by Katherine M. (Miller) Kleinman
October 11, 2001
How it works.
Digital television's background.
Who is promoting digital television?
The problems it solves.
How digital television interconnects with other media.
Economic constraints.
Regulatory constraints.
Successful applications of digital television.
Unsuccessful applications of digital television.
Conclusion.
Bibliography.
Adopted by the Federal Communications Committee (FCC) in 1996, the new broadcasting system, to convert to analog broadcasts to digital television (DTV) will be the first change in American broadcasting in over fifty years. The new system has the potential to include high and standard definition television, datacasting, enhanced television, and multicasting. 1 As of April 2000, according to Bill McConnell of Broadcasting & Cable, 62% of U.S. households could receive digital signals. 2
Digital television works on the same principle as a computer, it uses binary code rather than a continuous, analog signal. 3 Digital video is coded using MPEG-2 video compression and AC-3 audio compression. It is then transported and transmitted using VSB-8 modulation to home receivers. 4
Standard definition television (SDTV) is a kind of digital television that is equal or superior to analog television. It may be broadcast in a 4:3 or 16:9 aspect ratio and may include Dolby digital audio. 5 The number of lines in a video signal is a measure of image quality. An average number of lines for SDTV are 480, which is the same as analog television. 6
High definition television (HDTV) presents the best picture and sound quality available through digital television. HDTV can be promoted as a unique service, since it is of higher quality than consumers are accustomed to. It contains twice as many lines as analog television and is broadcast in wide-screen, 16:9 a format. 7 HDTV formats include 1080 and 720 lines. 8
AC3 audio or 5.1 audio is the Dolby Digital audio standard selected for DTV.This system includes six audio channels (left, center, right, left rear, right rear, and subwoofer).Currently, only high-end HDTV programs will utilize Dolby digital audio. 9
Multicasting is an aspect of digital television that allows broadcasters to transmit multiple channels instead of just one. KAET's (Arizona State University's PBS station) webpage gives this definition of multicasting, "You can run a big, flashy, wide-load truck carrying an HDTV program and take up all the lanes, or you can send multiple compact cars down the same freeway, each carrying an SDTV program." 10
Without compression, digital television would not be possible. Video compression uses complicated mathematical equations to squeeze the large amount of information in the video signal into a smaller, manageable amount of information, without loss of quality. 11
The National Television Systems Committee (NTSC) system was developed in 1939 as the standard for television in the United States. NTSC is an analog system, which uses a range of voltages to represent an image. This is the system all current televisions in the United States operate on. 12
The first device to digitize a video signal was the digital time base corrector (TBC) in the mid 1970s. The digital TBC allowed broadcasters to use the new less-expensive videotape formats that were becoming commonly used. In the 1980s, digital video tape formats were developed that allowed multi-generation recording to be made with minimal quality loss. 13 The Japanese developed HDTV in the 1980s, but due to many economic and regulatory factors it did not become very widespread in usage. 14
In the 1990s there were many advances in digital signal processing and the compression schemes of MPEG-1 (Motion Pictures Experts Group) for low-quality video and MPEG-2 for broadcast quality video, were also created. 15
The new digital television standard created in 1996 was called ATSC video (advanced television systems committee). 16 The new system, also called the Grand Alliance digital system 17, required all television stations to broadcast only in digital by 2006. 18 Each station was given an additional 6 megahertz (MHz) channel of public spectrum to supplement its broadcast. 19 After 2006, the spectrum space once used by the broadcasters will be auctioned and redistributed by the FCC. 20
The FCC, the electronics manufacturers, and the broadcasters are promoting digital television. At the 2001 National Association of Broadcasters (NAB) convention, the NAB and the Consumer Electronics Association (CEA) announced that they would start working together to promote digital television to consumers starting in fall of 2001. Currently, consumers have no reason to buy a digital television set. Michael Grotticelli of Broadcasting and Cable states that, "If over-the-air distribution is going to be a factor in the future of DTV, it's going to take a Herculean effort to convince consumers that installing an antenna on their roof will bring them into the 21st century in television. Demand is crucial to DTV." 21
Digital television solves many problems: improves the quality of NTSC, gives broadcasters a chance to catch up to cable and satellite providers, with such services as datacasting and enhanced television, and it seems to give consumers more options. 22 One way in which it gives consumers more options is called an electronic programming guide (EPG). An EPG is used to select channels on a digital television. These guides can help the viewer navigate channels, much like digital satellites currently do. They can display programs by genre or category. They also let the television "learn" the viewing habits of the user. 23
Another resource possible for viewers could be enhanced television. Enhanced television or interactive television includes additional resources that viewers can download. The viewer can watch the television while downloading additional video, audio, text, and images related to the program. According to PBS's enhanced programming website,
"Enhanced TV represents the fusion of video, audio, images and text in an entirely new medium. Producers will be able to combine the storytelling power of video and film with enormous data channel of a digital television signal. Imagine your favorite PBS documentary accompanied by a companion CD-ROM, but with the content stored directly on your computer or in the memory of your digital set-top box." 24
Enhanced television allows the television to interconnect with other media. Currently models are being tested that send information directly to a computer hard-drive using the broadcasters spectrum or that use the telephone or cable modem to download information. In these ways digital television has the potential to interconnect with the Internet, video, audio, text, images, and other data. 25
A major economic problem for broadcaster is the cost of digital television, which is especially difficult for small stations. The average cost of conversion is $4 to $5 million per station. 26 Doug Standley, president of a Texas-based tower manufacture, says that stations building their own separate transmission facilities, is one of the reasons that the digital transition is happening so slowly. He believes, if broadcasters would share towers and use a 'co-location' approach, they could convert their station a lot easier. In a co-location approach, multiple stations share a common tower and transmission building. Standley states, "I feel that this transition will be successful only if broadcasters quit trying to work independently…More than 780 towers will have to be built to get almost every station on the air [with digital]. Nineteen of them were built in the year 2000. You do the math." 27
How do broadcasters recoup the $4 to $5 million per station necessary to convert to digital? 28 Many believe the answer is datacasting, which allows broadcasters to use leftover bandwidth to transmit data. 29 This data could include transcripts, web links, video, audio, text, or other graphics. 30 Broadcasters could set aside a few Mb/s of digital spectrum for delivery of data and then charge for the access to those bits. 31 Computers, set-top boxes, or other receivers could then decode information. DTV's broadband channel would allow this information to be downloaded about 600 times faster than a personal computer modem. 32
Another economic restraint is the cost of the television sets. Digital television sets are currently too expensive for the average or even above average family to afford. The most advanced sets now sell for $6,000 or more. 33 Two reasons for the delay in affordable digital sets have been caused by copy protection safeguards for protection of Hollywood's high-definition copyrighted movies 34 and the 18 different display formats currently approved for use. 35 Consumer advocacy groups and the CEA have protested about including receivers in television sets, because they believe that the receivers will increases prices. 36 Of the 648,000 digital sets sold since DTV's inception three years ago, only 27,000 have tuners in them. 37
However, the research firm, Cahners In-Stat Group, is forecasting shipments of more than 1.3 million digital monitors and televisions in the United States in 2001. That is more than twice that of last year. They believe that the popularity of DVDs and the availability of digital cable television are driving the sales. Sets in the $500 range should be available by 2005, according to Cahners In-Stat. 38
| Company |
Percent increase of sales for 2001 first quarter |
| Sony |
+736% |
| Hitachi |
+800% |
| Mitsubishi |
+136% |
| Toshiba |
+254% |
| Panasonic |
+224% |
| RCN |
+170% |
| Samsung |
+652% |
| Pioneer |
-8% |
| Philips |
+3,336% |
| Loewe |
-32% |
39
In 2001, the FCC required cable operators to carry digital TV broadcast signals for basic service, but they will not be mandated to require subscribers to obtain set-top boxes to view digital TV signals. Internet and data services that are not related to the primary DTV program will not be required for carriage. 40 Cable doesn't want to carry the broadcasters signal because they feel it would be to their disadvantage. Stephen A. Booth of Brandweek states, "Cable operators fear they'll be compelled to become the delivery boys for the broadcaster's new products." Robert Sachs, president of the National Cable Television Association, stated "It's about an attempt to misuse a government rule to give broadcasters an economic advantage in a competitive new commercial business." 41
The government is concerned with broadcasters using datacasting so much that the public never sees anything better than the old NTSC. Stephen A. Booth, of Brandweek, reports, "Congress have become increasingly alarmed that station owners won't use the free boon of publicly-owned spectrum to transmit ad-supported digital eye candy, but instead will flip their broadband land grant to make a buck on datacasting services possibly subscription-based." It is debatable whether the government can do anything to prevent the stations from using their bandwidth for datacasting. The FCC has stated that, a broadcaster only needs to transmit a single SDTV program to fulfill its commitment. 42
Intel Corporation and PBS aired the first nationally broadcast enhanced digital television program, Ken Burns' Frank Lloyd Wright documentary on November 10, 1998. Companion data was simultaneously transmitted to Intel® Architecture-based personal computers capable of receiving the digital television signals. The trial included six PBS stations. 43
Granite Broadcasting demonstrated a service which broadcast three channels of web video along with a HDTV signal in March 2000. Clint Chao, of SkyStream Networks, which supplied the hardware for the demonstration, said, "What we are showing is something you can't get on the Internet today. It's not TV quality, but it's fast approaching TV quality." 44
Michael Grotticelli of Broadcasting and Cable states that, "That's a feeling I get from everyone I know who has a digital-TV set with a tuner. They brag about it for the first two months, then go quiet because there's nothing noteworthy coming from the set to talk about. Sure, the pictures look good, but…" He believes there is not enough content being produced for consumers to be interested. He also believes that the promotional money that the NAB and CEA are going to use to convince consumers to buy digital sets should be spent on financing the hundreds of producers who would be more than willing to shoot in HD and get their programs on air. He says, "If the goal is significant digital tuner penetration, the industry has to provide consumers something to tune in to see. He also suggests they play Bruce Springsteen's song "57 Channels and Nothing On" at the upcoming CEA/NAB meeting in June. 45
Digital television to the consumer is at best confusing, costly, and seemingly absurd. But updating a more than fifty-year-old standard does come with advantages. In time all of these issues will resolve and probably lead to a better television experience with such possibilities as datacasting, multicasting, and enhanced television. Despite the arguments and confusion, ready or not, digital television is about to become a part of America's television viewing pleasure.
[1] KAET, "KAET-DT Glossary of Terms," http://www.kaet.asu.edu/dtv/glossary.htm.
[2] McConnell, Bill, "DTV More than a Theory?" Broadcasting & Cable, April 10, 2000, pp. 31.
[3] KAET, "KAET-DT Glossary of Terms."
[4] Fibush, David K., "High-Definition Television: Video Testing in a DTV World," SMPTE Journal, February 2000, http://www.broadcastpapers.com/hdtv/TektronixDTV01.htm.
[5] KAET, "KAET-DT Glossary of Terms."
[6] Booth, Stephen A., "Mixed Signals," Brandweek, July 10, 2000, pp. 53.
[7] KAET, "KAET-DT Glossary of Terms."
[8] Booth, Stephen A., pp. 53.
[9] KAET, "KAET-DT Glossary of Terms."
[10] Ibid.
[11] Ibid.
[12] KAET, "A Brief Digital History, "http://www.kaet.asu.edu/dtv/history.htm.
[13] Ibid.
[14] Campbell, Richard, Media and Culture: An Introduction to Mass Communication, St. Martin's Press, New York, 1998, pp. 123.
[15] KAET, "A Brief Digital History."
[16] Ibid.
[17] Campbell, Richard, pp. 123.
[18] Mui, Ylan, "Leaping for High Definition," New Orleans Magazine, January 2001, pp. 32.
[19] Booth, Stephen A., pp. 52.
[20] McConnell, Bill, pp. 31.
[21] Grotticelli, Michael, "Something to Watch," pp.1-2.
[22] Booth, Stephen A., pp. 53.
[23] KAET, "KAET-DT Glossary of Terms."
[24] PBS Digital Television, "'Enhanced' Television Catches up with the PBS Mission," http://www.pbs.org/digitaltv/enhanceNS.html.
[25] KAET, "KAET-DT Glossary of Terms."
[26] McConnell, Bill, pp. 30.
[27] Grotticelli, Michael, "The Need for Common Ground," Broadcasting & Cable, April 16, 2001, pp. 1.
[28] Ibid, pp. 30.
[29] Linderman, Carl, "Road to NAB Multimedia: Datacasting Companies put Best Bit Forward," Broadcasting & Cable, April 9, 2001, pp. 52.
[30] KAET, "KAET-DT Glossary of Terms."
[31] Linderman, Carl, pp. 52.
[32] KAET, "KAET-DT Glossary of Terms."
[33] Race, Tim, "Most Wanted: Drilling down/digital television," The New York Times, May 21, 2001, pp. C10.
[34] McConnell, Bill, pp. 30.
[35] Campbell, Richard, pp. 123.
[36] Tarr, Greg, "Change at Top Sparks FCC Action," Twice, January 29, 2001, pp. 14.
[37] Grotticelli, Michael, "Something to Watch," pp. 2.
[38] Race, Tim, pp. C10.
[39] Ibid.
[40] Tarr, Greg, pp. 1, 14.
[41] Booth, Stephen A., pp. 53.
[42] Ibid.
[43] PBS Digital Television.
[44] Jessell, Harry A., "Broadcasting's Killer App?" Broadcasting & Cable, March 27, 2000, pp. 10.
[45] Grotticelli, Michael, "Something to Watch," pp. 2.
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