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{{Short description|
{{Redirect|ATSC}}
{{Use mdy dates|date=January 2016}}
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{{Table Digital video broadcast standards}}
'''Advanced Television Systems Committee''' ('''ATSC''') '''standards''' are an
The ATSC standards were developed in the early 1990s by the [[Grand Alliance (HDTV)|Grand Alliance]], a consortium of electronics and telecommunications companies that assembled to develop a specification for what is now known as [[HDTV]]. The standard is now administered by the [[Advanced Television Systems Committee]]. It includes a number of [[patent]]ed elements, and licensing is required for devices that use these parts of the standard. Key among these is the [[8VSB]] modulation system used for [[Terrestrial television|over-the-air]] broadcasts.
ATSC includes two primary high definition video formats, [[1080i]] and [[720p]]. It also includes [[SDTV|standard-definition]] formats, although initially only HDTV services were launched in the digital format. ATSC can carry multiple channels of information on a single stream, and it is common for there to be a single high-definition signal and several standard-definition signals carried on a single 6 MHz (former NTSC) channel allocation.
== Background ==
{{update|section|date=July 2022}}
The high-definition television standards defined by the ATSC produce [[widescreen]] [[16:9]] images up to 1920×1080 [[pixel]]s in size{{snd}}more than six times the [[display resolution]] of the earlier standard. However, many different image sizes are also supported. The reduced bandwidth requirements of lower-resolution images allow up to six [[SDTV|standard-definition]] "subchannels" to be broadcast on a single 6 [[MegaHertz|MHz]] [[TV channel]].
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ATSC supports 5.1-channel [[surround sound]] using [[Dolby Digital]]'s [[Dolby AC-3|AC-3]] format. Numerous auxiliary [[datacasting]] services can also be provided.
Many aspects of ATSC
As with other systems, ATSC depends on numerous interwoven standards, e.g., the [[EIA-708]] standard for digital [[closed captioning]], leading to variations in implementation.
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== Digital switchover ==
{{See also|Digital television transition in the United States|Digital television in Canada|Television in Mexico}}
ATSC [[DTV transition in the United States|replaced]] much of the [[analog television|analog]] [[NTSC]] television system<ref>{{cite
Broadcasters who used ATSC and wanted to retain an analog signal were temporarily forced to broadcast on two separate channels, as the ATSC system requires the use of an entire separate channel. Channel numbers in ATSC do not correspond to RF frequency ranges, as they did with [[analog television]]. Instead, [[virtual channel]]s, sent as part of the metadata along with the program(s), allow channel numbers to be remapped from their physical [[Radio frequency|RF]] channel to any other number 1 to 99, so that ATSC stations can either be associated with the related NTSC channel numbers, or all stations on a network can use the same number. There is also a standard for [[distributed transmission system]]s (DTx), a form of [[single-frequency network]] which allows for the synchronised operation of multiple on-channel [[relay transmitter|booster stations]].
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Currently, the [[Federal Communications Commission]] requires cable operators in the United States to carry the analog or digital transmission of a terrestrial broadcaster (but not both), when so requested by the broadcaster (the "[[must-carry]] rule"). The [[Canadian Radio-television and Telecommunications Commission]] in Canada does not have similar rules in force with respect to carrying ATSC signals.
However, cable operators have still been slow to add ATSC channels to their lineups for legal, regulatory, and plant & equipment related reasons. One key technical and regulatory issue is the modulation scheme used on the cable: cable operators in the U.S. (and to a lesser extent Canada) can determine their own method of modulation for their plants. Multiple standards bodies exist in the industry: the [[SCTE]] defined [[256-QAM]] as a modulation scheme for cable in a cable industry standard, [http://www.scte.org/documents/pdf/Standards/ANSISCTE072006.pdf ANSI/SCTE 07 2006: Digital Transmission Standard For Cable Television] {{Webarchive|url=https://web.archive.org/web/20100705154402/http://www.scte.org/documents/pdf/Standards/ANSISCTE072006.pdf |date=July 5, 2010 }}. Consequently, most U.S. and Canadian cable operators seeking additional capacity on the cable system have moved to [[256-QAM]] from the [[64-QAM]] modulation used in their plant, in preference to the [[16VSB]] standard originally proposed by ATSC. Over time [[256-QAM]] is expected to be included in the ATSC standard.
There is also a standard for transmitting ATSC via satellite; however, this is only used by [[TV network]]s{{Citation needed|date=June 2010}}. Very few [[Earth station|teleports]] outside the U.S. support the ATSC satellite transmission standard, but teleport support for the standard is improving. The ATSC satellite transmission system is not used for [[direct-broadcast satellite]] systems; in the U.S. and Canada these have long used either [[DVB-S]] (in standard or modified form) or a proprietary system such as [[Digital Satellite Service|DSS]] or [[DigiCipher 2]].
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{{Main|ATSC-M/H}}
Mobile reception of digital stations using ATSC has, until 2008, been difficult to impossible, especially when moving at vehicular speeds. To overcome this, there are several proposed systems that report improved mobile reception: [[Samsung]]/[[Rhode & Schwarz]]'s [[A-VSB]], [[Harris Broadcast|Harris]]/[[LG]]'s
Mobile reception of some stations will still be more difficult, because 18 UHF channels in the U.S. have been removed from TV service, forcing some broadcasters to stay on VHF. This band requires [[Television antenna|larger antennas]] for reception, and is more prone to [[electromagnetic interference]] from [[engine]]s and rapidly changing [[Multipath propagation|multipath]] conditions.{{Citation needed|date=January 2008}}
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On March 28, 2016, the Bootstrap component of ATSC 3.0 (System Discovery and Signalling) was upgraded from candidate standard to finalized standard.<ref>{{cite web|url=http://www.tvtechnology.com/news/0002/first-element-of-atsc-30-approved-for-standard/278263|title=First Element of ATSC 3.0 Approved for Standard|website=tvtechnology.com|date=March 28, 2016|access-date=March 16, 2018|url-status=live|archive-url=https://web.archive.org/web/20170302205029/http://www.tvtechnology.com/news/0002/first-element-of-atsc-30-approved-for-standard/278263|archive-date=March 2, 2017|df=mdy-all}}</ref>
On June 29, 2016, [[NBC]] affiliate [[WRAL-TV]] in [[Raleigh, North Carolina]], a station known for its pioneering roles in testing the original DTV standards, launched an experimental ATSC 3.0 channel carrying the station's programming in 1080p, as well as a 4K demo loop.<ref name="tvnc-atsc3">{{cite web|title=WRAL Launches ATSC 3.0 Service|url=http://www.tvnewscheck.com/article/95854/first-again-wral-launches-atsc-30-service|website=TVNewsCheck|access-date=
<!-- Deleted image removed: [[File:
;Structure/ATSC 3.0 System Layers<ref>{{cite web |url=http://www.tvtechnology.com/portals/0/ATSC30Layers.png |title=Overview - ASTC 3.0 System Layers |format=PNG |access-date=2016-05-18 |url-status=dead |archive-url=https://web.archive.org/web/20161004185359/http://www.tvtechnology.com/portals/0/ATSC30Layers.png |archive-date=October 4, 2016 |df=mdy-all }}</ref>
# Bootstrap: System Discovery and Signalling
# Physical Layer: Transmission ([[OFDM]])
# Protocols: [[Internet Protocol|IP]], [[MPEG media transport|MMT]]
# Presentation: Audio and Video standards (to be determined), [[Ultra HD]] with [[High-definition video|High Definition]] and [[standard
# Applications: Screen is a web page
==== ATSC 3.0 advantages ====
# Better image quality. ATSC 3.0 allows [[
# Reception upgrades. ATSC 3.0 allows the same [[Television antenna|aerial]] to receive more channels with better quality.
# Portable devices such as mobile phones, tablets, and car
#
# Audience measure.
# [[Targeted advertising]] with the assistance of local network [[Wi-Fi]].
# Content variety and diversification.
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*{{flagcountry|Jamaica}} Will convert to ATSC 3.0 instead of 1.0. The conversion will begin in 2022 and is expected to be completed by 2023.<ref>{{cite news |title=Digital Television Switchover in Jamaica set to begin in 2022 |url=https://jamaica-gleaner.com/article/news/20211207/digital-television-switchover-jamaica-set-begin-2022 |work=[[The Gleaner]] |publisher=[[Gleaner Company]] |date=December 7, 2021 |access-date=January 8, 2021 }}</ref>
*{{flagcountry|Mexico}} [[Television in Mexico|began converting]] to ATSC in 2013;<ref name=Dibble_2013>{{cite news|last=Dibble|first=Sandra|title=New turn for Tijuana's transition to digital broadcasting|url=http://www.utsandiego.com/news/2013/may/30/new-turn-for-tijuanas-transition-to-digital-broac/|access-date=June 4, 2013|newspaper=San Diego Union-Tribune|date=May 30, 2013|url-status=live|archive-url=https://web.archive.org/web/20130906225915/http://www.utsandiego.com/news/2013/may/30/new-turn-for-tijuanas-transition-to-digital-broac/|archive-date=September 6, 2013|df=mdy-all}}</ref> a full transition was scheduled for December 31, 2015,<ref name="dgm 1" /> but due to technical and economic issues for some transmitters, the full transition was extended to December 31, 2016.
*{{flagcountry|
*{{flagcountry|Trinidad and Tobago}} will convert to ATSC 3.0 instead of ATSC 1.0. The conversion process will begin in March 2023 and is expected to be completed by 2026.<ref name="TT ATSC 3.0">{{cite web |title=Notice |url=https://tatt.org.tt/Home/Announcements4/ReadMore/tabid/350/ArticleId/677/Notice-22.aspx |website=Telecommunications Authority of Trinidad and Tobago |access-date=2022-01-26}}</ref>
*{{flagcountry|United States}} Full-power television stations in the [[Digital television in the United States|United States]] ended analog television service on June 12, 2009. Analog [[Low-power broadcasting|low-power]] stations and translators were all wound down by July 13, 2021.<ref name="US LPTV trans">{{citation |url=http://www.fcc.gov/guides/low-power-television-lptv-service |title=Low Power Television (LPTV) Service |work=CDBS Database |date=May 17, 2011 |publisher=[[Federal Communications Commission]] |access-date=April 3, 2013 |url-status=live |archive-url=https://web.archive.org/web/20130401214127/http://www.fcc.gov/guides/low-power-television-lptv-service |archive-date=April 1, 2013 |df=mdy-all }}</ref><ref>[https://apps.fcc.gov/edocs_public/attachmatch/DA-17-442A1.pdf FCC Public Notice: "THE INCENTIVE AUCTION TASK FORCE AND MEDIA BUREAU ANNOUNCE PROCEDURES FOR LOW POWER TELEVISION, TELEVISION TRANSLATOR AND REPLACEMENT TRANSLATOR STATIONS DURING THE POST-INCENTIVE AUCTION TRANSITION", May 17, 2017]</ref>
=== South America ===
*{{flagcountry|Guyana}}
*{{flagcountry|Suriname}} Suriname
=== Asia/Pacific ===
*{{flagcountry|South Korea}} South Korea completed its transition to ATSC on December 31, 2012, although it still operates some analog signals along its northern border for reception in [[North Korea]].<ref name=Yonhap_2013>{{cite news|title=N. Korea in the process of introducing digital TV broadcasting|url=http://english.yonhapnews.co.kr/northkorea/2013/03/19/2/0401000000AEN20130319005400315F.HTML|access-date=June 4, 2013|newspaper=Yonhap News Agency|date=March 19, 2013|url-status=live|archive-url=https://web.archive.org/web/20131001182546/http://english.yonhapnews.co.kr/northkorea/2013/03/19/2/0401000000AEN20130319005400315F.HTML|archive-date=October 1, 2013|df=mdy-all}}</ref><ref>{{cite web|title=North Korean television sets still receive South Korean signals|url=http://newfocusintl.com/north-korean-television-sets/|website=News Focus International|access-date=July 12, 2015|url-status=live|archive-url=https://web.archive.org/web/20150614041031/http://newfocusintl.com/north-korean-television-sets/|archive-date=June 14, 2015|df=mdy-all}}</ref>
*{{flagcountry|United States}} territories in the Pacific, including [[American Samoa]], [[Guam]], and the [[Northern Mariana Islands]] have adopted ATSC, as with the mainland.<ref name="US LPTV trans" />
== Countries and territories are available in using ATSC ==
*{{flagcountry|British Virgin Islands}}
*{{flagcountry|Saint Vincent and the Grenadines}}
== Patent holders ==
The following organizations hold [[patent]]s for the development of ATSC technology, as listed in the [[patent pool]] administered by [[MPEG LA]].
{| class="wikitable"
!Organizations<ref>{{cite web |title=Licensors Included in the ATSC Patent Portfolio License |url=https://www.mpegla.com/programs/atsc/licensors/ |website=[[MPEG LA]] |access-date=11 July 2019}}</ref>
!Active patents
!Expired patents (
!Total patents<ref name="mpegla">{{cite web |title=ATSC Patent List |url=https://www.mpegla.com/wp-content/uploads/atsc-att1.pdf |website=[[MPEG LA]] |access-date=
|-
|[[LG Electronics]]
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|354
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|[[Panasonic]]
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|50
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|[[Mitsubishi Electric]]
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|14
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|Vientos Alisios Co., Ltd.
|1▼
|0
▲|1
|1
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* [[Broadcast-safe]]
* [[Digital terrestrial television]] (DTT)
* [[DVB|Digital Video Broadcasting]] (DVB)
* [[CTA-708]]
* [[ISDB]] – Integrated Services Digital Broadcasting
*
* [[Standard-definition television]]
* [[T-DMB]] – South Korean terrestrial mobile digital broadcasting system
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== External links ==
*[https://www.atsc.org ATSC website]
*[https://www.expway.com/ ATSC-MH Platform for testing and deploying Mobile TV in the US]
*[https://web.archive.org/web/20170724043744/http://www.decontis.com/ ATSC Mobile DTV (ATSC-MH) Analysis, Monitoring, Measurement]
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{{DEFAULTSORT:Atsc}}
[[Category:ATSC standards| ]]
[[Category:MPEG]]
[[Category:Digital television]]
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