated to commercial broadcasting. However, roll-out using the lower channels made available after the conference will most likely be limited until the RTÉ television broadcasts in Band III are moved to UHF.
Local radio franchise areas have been allocated an L band DAB channel, as well as any counties which do not match radio franchises. L band capable receivers are relatively rare in Europe, although are the standard in Canada and other countries.
In band III VHF (174-220 MHz) in some areas it's possible to hear 3 groups of radio stations:
Others radio stations are also available in certain areas (like RAS and SSR radio stations are available, respectively, in South Tyrol and in Lombardy).
On 1 February 2007 public radio broadcaster RAI started experimentation of broadcasting in T-DMB in some areas of the country.
On 25 July 2007 Club Dab Italia started experimentation of broadcasting in DAB+. On the 4th of December, the Italian regulator formally approved DAB+ digital radio to launch in Italy.[15]
T-DAB spectrum licenses have been awarded in March 2006. In August 2005, the Malta Communications Authority (MCA) together with the Ministry for Competitiveness and Communications published Malta's policy and implementation strategy on T-DAB. Digi B Network Ltd. was the highest bidder for all the 4 frequency blocks available, and was granted a license in March 2006, although the frequency blocks still needed to be coordinated between neighbouring countries. Digi B started commercial rollout in 2008, using the DAB system.[16]
June 2010, the independent regulator for the Malaysian communications industries, Malaysian Communications and Multimedia Commission (MCMC) officially awarded three blocks of L-Band Spectrum (1452.960 MHz, 1454.672 MHZ and 1456.384 MHz) to Asia Media.[17][18] The company plans to utilize the allocated frequencies to deploy a Terrestrial Digital Multimedia Broadcasting (T-DMB) network and operate up to twelve programme channels including digital TV, radio and data channels.[19]
Currently (RTM) Radio Television Malaysia is conducting a DAB+ trial with 15 radio channels.
DAB digital radio is broadcast over the Monaco principality. Three radio stations are available on the Riviera, and Monegasques have received DAB digital radio technology since spring 2005.
In Mexico broadcasters are interest in DAB+ or DMB as part of a multi-standard market. The Mexican regulator, COFETEL, is expected to announce a decision on the digital radio standard by the end of 2009.
In March 2005, following criticism from politicians from all parties, the Dutch Minister of Economic Affairs Laurens Jan Brinkhorst announced that The Netherlands has postponed plans to continue rolling out DAB, and will instead evaluate newer technologies. The new technologies which will be assessed include the new version of DAB DRM+ and DVB-H, and are more efficient than the current version of DAB, so it is likely that The Netherlands will end up using an upgraded version of DAB based on the AAC+ codec.
Netherlands Public Broadcasting has been transmitting in block 12C since 2004. Nine radio channels are available, including a non-stop Top 2000 channel and a continuous repetition of the last news bulletin. Territorial coverage of the Netherlands is currently limited, but 70% of the population is covered.
New Zealand has been trialling DAB since November 2006 in Wellington and west Auckland but wants to use the new DAB+ standard once testing is finished.
Around 20 stations are available on DAB, including all of NRKs broadcast channels and commercial P4, and SBS radio with four national commercial channels. NRK has several DAB channels, some which are exclusive to DAB and some which are available via the FM net in larger cities. During 2007 NRK launched several DAB-only stations. As the DAB network is expanded, some local radio stations are licenced to broadcast via DAB, and Radio Nova is currently operating a DAB+ test transmission.
Norway started test transmission of DMB TV broadcasts in 2009 [20]
The first DAB test transmissions were started in the middle of the 1990s. NRK Alltid klassisk started broadcasting in June 1995 and was the world's first all-digital around-the-clock radio, with non-stop classical music. NRK Alltid nyheter (news radio) started broadcasting in 1997, at a time when there were only about 25 DAB receivers in Norway.
DAB radio in Norway is divided into a national multiplex on channel 12D, and several regional multiplexes. The regional multiplexes broadcast versions of NRK P1 with regional programming and several other NRK channels which do not fit on the national band.
As of December 2006 about 70% of the population is potentially covered by DAB, but FM is by far the most common method of radio distribution. In Norway the DAB market was very small until the close of 2004, with few available receivers and little demand. Since Christmas 2004, the market has been growing; more than 290,000 have been sold through since the introduction.. As of January 2009, DAB is experiencing a slow but steady increase in popularity, and approximately 17% of the population can receive DAB.[21]
Norwegian government have let DAB coverage expand to 80% of the population, with two multiplexes available in all areas. Norway aims at reaching full national DAB coverage before 2014. The Norwegian Minister of Culture stated that FM-band broadcasting are planned to be switched off when digital radio in total (not only DAB, but also streaming web-radio) reaches 50% penetration of the market, and will during 2010 publish a road map for digital radio.[22]
In the summer of 2010 four new channels were introduced on the national multiplex. The channels Radio Norge, P5, NRJ and Radio1 was already broadcasting on FM in selected areas.[23] Also, Radio Nova are to start trial transmission of DAB+ in the Oslo area.[24]
Polskie Radio, the Polish public sound broadcaster, had to stop broadcasting its 4 audio services in Band II DAB Block (105,008 MHz), which covered 8% of the Polish population, due to the lack of electromagnetic compatibility with the existing VHF FM services. In October 2001 the test transmission was resumed in Warsaw on the DAB Block 10B. It is foreseen that this transmission will form the first part of the SFN covering Central Poland.
In January 2004 Poland's Office of Telecommunications and Post Regulation (URTiP) presented a new concept of a frequency planning in Band III. This idea is based on full exploitation of the spectrum by digital sound and television broadcasting after analogue switch off and changing channel spacing from 8 to 7 MHz. This accommodates three national T-DAB layers and one national DVB-T multiplex at the same time.
Radio Wroclaw, a public broadcaster, and TP Emitel, a national infrastructure operator, launched the country’s first DAB+ trial in May 2009 in the city of Wroclaw. Another trial has started in Polish capital city, Warsaw, in November 2009. It is expected that following the tests stakeholders will look towards launching commercial services.
Only the public radio stations from Radiodifusão Portuguesa are broadcast in DAB. The service started in August 1998 on tests within the Expo 98. RDP Antena 1, RDP Antena 2, RDP Antena 3, RDP Internacional, RDP África and the RDP regional stations are all broadcast on the single 12B channel on the majority of the country, especially on the district capitals and the main routes. Of the initially planned 74 transmitters, only 44 were installed, covering 72% percent of the country in 2006.
In 2004 Rádio Renascença and RFM joined the 12B channel, overloading the system and having no better quality than FM. The Portuguese government is constantly delaying this matter and now better options are at stake, like the DAB+ and DMB, with better performance and they can use the existing transmitters instead of replacing them for DAB's.
Radiodifusão Portuguesa plans to end the service in April 2011, due to lack of public interest, and non-existing legal framework for the inclusion of further radios on the platform.
As of summer 2005, in Bucharest there is a single emitter that broadcasts three radio stations multiplexed on channel 12A (223,936 MHz - Band III). These digital radio stations (two public service and one commercial) are: Radio România Actualităţi, Radio România Muzical, Radio 21. Other 2 stations signal is also available Radio Romantic and Pro FM, but no actual audio content is present [25]
There are no T-DAB transmitters working at present time, but two licences for commercial T-DAB broadcasting services supposed to be granted now, because of existing interest and demands.
In Singapore, MediaCorp's DigitalRadio was launched on 19 November 1999. Using the Eureka 147 DAB system, DigitalRadio provides six digital-only stations and eight simulcast FM services, along with images and text to supplement the audio. Singapore was the first country to reach full DAB coverage.[26] Mediacorp has announced that its Digital radio services are set to end with effect from 1 December 2011. [27]
Spain had a DAB population coverage of 51% from April 2001 until June 2011. With the approval of Royal Decree 802/2011 on 10th June, minimum population coverage decreased to 20%[28]. There are three national multiplexes: public (192 kbit/s each, but the public classical music radio station has 224 kbit/s stereo, REE has 160 kbit/s mono), and commercial (160 kbit/s stereo) radio stations, with 6 services each[29]. Two radio stations are DAB exclusive but have poor programming (music jukebox)[30].
Catalunya Ràdio broadcast four simulcast radio stations in DAB with a bitrate of 192 kbit/s. It broadcast two exclusive radio stations in DAB: Catalunya Digital 1 and 2 with 192 kbit/s each[31]. Catalunya Digital 1 offered music in Catalan and Catalunya Digital 2 offered varied music with the inclusion in the DLS of the artist and the title of the song you're listening now[32]. Catalunya Ràdio covered 85% of the population between 2001 and 2006[33], but then started to switch-off DAB transmitters (first Rocacorba in December 2006[34], then Alpicat[35], Montcaro and finally La Mussara in June 2007[36]), leaving only Collserola on. Until 4th November 2008 when the last transmitter broadcasting Catalunya Ràdio was disconnected, breaking the law[37].
In Slovakia there is no T-DAB service in air at present time, even though all major TV transmitters which have been in collision with VHF T-DAB frequencies moved to UHF band.
Swedish radio is currently offering 7 channels DAB-transmissions and cover 35-40% of the population, mainly in the larger cities.
DAB transmissions in Sweden began with tests as early as 1995, and were later expanded to cover larger parts of the Swedish population.
On 14 December 2005 the Swedish Culture minister, Leif Pagrotsky, announced that the Swedish government was freezing investment in DAB, citing that DAB was very expensive to transmit and that cheaper digital radio systems should be investigated, and digital radio should also be transmitted via the Internet and via the digital terrestrial TV system. The government decision were quickly criticised by Swedish broadcasters.
On the 21 December 2006, the Swedish Government renewed Swedish Radio's license to transmit DAB broadcasts in Sweden. The license also allows Swedish Radio to test technologies as DAB version 2 and DMB.[38][39] DAB transmissions continue with coverage of Stockholm and other cities.
During June 2008 the Swedish workgroups within Radio- och TV-verket published their report "Framtidens Radio", recommending DAB+ as the best platform for digital radio. The report where endorsed by both corporate and governmental broadcasters.
The coverage map is now nationwide (2009 = over 92% of the population). All the regions are covered by the DAB/DAB+ network. The tunnels along the main traffic arteries are mostly not covered at the end of 2009.
World Radio Switzerland (WRS - national media broadcast in English) can be received in all the country (DAB in French and Italian speaking areas, DAB+ in other regions). WRS is part of the Swiss Broadcasting Corporation, Switzerland’s national public broadcaster.[40]
The commercial broadcaster in Taiwan, Super FM, plans to launch DAB+ services with three audio channels and one DMB multi-media video based service. Six commercial broadcasters have also been granted licences, but being cancelled due to unable launch trial. Now Super FM is the only remaining station licensed in northern Taiwan.
TRT, the Turkish Broadcasting Corporation, launched DAB test transmissions in Band III in Ankara on the 1st March 2002. One transmitter covers the Ankara city centre and reaches approximately 2 million people.
An SFN (Single Frequency Network) application had been planned in Ankara with the addition of a 1Kw new transmitter. In order to increase the awareness of DAB, the new 1Kw transmitter will be transferred to Istanbul, the biggest city of Turkey.
Broadtech SC (a subsidiary of VTV) has had a DMB trial on-air in Hanoi since September 2008. VTV is planning to launch a commercial DMB service in September 2009.
Experimental transmissions by the BBC started in 1990 with permanent transmissions covering London in September 1995. In September 1997 the BBC announced its national DAB rollout plans and soon reached 65% coverage. In 2006 the majority of national broadcasters all broadcast on DAB (as well as traditional AM/FM).
The public service broadcaster, the BBC, has been promoting its DAB Digital Radio stations since September 1995 and at present (2006) covers about 88% of the population, including the major motorway network. Progress beyond this figure seems to be slow, leaving some several million of the UK population who still do not know when they will be able to receive DAB.
By the end of 2009, 10 million DAB radios had been sold in the UK.[41] and 26.5% of all radio's 1.58 billion listening hours are on a digital platform [42] Access to a DAB receiver was up 11.1% in 2011 to 20.2 million adults versus 2010.[43] However the partial take-up of digital radio and the still almost universal presence of FM receivers in homes and particularly in cars, has led to the planned date for switching off the analogue transmitters by 2015 being questioned.[44]
The BBC national DAB multiplex contains a number of different services, including Radios 1-5, and digital-only services such as Radio Five Live Sports Extra, 6 Music, 1Xtra and BBC Radio 4 Extra, as well as an EPG.
The Digital One national commercial multiplex began broadcasts on 15 November 1999 with 69% coverage and since then its DAB network has always been more extensive than the BBC's. It contains eight audio stations, an EPG and an experimental video service for mobile phones which was launched in October 2006. Digital One also developed along with Frontier Silicon a low cost silicon chip used in the majority of receivers and is directly responsible for DAB receiver prices falling below £100 in 2002, and as little as £30 in 2006. As a result of this, DAB portable radios are now outselling their analogue counterparts at the highstreet chain Currys.digital (formerly Dixons). It's quite common that you can buy a radio that can receive band 2 (analogue) and Band 3 VHF (digital) and switch between the two. In the DAB car radios the main technology is SDR, such as EtherWaves software on ADI's DSPs.
In addition to the national services, by the end of 2004 there were 48 local and regional radio multiplexes, providing over 250 commercial and 34 BBC stations. For example, in London there are already more than 51 different digital stations available. Further regional and local multiplexes are being planned by Ofcom, the UK regulator. The UK has by far the largest number of DAB stations broadcasting in the world, the highest numbers of listeners to these services [2].