Digital Multimedia Broadcasting

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DMB in Korea
List of digital video broadcast standards
DVB family (Europe)
DVB-S (satellite)
DVB-T (terrestrial)
DVB-C (cable)
DVB-H (handheld)
ATSC family (North America)
ATSC (terrestrial/cable)
ATSC-M/H (mobile/handheld)
ISDB family (Japan/Brazil)
ISDB-S (satellite)
ISDB-T (terrestrial)
ISDB-C (cable)
SBTVD/ISDB-TB (Brazil)
Chinese Digital Video Broadcasting standard
DMB-T/H (Terrestrial/Handheld)
ADTB-T (Terrestrial)
CMMB (Handheld)
ABS-S (satellite)
DMB Family (Korean)
T-DMB (terrestrial)
S-DMB (satellite)
Codecs
Video
Audio
Frequency bands
VHF
UHF
SHF

Digital Multimedia Broadcasting (DMB) is a South Korean technology used in digital radio transmission system for sending multimedia (radio, TV, and datacasting) to mobile devices such as mobile phones. This technology, sometimes known as "mobile TV", is an offshoot of Digital Audio Broadcasting which was originally developed as a research project for the European Union (Eureka project number EU147). DMB was developed in South Korea under the national IT project, originally as the next generation digital technology to replace the FM radio.[1] The world's first official mobile TV service started in South Korea in May 2005, although trials were available much earlier. It can operate via satellite (S-DMB) or terrestrial (T-DMB) transmission. DMB is based on the Eureka 147 Digital Audio Broadcasting (DAB) standard, and has some similarities with the main competing mobile TV standard, DVB-H.[2]

Contents

[edit] T-DMB

Like DAB, T-DMB is made for transmissions on radio frequency bands band III (VHF) and L (UHF), for terrestrial. Because the United States and Canada still allocate the first band for television broadcasting (VHF channels 7 to 13) and the United States reserves the L band for military applications, DMB is still unavailable in North America. Qualcomm's MediaFLO is a proprietary system used there instead. In Japan, 1seg is the standard, using ISDB.

T-DMB uses MPEG-4 Part 10 (H.264) for the video and MPEG-4 Part 3 BSAC or HE-AAC V2 for the audio. The audio and video is encapsulated in MPEG-2 TS. The stream is RS encoding and the parity word is 16 bytes length. There is convolutional interleaving made on this stream, then the stream is broadcast in data stream mode on DAB. In order to diminish the channel effects such as fading and shadowing, DMB modem uses OFDM-DQPSK modulation. A single-chip T-DMB receiver is also provided by an MPEG-2 transport stream demultiplexer. DMB has several applicable devices such as mobile phone, portable TV, PDA and telematics devices for automobiles.

T-DMB is an ETSI standard (TS 102 427 and TS 102 428). As of December 14, 2007, ITU formally approved T-DMB as the global standard, along with three other standards, like DVB-H, OneSeg, and MediaFLO.[3]

[edit] Deployment

Currently, DMB is being put into use in a number of countries, although mainly used in South Korea.

[edit] South Korea

In 2005, South Korea started S-DMB and T-DMB service on May 1 and December 1, respectively.[4][5]

As of December 2006, T-DMB service in South Korea consists of, 7 TV channels, 12 radio channels, and 8 data channels. These are broadcast on six multiplexes in the VHF band on TV channels 8 and 12 (6MHz faster).

As of April 2007, S-DMB service in South Korea consists of 15 TV channels and 19 radio channels and 3 data channels.

S-DMB service in South Korea is provided on a subscription basis through TU Media and is accessible throughout the country. T-DMB service is provided free of charge, but access is limited in selected regions.

Around one million receivers have been sold as of June 2006. Receivers are integrated in car navigation systems, mobile phones, portable media players, laptop computers and digital cameras.

South Korea has had Full T-DMB services including JSS (Jpeg Slide Show), DLS (Dynamic Label Segment), BWS, and TPEG since 2006.

In Mid August 2007, Iriver, a multimedia and micro-technology company released their "NV", which utilizes South Korea's DMB service.

In October 2007, South Korea added broadcasting channels "MBCNET" to the DMB channel. There are now eight DMB video channels in Seoul and six in other metropolitan cities.

14 million DMB receivers were sold including T-DMB and S-DMB in South Korea, and 40% of the new cell phones have the capability to see DMB.[6]

[edit] DMB in automobiles

See also: Software-defined radio and Car audio

T-DMB works flawlessly in vehicles traveling up to 120 km/h. In tunnels or underground areas, both TV and Radio broadcast is still available, though DMB may skip occasionally. Fortunately, the broadcast recovers quickly.

[edit] Europe and some other countries

Some T-DMB trials are currently planned or available around Europe and other countries:

  • Germany's 'Mobiles Fernsehen Deutschland' (MFD) launched the commercial T-DMB service "Watcha" in June 2006, in time for the World Cup 2006, marketed together with Samsung's P900 DMB Phone, the first DMB Phone in Europe. It was stopped in April 2008 as MFD is now favouring DVB-H, the European standard.[7]
  • The Netherlands: MFD, T-Systems and private investors are planning a DMB service under the name Mobiele TV Nederland. Callmax will also deploy a DMB service on the L-Band frequency in the Netherlands.[8].
  • France is currently running a trial in Paris.
  • Indonesia is currently running a trial in Jakarta.
  • Norway (NRK) is currently running a trial in Trondheim, Norway. August 15, 2008 NRK, TV2 and MTG announced that Norges Mobil-TV AS will run trials with nine channels in the greater Oslo within two years.[9]
  • Italy ran a 6-month trial in some areas, they decided to cover more than 50% of the population before the end of 2007.
  • China is planning to do DMB service during the 2008 Olympics.
  • Ghana is currently running a trial in Accra on Onetouch mobile network.
  • Canada has been running trials since 2006 in Ottawa, Toronto, Vancouver and Montreal, done by CBC/Radio-Canada.
  • Malaysia has been running trials since 2008 in KL, done by TV3/MPB.

[edit] See also

[edit] References

  1. ^ The Introduction of DMB in Korea
  2. ^ T-DMB
  3. ^ [1] ITU approves Mobile TV Standards]
  4. ^ http://www.asiamedia.ucla.edu/article.asp?parentid=23866
  5. ^ http://www.asiamedia.ucla.edu/article.asp?parentid=34172
  6. ^ DMB users shout in the metro coming home, Daily economics
  7. ^ Broadband TV news: MFD hands back German T-DMB licence, May 1, 2008
  8. ^ Emerce Digitale omroep gaat concurrentie aan met KPN MobielTV, Februari 12, 2009
  9. ^ http://www.amobil.no/artikler/samarbeider_om_mobil-tv/54840

[edit] External links

[edit] Official

[edit] Other

Related websites


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