DVB-T explained

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[1] and first broadcast in Singapore in February 1998.[2] [3] [4] [5] [6] [7] [8] This system transmits compressed digital audio, digital video and other data in an MPEG transport stream, using coded orthogonal frequency-division multiplexing (COFDM or OFDM) modulation. It is also the format widely used worldwide (including North America) 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.

Basics

Rather than carrying one data carrier on a single radio frequency (RF) channel, COFDM works by splitting the digital data stream into a large number of slower digital streams, each of which digitally modulates a set of closely spaced adjacent sub-carrier frequencies. In the case of DVB-T, there are two choices for the number of carriers known as 2K-mode or 8K-mode. These are actually 1,705 or 6,817 sub-carriers that are approximately 4 kHz or 1 kHz apart.

DVB-T offers three different modulation schemes (QPSK, 16QAM, 64QAM).

DVB-T has been adopted or proposed for digital television broadcasting by many countries (see map), using mainly VHF 7 MHz and UHF 8 MHz channels whereas Taiwan, Colombia, Panama and Trinidad and Tobago use 6 MHz channels. Examples include the UK's Freeview.

The DVB-T Standard is published as EN 300 744, Framing structure, channel coding and modulation for digital terrestrial television. This is available from the ETSI website, as is ETSI TS 101 154, Specification for the use of Video and Audio Coding in Broadcasting Applications based on the MPEG-2 Transport Stream, which gives details of the DVB use of source coding methods for MPEG-2 and, more recently, H.264/MPEG-4 AVC as well as audio encoding systems. Many countries that have adopted DVB-T have published standards for their implementation. These include the D-book in the UK, the Italian DGTVi,[9] the ETSI E-Book and the Nordic countries and Ireland NorDig.

DVB-T has been further developed into newer standards such as DVB-H (Handheld), which was a commercial failure and is no longer in operation, and DVB-T2, which was initially finalised in August 2011.

DVB-T as a digital transmission delivers data in a series of discrete blocks at the symbol rate. DVB-T is a COFDM transmission technique which includes the use of a Guard Interval. It allows the receiver to cope with strong multipath situations. Within a geographical area, DVB-T also allows single-frequency network (SFN) operation, where two or more transmitters carrying the same data operate on the same frequency. In such cases the signals from each transmitter in the SFN needs to be accurately time-aligned, which is done by sync information in the stream and timing at each transmitter referenced to GPS.

The length of the Guard Interval can be chosen. It is a trade-off between data rate and SFN capability. The longer the guard interval the larger is the potential SFN area without creating intersymbol interference (ISI).It is possible to operate SFNs which do not fulfill the guard interval condition if the self-interference is properly planned and monitored.

Technical description of a DVB-T transmitter

With reference to the figure, a short description of the signal processing blocks follows.

fs=

8
7

B

samples/s, where

B

is the channel bandwidth expressed in Hz.
Available bit rates (Mbit/s) for a DVB-T system in 8 MHz channels
ModulationCoding rateGuard interval
1/41/81/161/32
QPSK1/24.9765.5295.8556.032
2/36.6357.3737.8068.043
3/47.4658.2948.7829.048
5/68.2949.2169.75810.053
7/88.7099.67610.24610.556
16-QAM1/29.95311.05911.70912.064
2/313.27114.74515.61216.086
3/414.92916.58817.56418.096
5/616.58818.43119.51620.107
7/817.41819.35320.49121.112
64-QAM1/214.92916.58817.56418.096
2/319.90622.11823.41924.128
3/422.39424.88226.34627.144
5/624.88227.64729.27330.160
7/826.12629.02930.73731.668

Technical description of the receiver

The receiving STB adopts techniques which are dual to those ones used in the transmission.

Countries and territories using DVB-T or DVB-T2

Americas

Europe

Oceania

Asia

Africa

Countries and territories are available in DVB-T

Americas

Europe

Oceania

Asia

Africa

DVB-T/T2 switch-off

DVB-T/T2 is switched off in Switzerland and the Flemish part of Belgium. The EU plans to switch off DVB-T/T2 in its member states by 2030.

See also

References

External links

Notes and References

  1. Web site: ETSI EN 300 744 – Digital Video Broadcasting (DVB); Framing structure, channel coding and modulation for digital terrestrial television. October 2015. European Telecommunications Standards Institute. 66. https://web.archive.org/web/20160326000635/https://www.etsi.org/deliver/etsi_en/300700_300799/300744/01.06.02_60/en_300744v010602p.pdf. 26 March 2016. live.
  2. Web site: DATAONE LIMITED RESPONSE TO CONSULTATION PAPER ON DATACASTING. Infocomm Media Development Authority, Singapore.. https://web.archive.org/web/20200205010125/https://www.imda.gov.sg/-/media/imda/files/inner/archive/policies-and-regulation/policies_and_regulation_level3/fixed-wireless-broadband/response_-_dataone_limited.pdf. 5 February 2020. live.
  3. Web site: TELEVISION BROADCAST FOR SINGAPORE – March 3, 1998. 1999-10-08. live. https://web.archive.org/web/19991008210659/http://advent.com.sg/files/Pressrel-3.3.pdf. 1999-10-08. 2020-02-05.
  4. Web site: Advent Television launches the world's first digital terrestrial service in Singapore. 1999-10-08. live. https://web.archive.org/web/19991008193729/http://advent.com.sg/files/Pressrel-26.2.pdf. 1999-10-08. 2020-02-05.
  5. Web site: The Future is in Digital Broadcasting and that future is with Advent Television.. 2001-04-11. live. https://web.archive.org/web/20010411205700/http://www.advent.com.sg/technology.html. 2001-04-11. 2020-02-05.
  6. Web site: Press Release – April 27, 1998. 2000-06-04. live. https://web.archive.org/web/20000604105131/http://www.advent.com.sg/files/Pressrel-24.4.pdf. 2000-06-04. 2020-02-05.
  7. News: S'pore testing digital TV format. 5 March 1998. The Business Times. 5 March 1998. 4.
  8. News: SBA plans to launch digital TV after trying out systems. 9 March 1998. The Straits Times. 30.
  9. Web site: DGTVi – Per la Televisione Digitale Terrestre . 2008-07-30 . https://web.archive.org/web/20080419092227/http://www.dgtvi.it/stat/DGTVi/Page1.html . 2008-04-19 . ymd-all . usurped . it.
  10. Web site: About – DVB. 26 June 2016. https://web.archive.org/web/20130901023746/http://dvb.org/about_dvb/dvb_worldwide/bermuda/index.xml. 1 September 2013. dead.
  11. News: El Espectador. Colombia adopta el estándar europeo para la tv digital terrestre. es. 28 August 2008. 28 August 2008. https://web.archive.org/web/20190413185825/http://elespectador.com/node/34794/. 13 April 2019. dead.
  12. Web site: Evaluamos. TV Digital no ha llegado a toda Colombia y la CNTV ya piensa en modificar la norma. es. 21 July 2011.
  13. Web site: Panama adopts DVB-T. DVB.org. 19 May 2009. 26 June 2016. https://web.archive.org/web/20130903055251/http://dvb.org/news_events/news/panama-adopts-dvb-t/index.xml. 3 September 2013. dead.
  14. Web site: KTV Ltd.. 26 June 2016.
  15. Web site: Plan for the introduction of terrestrial digital television broadcasting (DVB-T) in the Republic of Bulgaria. . bg. 2012-12-17.
  16. Web site: Digital Television. NURTS (TV tower operator). 2012-12-17. https://web.archive.org/web/20121201000256/http://nurts.bg/en/uslugi/%D1%86%D0%B8%D1%84%D1%80%D0%BE%D0%B2%D0%B0-%D0%B5%D1%84%D0%B8%D1%80%D0%BD%D0%B0-%D1%82%D0%B5%D0%BB%D0%B5%D0%B2%D0%B8%D0%B7%D0%B8%D1%8F-dvb-t/. 1 December 2012. dead.
  17. Web site: Digital Ísland. fjarskiptahandbokin.is. is. 2009-10-27. https://web.archive.org/web/20090831020837/http://www.fjarskiptahandbokin.is/index.php?option=com_content&task=view&id=75&Itemid=125. 31 August 2009. dead.
  18. Web site: Russia adopts DVB-T2. September 29, 2011. dmy-all. Advanced-Television.com.
  19. Web site: ETV: trial DVB-T2 network. sr. 2012-03-22. dead. https://web.archive.org/web/20120416011557/http://etv.rs/vesti/74-pilot-mreza. 16 April 2012. dmy-all.
  20. Web site: Switzerland to switch off DTT on June 3, 2019. 6 December 2018.
  21. Web site: TRT Kurumsal Profil - TRT Kurumsal .
  22. Web site: RTÜK | Sayısal Yayıncılık Nedir? .
  23. Web site: 100,000 likes – Oqaab reaches over 1 Mio TV Households. 31 March 2015. Oqaab.af. 26 June 2016. https://web.archive.org/web/20160323182055/http://www.oqaab.af/first-digital-terrestrial-television-network-dvb-t2-starts-broadcasting/. 23 March 2016. dead.
  24. Web site: Samart eyes Middle East market for digital TV-enabled smartphone. Rapid TV News. 19 May 2014. 26 June 2016. Rebecca. Hawkes.
  25. Web site: Digital TV services to be introduced in Bangladesh by 2014. Asia-Pacific Broadcasting Union. 5 June 2012.
  26. Web site: PERSYARATAN TEKNIS ALAT DAN PERANGKAT PENERIMA TELEVISI SIARAN DIGITAL BERBASIS STANDAR DIGITAL VIDEO BROADCASTING TERRESTRIAL – SECOND GENERATION. KomInfo.go.id. Ministry of Communication and Information Technology (Indonesia). 1 April 2017. https://web.archive.org/web/20140331090643/https://web.kominfo.go.id/sites/default/files/Lampiran%20RPM%20Persyaratan%20Teknis%20Alat%20dan%20Perangkat%20Penerima%20Televisi%20Siaran%20Digital%20Berbasis%20Standard%20Digital%20Video%20Broadcasting%20Teresterial%20-%20Second%20Generation%20.pdf. 31 March 2014. live.
  27. Web site: Standar Penyiaran Televisi Digital. KomInfo.go.id. Ministry of Communication and Information Technology (Indonesia). 19 February 2012. https://web.archive.org/web/20170627030533/https://web.kominfo.go.id/sites/default/files/Permen%2037%20Standar%20Penyiaran%20TV%20Digital.pdf. 27 June 2017. dead.
  28. Web site: Kuwait TV opts for Harris DVB-T2 technology . Hawkes . Rebecca. 26 February 2014 . Rapid TV News . 2014-04-11.
  29. Web site: Kyrgyztelecom launches DVB-T2 & DVB-S2 . DVB.org . 7 November 2014 . 7 April 2016 . https://web.archive.org/web/20160419082538/https://www.dvb.org/news/kyrgyztelecom-launches-dvb_t2--dvb_s2/country/kyrgyzstan . 19 April 2016 . dead .
  30. Web site: 北朝鮮で4局が地上デジタル放送を実施中、ASUS ZenFone Go TVで確認 . ja . blogofmobile.com . 8 September 2019 . 24 June 2020.
  31. Web site: Report: DPRK testing digital TV. Martyn. Williams. 17 March 2013. North Korea Tech – 노스코리아테크. 25 September 2019. https://web.archive.org/web/20190923145947/http://www.northkoreatech.org/2013/03/17/report-dprk-testing-digital-tv/. 23 September 2019. live.
  32. Web site: Qatar Goes DVB-T2 . . 11 December 2013 . DVB.org . 12 April 2014 . https://web.archive.org/web/20190926000455/https://www.dvb.org/news/qatar-goes-dvb_t2 . 26 September 2019 . dead .
  33. Web site: Tajikistan Confirms DVB-T2 Adoption . DVB.org . 4 February 2014 . 7 April 2016 . https://web.archive.org/web/20161229103720/https://www.dvb.org/news/tajikistan-confirms-dvb_t2-adoption/country/tajikistan . 29 December 2016 . dead .
  34. Web site: BusinessDay – State U-turn on Nyanda's digital-TV signal plan. Mochiko. Thabiso. BusinessDay.co.za. BDFM Publishers. 26 November 2010. 26 November 2010. live. https://web.archive.org/web/20101130121634/http://www.businessday.co.za/articles/Content.aspx?id=127899. 30 November 2010. dmy-all.
  35. Web site: DVB-T2 chosen as digital TV standard . James . Etherington-Smith . 3 January 2011 . MyBroadband.co.za . 2011-01-03 . dmy-all.