Digital multimedia broadcasting

Last updated
Live DMB broadcast on an iriver device during trials in Munich, Germany (2007) Live television on this iRiver DAB DMB device.jpg
Live DMB broadcast on an iriver device during trials in Munich, Germany (2007)
A DMB television broadcast received on a mobile device in South Korea DMB Phone.jpg
A DMB television broadcast received on a mobile device in South Korea

Digital multimedia broadcasting (DMB) is a digital radio transmission technology developed in South Korea [1] [2] [3] as part of the national IT project for sending multimedia such as TV, radio and datacasting to mobile devices such as mobile phones, laptops and GPS navigation systems. This technology, sometimes known as mobile TV, should not be confused with Digital Audio Broadcasting (DAB) which was developed as a research project for the European Union.

Contents

DMB was developed in South Korea as the next generation digital technology to replace FM radio, [4] but the technological foundations were laid by Prof. Dr. Gert Siegle and Dr. Hamed Amor at Bosch in Germany. [5] 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 has also some similarities with its former competing mobile TV standard, DVB-H. [6]

S-DMB

T-DMB

T-DMB is made for terrestrial transmissions on band III (VHF) and L (UHF) frequencies. DMB is unavailable in the United States because those frequencies are allocated for television broadcasting (VHF channels 7 to 13) and military applications. USA is adopting ATSC-M/H for free broadcasts to mobiles, and for a time, Qualcomm's proprietary MediaFLO system. 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 an MPEG transport stream (MPEG-TS). The stream is forward error corrected by Reed Solomon encoding and the parity word is 16 bytes long. 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, the DMB modem uses OFDM-DQPSK modulation. A single-chip T-DMB receiver is also provided by an MPEG 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, 1seg, and MediaFLO. [7]

Smart DMB

Smart DMB started in January 2013 in South Korea. Smart DMB has a VOD service and quality has been improved from 240p to 480p. Smart DMB is built in many Korean smartphones starting with the Galaxy Grand in January 2013. [8]

HD DMB

HD DMB started in August 2016 in South Korea. HD DMB has been improved from 240p to 720p. It uses HEVC.5 codec. There are currently[ when? ] 6 HD DMB stations in Seoul. Smartphones integrated Qualcomm Snapdragon 801 or higher received firmware upgrade to support HD DMB.

Countries using DMB

Currently, DMB is being put into use in a number of countries, although mainly used in South Korea. Also see list of Countries using DAB/DMB.

South Korea

In 2005, South Korea became the world's first country to start S-DMB and T-DMB service on May 1 and December 1, respectively. [9] [10] In 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 (6 MHz raster). In October 2007, South Korea added broadcasting channel MBCNET to the DMB channel. But in 2010, this channel changed tnN go. In 2009 there were eight DMB video channels in Seoul, and six in other metropolitan cities. As of April 2013, S-DMB service in South Korea consists of 15 TV channels, 2 radio channels and 6 data channels. [11]

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

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 to selected regions.

Around one million receivers have been sold as of June 2006. 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. [12]

Receivers are integrated in car navigation systems, mobile phones, portable media players, laptop computers and digital cameras. In mid-August 2007, Iriver, a multimedia and micro-technology company released their "NV", which utilizes South Korea's DMB service.

Since the advent of smartphones DMBs have been made available on phones with receivers through smartphone applications, most of which come pre-installed in phones made and sold in South Korea.

Other countries

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

DMB in automobiles

T-DMB works flawlessly in vehicles traveling up to 300 km/h.[ citation needed ] In tunnels or underground areas, both television and radio broadcast is still available, though DMB may skip occasionally. In South Korea, some long-distance buses adopted T-DMB instead of satellite TV such as Sky TV. It works quite well even though the resolution is 240p, lower than satellite. In comparison, satellite is usually 480p or higher.[ citation needed ]

See also

Related Research Articles

<span class="mw-page-title-main">Digital television</span> Television transmission using digital encoding

Digital television (DTV) is the transmission of television signals using digital encoding, in contrast to the earlier analog television technology which used analog signals. At the time of its development it was considered an innovative advancement and represented the first significant evolution in television technology since color television in the 1950s. Modern digital television is transmitted in high-definition television (HDTV) with greater resolution than analog TV. It typically uses a widescreen aspect ratio in contrast to the narrower format (4:3) of analog TV. It makes more economical use of scarce radio spectrum space; it can transmit up to seven channels in the same bandwidth as a single analog channel, and provides many new features that analog television cannot. A transition from analog to digital broadcasting began around 2000. Different digital television broadcasting standards have been adopted in different parts of the world; below are the more widely used standards:

<span class="mw-page-title-main">Digital Audio Broadcasting</span> Digital radio standard

Digital Audio Broadcasting (DAB) 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 organisation. The standard is dominant in Europe and is also used in Australia, and in parts of Africa and Asia; as of 2022, 55 countries are actively running DAB broadcasts.

<span class="mw-page-title-main">DVB</span> Open standard for digital television broadcasting

Digital Video Broadcasting (DVB) is a set of international open standards for digital television. DVB standards are maintained by the DVB Project, an international industry consortium, and are published by a Joint Technical Committee (JTC) of the European Telecommunications Standards Institute (ETSI), European Committee for Electrotechnical Standardization (CENELEC) and European Broadcasting Union (EBU).

MPEG-1 Audio Layer II or MPEG-2 Audio Layer II is a lossy audio compression format defined by ISO/IEC 11172-3 alongside MPEG-1 Audio Layer I and MPEG-1 Audio Layer III (MP3). While MP3 is much more popular for PC and Internet applications, MP2 remains a dominant standard for audio broadcasting.

DVB-T, short for Digital Video Broadcasting – Terrestrial, is the DVB European-based consortium standard for the broadcast transmission of digital terrestrial television that was first published in 1997 and first broadcast in Singapore in February, 1998. This system transmits compressed digital audio, digital video and other data in an MPEG transport stream, using coded orthogonal frequency-division multiplexing modulation. It is also the format widely used worldwide for Electronic News Gathering for transmission of video and audio from a mobile newsgathering vehicle to a central receive point. It is also used in the US by Amateur television operators.

Integrated Services Digital Broadcasting is a Japanese broadcasting standard for digital television (DTV) and digital radio.

<span class="mw-page-title-main">ATSC standards</span> Standards for digital television in the US

Advanced Television Systems Committee (ATSC) standards are an International set of standards for broadcast and digital television transmission over terrestrial, cable and satellite networks. It is largely a replacement for the analog NTSC standard and, like that standard, is used mostly in the United States, Mexico, Canada, South Korea and Trinidad & Tobago. Several former NTSC users, such as Japan, have not used ATSC during their digital television transition, because they adopted other systems such as ISDB developed by Japan, and DVB developed in Europe, for example.

<span class="mw-page-title-main">Digital Radio Mondiale</span> Digital radio broadcasting standard

Digital Radio Mondiale is a set of digital audio broadcasting technologies designed to work over the bands currently used for analogue radio broadcasting including AM broadcasting—particularly shortwave—and FM broadcasting. DRM is more spectrally efficient than AM and FM, allowing more stations, at higher quality, into a given amount of bandwidth, using xHE-AAC audio coding format. Various other MPEG-4 codecs and Opus are also compatible, but the standard now specifies xHE-AAC.

Digital radio is the use of digital technology to transmit or receive across the radio spectrum. Digital transmission by radio waves includes digital broadcasting, and especially digital audio radio services.

Digital terrestrial television is a technology for terrestrial television where television stations broadcast television content in a digital format. DTTV is a major technological advance over analog television, and has largely replaced analog television broadcast, which had been in common use since the middle of the 20th century. Test broadcasts began in 1998 with the changeover to DTTV, also known as the Analog Switchoff (ASO) or Digital Switchover (DSO), which began in 2006 and is now complete in many countries. The advantages of digital terrestrial television are similar to those obtained by digitizing platforms such as cable TV, satellite, and telecommunications: more efficient use of radio spectrum bandwidth, provision of more television channels than analog, better quality images, and potentially lower operating costs for broadcasters.

<span class="mw-page-title-main">Television in Malaysia</span>

Malaysian television broadcasting was introduced on 28 December 1963. Colour television was introduced on 28 December 1978. Full-time colour transmissions were officially inaugurated on New Year's Day 1982. There are currently 16 national free-to-air terrestrial television channels in Malaysia and 3 national pay subscription television operators in Malaysia.

DVB-H is one of three prevalent mobile TV formats. It is a technical specification for bringing broadcast services to mobile handsets. DVB-H was formally adopted as ETSI standard EN 302 304 in November 2004. The DVB-H specification can be downloaded from the official DVB-H website. From March 2008, DVB-H is officially endorsed by the European Union as the "preferred technology for terrestrial mobile broadcasting". The major competitors of this technology are Qualcomm's MediaFLO system, the 3G cellular system based MBMS mobile-TV standard, and the ATSC-M/H format in the U.S. DVB-SH now and DVB-NGH in the future are possible enhancements to DVB-H, providing improved spectral efficiency and better modulation flexibility. DVB-H has been a commercial failure, and the service is no longer on-air. Ukraine was the last country with a nationwide broadcast in DVB-H, which began transitioning to DVB-T2 during 2019.

<span class="mw-page-title-main">MediaFLO</span> Media transmission technology developed by Qualcomm

MediaFLO was a technology developed by Qualcomm for transmitting audio, video and data to portable devices such as mobile phones and personal televisions, used for mobile television. In the United States, the service powered by this technology was branded as FLO TV.

S-DMB (Satellite-DMB) was a hybrid version of the Digital Multimedia Broadcasting. The S-DMB used the S band (2170-2200 MHz) of IMT-2000. and delivered around 18 channels at 128 kbit/s in 15 MHz. It incorporated a high power geostationary satellite, the MBSat 1. For outdoor and light indoor coverage is integrated with a terrestrial repeater network for indoor coverage in urban areas.

Mobile television is television watched on a small handheld or mobile device, typically developed for that purpose. It includes service delivered via mobile phone networks, received free-to-air via terrestrial television stations, or via satellite broadcast. Regular broadcast standards or special mobile TV transmission formats can be used. Additional features include downloading TV programs and podcasts from the Internet and storing programming for later viewing.

IP over DVB implies that Internet Protocol datagrams are distributed using some digital television system, for example DVB-H, DVB-SH, DVB-T, DVB-S, DVB-C or their successors like DVB-T2, DVB-S2, and DVB-C2. This may take the form of IP over MPEG, where the datagrams are transferred over the MPEG transport stream, or the datagrams may be carried in the DVB baseband frames directly, as in GSE.

ETSI Satellite Digital Radio describes a standard of satellite digital radio. It is an activity of the European standardisation organisation ETSI.

<span class="mw-page-title-main">Countries using DAB/DMB</span>

The radio technology known as Digital Audio Broadcasting, and its TV sibling, Digital Multimedia Broadcasting (DMB), is being operated in several regions worldwide, either in the form of full services, or as feasibility studies.

References

  1. ↑ "Korea's Terrestrial DMB: Germany to begin broadcast this May". ZDNet Korea. Retrieved 2010-06-17.
  2. ↑ "picturephoning.com: DMB". Textually.org. Archived from the original on 2010-08-09. Retrieved 2010-06-17.
  3. ↑ "South Korea : Social Media 답변 내용 : 악어새 - 리포트월드". Reportworld.co.kr. Archived from the original on 2009-08-17. Retrieved 2010-06-17.
  4. ↑ "The Introduction of DMB in Korea" (PDF). Ericemoon.googlepages.com. Archived from the original (PDF) on 2009-03-26. Retrieved 2010-06-17.
  5. ↑ "Sichere Bewegtbildübertragung zum mobilen Teilnehmer". deutscher-zukunftspreis.de. 1998. Archived from the original on 2013-06-28. Retrieved 2019-11-27.
  6. ↑ "T-DMB". Eng.t-dmb.org. Archived from the original on 2010-02-13. Retrieved 2010-06-17.
  7. ↑ "ITU approves Mobile TV Standards". The Korea Times. 16 December 2007. Retrieved 2010-06-17.
  8. ↑ "Smart DMB starting with Samsung Phones". 아이뉴스24 (iNews 24). Retrieved 2013-01-20
  9. ↑ "AsiaMedia :: KOREA: Cell phone-based broadcasting starts". Asiamedia.ucla.edu. Archived from the original on 2011-09-28. Retrieved 2010-06-17.
  10. ↑ "AsiaMedia :: KOREA: KBS to start terrestrial mobile television services next month". Asiamedia.ucla.edu. 2005-11-22. Archived from the original on 2010-07-21. Retrieved 2010-06-17.
  11. ↑ "South Korea". WorldDMB. Archived from the original on 10 July 2017. Retrieved 12 July 2015.
  12. ↑ DMB users shout in the metro coming home, Daily economics
  13. ↑ "Norway launches mobile TV via DMB". Broadbandtvnews.com. 2009-05-18. Retrieved 2010-06-17.
  14. ↑ "DAB Ensembles Worldwide: Norway". wohnort.org. Retrieved 2023-04-11.
  15. ↑ Broadband TV news: MFD hands back German T-DMB licence, May 1, 2008
  16. ↑ "Country Information for DAB, DAB+ and DMB -France (WorldDMB)". Worlddab.org. 2008-01-18. Archived from the original on 2010-06-25. Retrieved 2010-06-17.
  17. ↑ WorldDAB - Country Information - France Archived 2015-02-20 at the Wayback Machine Worlddab.org, on 2017-06-14
  18. ↑ "Country Information for DAB, DAB+ and DMB -China (WorldDMB)". Worlddab.org. Archived from the original on 2010-08-15. Retrieved 2010-06-17.
  19. ↑ "Country Information for DAB, DAB+ and DMB -Ghana (WorldDMB)". Worlddab.org. Archived from the original on 2011-07-22. Retrieved 2010-06-17.
  20. ↑ Emerce Digitale omroep gaat concurrentie aan met KPN MobielTV, Februari 12, 2009
  21. ↑ "RAIWay". RAIWay. Archived from the original on 2011-07-22. Retrieved 2010-06-17.
  22. ↑ Webteam. "Web TV and T-DMB programmes". Vatican Radio. Archived from the original on 2010-03-07. Retrieved 2010-06-17.
  23. ↑ "CBC/Radio-Canada Conducts Field Trials with Mobile Broadcast Multimedia".
  24. ↑ 박, 창욱. "캄보디아, 韓 지상파DMB 국가표준 채택". n.news.naver.com.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.