Digital television in the United States
Encyclopedia
In the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

, digital television
Digital television
Digital television is the transmission of audio and video by digital signals, in contrast to the analog signals used by analog TV...

 broadcasts, or DTV, can be received via cable
Cable television
Cable television is a system of providing television programs to consumers via radio frequency signals transmitted to televisions through coaxial cables or digital light pulses through fixed optical fibers located on the subscriber's property, much like the over-the-air method used in traditional...

, via internet
Internet television
Internet television is the digital distribution of television content via the Internet...

, via satellite
Satellite television
Satellite television is television programming delivered by the means of communications satellite and received by an outdoor antenna, usually a parabolic mirror generally referred to as a satellite dish, and as far as household usage is concerned, a satellite receiver either in the form of an...

, or via free over-the-air
Terrestrial television
Terrestrial television is a mode of television broadcasting which does not involve satellite transmission or cables — typically using radio waves through transmitting and receiving antennas or television antenna aerials...

 (OTA) digital terrestrial television
Digital terrestrial television
Digital terrestrial television is the technological evolution of broadcast television and advance from analog television, which broadcasts land-based signals...

 - much like analog television broadcasts have been. Full-power analog television broadcasts, however, were required by U.S. federal law to cease by June 12, 2009. Low-power
Low-power broadcasting
Low-power broadcasting is electronic broadcasting at very low power and low cost, to a small community area.The terms "low-power broadcasting" and "micropower broadcasting" should not be used interchangeably, because the markets are not the same...

, Class A
Class A television service
The class A television service is a system for regulating some low-power television stations in the United States. Class A stations are denoted by the broadcast callsign suffix "-CA" or "-CD" , although very many analog -CA stations have a digital companion channel that was assigned the -LD...

, and TV Translator stations are not currently required to cease analog broadcasts. Also by law, digital broadcasts - when transmitted as OTA signals - must conform to ATSC standards.; it is unclear whether satellite operators are free to use their own proprietary standards; and many standards exist for internet television (most are proprietary).

Standards

The U.S. opted to adhere to ATSC standards for broadcast digital television. These standards define, among other things, format and transmission criteria that ensure consistency, accessibility, and fairness for consumers and equipment manufacturers alike in the U.S., as well as international compatibility.

Format standards

The five main ATSC formats of DTV currently broadcast in the U.S. are:
  • Standard definition
    Standard-definition television
    Sorete-definition television is a television system that uses a resolution that is not considered to be either enhanced-definition television or high-definition television . The term is usually used in reference to digital television, in particular when broadcasting at the same resolution as...

    —480i, to maintain compatibility with existing NTSC
    NTSC
    NTSC, named for the National Television System Committee, is the analog television system that is used in most of North America, most of South America , Burma, South Korea, Taiwan, Japan, the Philippines, and some Pacific island nations and territories .Most countries using the NTSC standard, as...

     sets when a digital television broadcast is converted back to an analog one—either by a converter box
    Coupon-eligible converter box
    A coupon-eligible converter box was a digital television adapter that met eligibility specifications for subsidy "coupons" from the United States government...

     or a cable/satellite operator's proprietary equipment
    Cable converter box
    A cable converter box or television converter box is an electronic tuning device that transposes/converts any of the available channels from a cable television service to an analog RF signal on a single channel, usually VHF channel 3 or 4. The device allows a television set that is not “cable...

  • Enhanced definition
    Enhanced-definition television
    Enhanced-definition television, or extended-definition television, is a United States Consumer Electronics Association marketing shorthand term for certain digital television formats and devices...

    —480p, about the same quality as current DVDs
  • High definition
    High-definition television
    High-definition television is video that has resolution substantially higher than that of traditional television systems . HDTV has one or two million pixels per frame, roughly five times that of SD...

    —720p
  • High definition
    High-definition television
    High-definition television is video that has resolution substantially higher than that of traditional television systems . HDTV has one or two million pixels per frame, roughly five times that of SD...

    —1080i
  • High definition
    High-definition television
    High-definition television is video that has resolution substantially higher than that of traditional television systems . HDTV has one or two million pixels per frame, roughly five times that of SD...

    —1080p (only used by a few cable operators, currently no terrestrial stations broadcast in 1080p)


Most digital television sets sold in the U.S. use a display with a 16:9 aspect ratio
Aspect ratio (image)
The aspect ratio of an image is the ratio of the width of the image to its height, expressed as two numbers separated by a colon. That is, for an x:y aspect ratio, no matter how big or small the image is, if the width is divided into x units of equal length and the height is measured using this...

 to optimally display HDTV-formatted content. Lower-resolution sources like regular DVDs may be upscaled to the native resolution of the TV. Most television broadcasts, as of 2007, were in standard definition.

In North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

, FOX
Fox Broadcasting Company
Fox Broadcasting Company, commonly referred to as Fox Network or simply Fox , is an American commercial broadcasting television network owned by Fox Entertainment Group, part of Rupert Murdoch's News Corporation. Launched on October 9, 1986, Fox was the highest-rated broadcast network in the...

, MyNetworkTV
MyNetworkTV
MyNetworkTV is a television broadcast syndication service in the United States, owned by the Fox Entertainment Group, a division of News Corporation...

 (both owned by the News Corporation
News Corporation
News Corporation or News Corp. is an American multinational media conglomerate. It is the world's second-largest media conglomerate as of 2011 in terms of revenue, and the world's third largest in entertainment as of 2009, although the BBC remains the world's largest broadcaster...

), ABC
American Broadcasting Company
The American Broadcasting Company is an American commercial broadcasting television network. Created in 1943 from the former NBC Blue radio network, ABC is owned by The Walt Disney Company and is part of Disney-ABC Television Group. Its first broadcast on television was in 1948...

, and ESPN
ESPN
Entertainment and Sports Programming Network, commonly known as ESPN, is an American global cable television network focusing on sports-related programming including live and pre-taped event telecasts, sports talk shows, and other original programming....

 (ABC and ESPN are both owned by Disney
The Walt Disney Company
The Walt Disney Company is the largest media conglomerate in the world in terms of revenue. Founded on October 16, 1923, by Walt and Roy Disney as the Disney Brothers Cartoon Studio, Walt Disney Productions established itself as a leader in the American animation industry before diversifying into...

) currently broadcast 720p content. NBC
NBC
The National Broadcasting Company is an American commercial broadcasting television network and former radio network headquartered in the GE Building in New York City's Rockefeller Center with additional major offices near Los Angeles and in Chicago...

, Universal HD
Universal HD
Universal HD is an HDTV cable television network owned by NBCUniversal. The channel was known as Bravo HD+ until December 1, 2004. The network exclusively broadcasts in high definition 1080i...

 (both owned by the NBC Universal
NBC Universal
NBCUniversal Media, LLC is a media and entertainment company engaged in the production and marketing of entertainment, news, and information products and services to a global customer base...

 subsidiary of General Electric
General Electric
General Electric Company , or GE, is an American multinational conglomerate corporation incorporated in Schenectady, New York and headquartered in Fairfield, Connecticut, United States...

 and Vivendi
Vivendi
Vivendi SA is a French international media conglomerate with activities in music, television and film, publishing, telecommunications, the Internet, and video games. It is headquartered in Paris.- History :...

), CBS
CBS
CBS Broadcasting Inc. is a major US commercial broadcasting television network, which started as a radio network. The name is derived from the initials of the network's former name, Columbia Broadcasting System. The network is sometimes referred to as the "Eye Network" in reference to the shape of...

, The CW (co-owned by CBS
CBS Corporation
CBS Corporation is an American media conglomerate focused on commercial broadcasting, publishing, billboards and television production, with most of its operations in the United States. The President and CEO of the company is Leslie Moonves. Sumner Redstone, owner of National Amusements, is CBS's...

 and Time Warner
Time Warner
Time Warner is one of the world's largest media companies, headquartered in the Time Warner Center in New York City. Formerly two separate companies, Warner Communications, Inc...

), HBO (owned by Time Warner), Showtime (owned by CBS), Starz!
Starz!
Starz is an American premium subscription channel that features mainly first-run motion pictures, along with some original programming...

 (owned by Liberty Media
Liberty Media
Liberty Media Corporation is an American media conglomerate and the control is exercised by company Chairman John C. Malone, who owns a majority of the voting shares....

), HDNet
HDNet
HDNet is a men's interest television channel in the United States, broadcasting exclusively in high-definition format and available via cable and satellite television...

, MTV2
MTV2
MTV2 is a cable network that is widely available in the United States on digital cable and satellite television, and is progressively being added to analogue cable lineups across the nation...

 (owned by Viacom
Viacom
Viacom Inc. , short for "Video & Audio Communications", is an American media conglomerate with interests primarily in, but not limited to, cinema and cable television...

), TNT
Turner Network Television
Turner Network Television is an American cable television channel created by media mogul Ted Turner and currently owned by the Turner Broadcasting System division of Time Warner...

 (owned by Time Warner), CNN
CNN
Cable News Network is a U.S. cable news channel founded in 1980 by Ted Turner. Upon its launch, CNN was the first channel to provide 24-hour television news coverage, and the first all-news television channel in the United States...

 (also owned by Time Warner), Discovery HD Theater
Discovery HD Theater
Velocity is an American high-definition, commercial-based, cable- and satellite-television channel owned by Discovery Communications...

(owned by Discovery Communications
Discovery Communications
Discovery Communications, Inc. is an American global media and entertainment company. The company started as a single channel in 1985, The Discovery Channel. Today, DCI has global operations offering 28 network entertainment brands on more than 100 channels in more than 180 countries in 39...

) and the Public Broadcasting Service
Public Broadcasting Service
The Public Broadcasting Service is an American non-profit public broadcasting television network with 354 member TV stations in the United States which hold collective ownership. Its headquarters is in Arlington, Virginia....

 currently broadcast 1080i content. In Canada, virtually all over-the-air HD stations broadcast 1080i, as do most cable specialty channels. For list of local over the air HD channels visit a web site like antennaweb.org

Cable and satellite

Currently, most Americans get digital television broadcasts via cable or satellite. Digital cable television systems with an activated channel capacity of 750 MHz or greater, are required by the FCC to follow ANSI/SCTE transmission standards with the exception of cable systems that only pass through 8 VSB modulated signals. Digital television sets (equipped with ATSC tuners) are often capable of viewing a baseline set of unencrypted digital programming, known as basic cable, which typically include local network television affiliates. According to FCC
Federal Communications Commission
The Federal Communications Commission is an independent agency of the United States government, created, Congressional statute , and with the majority of its commissioners appointed by the current President. The FCC works towards six goals in the areas of broadband, competition, the spectrum, the...

 regulations, the remaining encrypted channels must be viewable with a receiver equipped with a CableCARD
CableCARD
CableCARD is a special-use PCMCIA card that allows consumers in the United States to view and record digital cable television channels on digital video recorders, personal computers and television sets without the use of other equipment such as a set top box provided by a cable television company...

,.

Terrestrial

Digital television transmissions over-the-air (OTA) are now available in most metropolitan areas in the U.S., often carrying both standard-definition and high-definition (HDTV) transmissions of the same stations. In fact, by the analog shut-off date of June 12, 2009, all Full Power OTA stations in the U.S. will, by law, have to either transmit their broadcasts digitally, or shut down.

Many stations have already used the switch to digital transmission as an opportunity to transition from 480i broadcasts to digital HD OTA broadcasts (either in 720p or 1080i), though this change is voluntary.

Within a distance of 35 to 40 miles from the broadcast stations, it is possible that no equipment more special than perhaps a simple antenna (such as "rabbit ears") may be necessary to receive a DTV broadcast signal OTA—at least some of the time for some of the channels. Any television equipped with an ATSC tuner may display DTV broadcasts properly. Some customers are already discovering that terrain, trees, rain, snow, wind, and even the movement of people around the room interfere with reception to one degree of another, from signals breaking up to total loss of signal. (Few ATSC-equipped televisions or converter boxes have internal antennas, in contrast to analog sets available in years past).

Transition from analog to digital OTA broadcasts in 2009

It is estimated that as of April 2007, 28% of American households had an HDTV set, a total of 35 million sets, and that 86% of owners were highly satisfied with the HDTV programming Some extimate that by the end of 2010, 59% of American TVs will be HDTVs. All TV stations currently broadcast in both digital and analog and major networks broadcast in HD in most markets.

While many in the industry wanted a flexible or delayed deadline, the FCC forced the issue at the behest of Congress. Congress wanted to reclaim the spectrum for emergency services. They also wanted to auction
Auction
An auction is a process of buying and selling goods or services by offering them up for bid, taking bids, and then selling the item to the highest bidder...

 off the 76-88 MHz frequencies and old analog channels 60 to 69, and channels 52 to 59 by mandating DTV tuner
Tuner
Tuner may refer to someone or something which adjusts or configures a mechanical, electronic, or musical device.- Electronic :* Antenna tuner, a device to adjust the resonance frequency of an antenna or transmission line...

s be phased in to all new TV sets, beginning with the largest. Many dates were proposed, but Congress finally fixed February 17, 2009 (later extending it until June 12, 2009), in law as the maximum end date for analog television authorizations. Because this date comes after the NCAA
National Collegiate Athletic Association
The National Collegiate Athletic Association is a semi-voluntary association of 1,281 institutions, conferences, organizations and individuals that organizes the athletic programs of many colleges and universities in the United States...

's Bowl Championship Series
Bowl Championship Series
The Bowl Championship Series is a selection system that creates five bowl match-ups involving ten of the top ranked teams in the NCAA Division I Football Bowl Subdivision , including an opportunity for the top two to compete in the BCS National Championship Game.The BCS relies on a combination of...

 and the NFL
National Football League
The National Football League is the highest level of professional American football in the United States, and is considered the top professional American football league in the world. It was formed by eleven teams in 1920 as the American Professional Football Association, with the league changing...

's Super Bowl XLIII
Super Bowl XLIII
Super Bowl XLIII was an American football game pitting the American Football Conference champion Pittsburgh Steelers against the National Football Conference champion Arizona Cardinals to decide the National Football League champion for the 2008 season. The game was played on February 1, 2009,...

, there will be less of a chance of an acute hardware shortage from people waiting until the last minute to purchase an ATSC tuner
ATSC tuner
An ATSC tuner, often called an ATSC receiver or HDTV tuner is a type of television tuner that allows reception of digital television television channels transmitted by television stations in North America, parts of Central America and South Korea that use ATSC standards...

 than there would have been with a January 1 cutoff. The original deadline of January 1, 2006 was abolished when it was realized that TV stations and customers would not be able to meet the earlier deadline.

Early rollout of transition

On May 8, 2008, FCC Chairman Kevin J. Martin announced the agency would test run the transition to digital television in Wilmington, North Carolina
Wilmington, North Carolina
Wilmington is a port city in and is the county seat of New Hanover County, North Carolina, United States. The population is 106,476 according to the 2010 Census, making it the eighth most populous city in the state of North Carolina...

, beginning September 8, 2008. This test run was to work out problems that might have occurred before the complete transition.

See also

  • Digital television transition
    Digital television transition
    The digital television transition is the process in which analog television broadcasting is converted to and replaced by digital television. This primarily involves both TV stations and over-the-air viewers; however it also involves content providers like TV networks, and cable television...

  • High-definition television in the United States
    High-definition television in the United States
    High-definition television in the United States was introduced in 1998 and has since become increasingly popular. Dozens of HD channels are available in millions of homes and businesses both terrestrially and via subscription services such as satellite, cable and IPTV...

  • CECB - Coupon-Eligible Converter Box

External links

  • "The Digital TV Transition: What You Need to Know About DTV" (FCC
    Federal Communications Commission
    The Federal Communications Commission is an independent agency of the United States government, created, Congressional statute , and with the majority of its commissioners appointed by the current President. The FCC works towards six goals in the areas of broadband, competition, the spectrum, the...

    )
  • DTV Transition (DTV Transition Coalition)
  • AntennaWeb (local availability of OTA DTV broadcasts, including HD)
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