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. In June 2011, Nielsen Media Research reported that 75.5 million American homes (two-thirds of all homes) contain at least one HDTV.[1]
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[edit] High definition versus standard or enhanced definition
It is not clear whether broadcasting HDTV or multiple standard definition (SD) channels during non-primetime hours will become common. Many Public Broadcasting Service member stations are now carrying SD multicasts when not broadcasting in HDTV; but unlike many commercial stations, most of these multicasts are suspended while HDTV programs are being broadcast.
The prevailing expectation is that native HDTV (i.e., programming recorded with a digital HDTV camera) during primetime will predominate. The great majority of primetime television shows in the United States are available in HDTV at the network level. It is up to the affiliates, not all of which have HDTV broadcast capability, to retransmit these shows at HDTV resolutions. A number of non-primetime shows, including morning news shows and some soap operas, are also available in HDTV.
One of the major problems in complete replacement of SD TV by HD is an absence of broadcast channels for HD signals transmission. Currently, the "simulated HD" broadcast varies near 2 GB per hour (including sound), which is lower than the information rate used for an SD signal in "old DVD" recording. At such low rate a single high-quality frame (24-bit color 2 M pixel) would arrive in 10 s. As a result of the extreme compression (with rates of 300 from a complete HD signal at >600 GB/h), only very static frames can look sharper than in SD programming, while many dynamic frames, with a low level of motion, might be "sacrificed" and can be even worse than they would be in SD transmission, which could use a smaller fraction of the same throughput for static frames.
[edit] From proposals to introduction
The Federal Communications Commission (FCC) began soliciting proposals for a new television standard for the U.S. in the late 1980s and later decided to ask companies competing to create the standard to pool their resources and work together, forming what was known as the Grand Alliance in 1993.
On July 23, 1996, WRAL-TV (the CBS affiliate in Raleigh, North Carolina) became the first television station in the United States to broadcast a digital television signal.[2]
HDTV sets became available in the U.S. in 1998 and broadcasts began around November 1998. The first public HDTV broadcast was of the launch of the space shuttle Discovery and John Glenn's return to space; that broadcast was made possible in part by Harris Corporation.[3] The first commercial broadcast of a local sporting event in HD was during Major League Baseball's Opening Day on March 31, 1998, the Texas Rangers against the Chicago White Sox from The Ballpark in Arlington in Arlington, TX. The telecast was produced by LIN productions and broadcasted locally on Fort Worth, Texas NBC affiliate KXAS channel 5. This telecast was also the first commercial HD broadcast in the state of Texas.[4] The first major sporting event broadcast nation wide in HD was Super Bowl XXXIV on January 30, 2000.
[edit] Satellite and cable
Satellite television companies in the United States, such as Dish Network and DirecTV, started to carry HD programming in 2002. Satellite transmissions in the U.S. use various forms of PSK modulation. A separate tuner is required to receive HD satellite broadcasts.
Cable television companies in the U.S. generally prefer to use 256-QAM to transmit HDTV. Many of the newer HDTVs with integrated digital tuners include support for decoding 256-QAM in addition to 8VSB for OTA digital. Some cable television companies, such as Comcast, started carrying HDTV in 2003. Currently, HD programming is carried by all major television networks in most DMAs, including ABC, CBS, NBC, FOX, PBS, The CW, MyNetworkTV and Telemundo; and on some independent stations.
[edit] List of current high-definition channels
[edit] Broadcast Networks |
[edit] Spanish broadcast networks
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[edit] HD only networks
[edit] News and information networks
- BBC America HD
- BBC World News HD
- Bloomberg Television HD
- CNBC HD
- CNN HD
- C-SPAN HD
- C-SPAN 2 HD
- C-SPAN 3 HD
- Fox Business Network HD
- Fox News Channel HD
- HLN HD
- msnbc HD
- TV Guide Network HD
- The Weather Channel HD
[edit] Sports networks[edit] National sports networks
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[edit] Regional sports networks
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[edit] Religious[edit] Premium services
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[edit] Defunct
[edit] Scheduled HD channel launches
- Disney Junior HD - Will replace SOAPnet, which does not have an HD feed, on march 23, 2012
- Pac-12 Network HD - August 2012
- TVG Network HD - TBA
- Universal Sports Network HD - to launch sometime in 2012.
- WWE Network HD - Fall 2012
[edit] See also
[edit] References
- ^ Nielsen: Two Thirds of All TV Homes Now Have An HD Set Multichannel News June 15, 2011
- ^ History of WRAL Digital
- ^ "HDTV: Launched and Counting.". Broadcasting and Cable (BNET). 1998-11-02. http://findarticles.com/p/articles/mi_hb5053/is_199811/ai_n18386452?tag=content;col1. Retrieved 2008-10-24.[dead link]
- ^ KXAS Texas Rangers vs Chicago White Sox introduction - March 31, 1998
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