Appendix G Acronyms and Glossary

Acronyms

—heIiCan Electrom“CS ksociatiq table z-s. MMDs —Multichannel Multipoint Distribution fk&cD —Active Matrix Liquid Crystal Display Service —ArnericanNational Standards Institute, table —Multi-media Terminals 2-3. MFAA —Motion Picture Association of America, ASK —Application Specific Integrated Circuit table 2-3. ATSC —Advanced Television Standards committee, —The Japanese Ministry of Posts and table 2-3. Telecommunications AmC —Advanced Television Test Center, table 2-3. MUSE —Multiple sub-Nyquist Sample Encoding Am —Advanced Television NAB —National Association of Broadcasters, table BTA —Broadcast Technology Association 2-3. CM’S —Center for Advanced Television Studies, N(XA —NationalCableTelevision Association, table table 2-3. 2-3. cm -Charge-Coupled Device —Nippon Hoso Kyokai (Japan) CCIR —Comite Consultatif International des NTIA —National Telecommunications and Radiocomrnunications Information Administration CD -Compact Disk NTsc —National Television Systems Committee DARPA —Defense Advanced Research Projects PAL —Phase Alternation by Line Agency (DoD) SECAM —Sequential Encoded Color Amplitude Modulation DAT —Digital Audio Tape SMATV —Satellite Master Antenna Television —Direct Broadcast Satellite DBS SMPTE —Society of Motion Picture and Television DoD —U.S. Department of Defense Engineers, table 2-3. DRAM —Dynamic Random Access Memory TvRo —Television Receive Only DSP —Digital Signal Processor —Ultra High Frequency DVI —Digital Video Interactive VCR —Video Cassette Recorder EBU —European Broadcasting Union —Very High Frequency EDTV —Extended- or Enhanced-Definition VHs —Video Home System Television —Video Random Access Memory EIA —Electronic Industries Association, table 2-3. EIAJ —Electronic Industries Association of Japan. Glossary FCC —Federal Communications Commission 525/59.94; 625/50: The number of scan lines followed by FSS —Fixed Satellite Services the field rate for the existing NTSC (U. S., Japan, etc.), GHz -Gigahertz PAL (Europe except France, China, etc.), SECAM HD-MAC —High Definition Multiplexed Analog (France, Soviet Union, etc.) color TV systems. Component 1050/59.94; 1125/60; 1250/50: The number of scan lines HRs —High Resolution Systems followed by the field rate for various HDTV system HDTV —High Definition Television proposals, corresponding to the United States, Japan, IC —Integrated Circuit. and Europe, respectively. IDTV —Improved Definition Television Active Matrix Liquid Crystal Display (AM/LCD): An IEEE —Institute of Electrical and Electronics advanced type of liquid crystal display. Engineers, table 2-3. Advanced Television (ATV): Refers generically to all ISDN —Integrated Services Digital Network the improvements in TV over today’s system, includ- ITFs —Instructional Television Fixed Service ing IDTV, EDTV, and HDTV. —International Telecommunications Union Application Specific Integrated Circuit (ASIC): A type —Kilohertz of integrated circuit produced in relatively limited LCD —Liquid Crystal Display numbers for a specific application. LPTV —Imw-Power Television Artifact: An audio or video error or defect introduced —Megahertz during the processing or transmission of a TV signal. —The Japanese Ministry of International Trade Aspect Ratio: the ratio of a screen’s width to its height. and Industry Today’s TVs have a 4:3 aspect ratio. HDTV systems MSO —Multiple System Operator typically call for a 5:3 or 16:9 ratio.

–lo6- Appendix Mcronyms and Glossary ● 107

Bandwidth: The range of frequencies available for or bits), etc. The storage capacity of a computer or other used to carry an electronic signal. systems is measured in bytes-1 KB, MB, etc.—and Beta: The first, but less popular, format for home VCRs. one byte equals 8 bits. Bit Rate: The rate at which digital data is carried or Eureka 95: The joint project to develop Am systems for transmitted, measured in units of bits (binary digits) Europe. per second. This is the digital equivalent of an analog European Broadcasting Union (EBU): A union of bandwidth. European broadcast organizations whose purpose is, Broad Band: A signal that requires a large bandwidth to among others, to develop standards for the exchange of be transmitted or equipment that must be capable of program material among its members. receiving and transmitting accurately a signal with a Extended- or Enhanced-Definition TV (EDTV): A large bandwidth. form of TV that provides a better picture than today’s Broadcast Technology Association (BTA): An or- TV or IDTV using today’s broadcasts, but somewhat ganization of private Japanese broadcasters and equip- less resolution than HDTV. EDTV requires modest ment manufacturers. changes in today’s NTSC broadcast signal, but is C-Band: The range of frequencies from 4 to 6 GHz. See compatible with it while remaining within today’s figure 3-1. channel bandwidths. EDTV usually has a greater than Cable TV Labs: A lab setup by the N(2TA to test cable 4:3 aspect ratio. systems, including those for ATV, table 2-3. Federal Communications Commission (FCC): The Charge-Coupled Devices (CCD): A type of solid-state U.S. Government agency dealing with communica- electronic device used as a sensor in some types of tions issues and allocation of the radio frequency careers. spectrum. ClearVision: The Japanese EDTV system. FCC Advisory Committee on Advanced Television Comite Consultatif International des Radiocommu- Service: The industry committee set up by the FCC to nications (CCIR): An organization under the ITU make recommendations on advanced television system which studies technical questions and issues recom- broadcasting standards. mendations for international radio matters. Fiber: Optical fibers used to carry information, usually in Compact Disk (CD): An opticaI storage medium used for the form of pulses of light. music and for computer data, among others. Field: The alternate lines that compose half of a complete Compatibility: The ability of one type of TV set to television picture or frame. In the United States, fields receive and display the signals designed for another are shown at a rate of 59.94 fields per second; in TV system. See box 4-3. Europe, fields are shown at a rate of 50 fields per Digital Audio Tape (DAT): A new technology that second. records music on magnetic tape in a digital format. Fixed Satellite Services (FSS): Satellites that are as- DAT has many applications to computer data storage. signed geostationary orbits and provide information Digital Signal Processor (DSP): A type of digital chip transmission services. that manipulates a video (in the case of HDTV) signal. Frame: A complete television picture, including both For the purposes here, this manipulation is usually to even and odd alternating scans. The frame rate in the either compress the signal so that it can be transmitted United States is 29.97 ties per second; in Europe, it or decompress it and turn it back into a viewable is 25 frames per second. If frames are shown at too picture. slow a rate, there can be an annoying flicker to the Digital Video Interactive (DVI): A digital technology in picture. which the viewer can interact with the image being Gigahertz (GHz): One billion cycles per second. shown. For example, a viewer might take a video Headend: A cable TV system’s control center where ‘‘walk’ through a building being designed by an incoming signak from satellites and other sources are architect and see the details of the interior or view the put on cables going to subscribers. building from any desired angle, at that person’s Hertz (Hz): Cycles per second. One kHz is 1,000 cycles discretion. per second; one MHz is 1 million cycles per second; Direct Broadcast Satellite (DBS): It transmits TV one GHz is 1 billion cycles per second. signals directly to satellite receiver dishes at viewer’s High Definition Multiplexed Analog Component (HD- homes. DBS is a high-power system that requires only MAC): The European HDTV system for DBS deliv- small dishes. ery. Downlink: The transmission (or receiver system) from a High Definition TV (HDTV): Usually defined as having satellite. roughly twice the resolution of today’s TV systems, a Dynamic Random Access Memory (DRAM): A com- wider aspect ratio of 5:3 or more, and compact disk puter memory chip. The capacity of DRAMs is quality sound. measured in bits—lKb (1,000 bits), IMb (1 million High Resolution Systems or High Definition Systems 108 . The Big Picture: HDTV and High-Resolution Systems

(HRS): Information systems that provide a high National Television Systems Committee (NTSC): The resolution visual image. See box 1-1 for examples. industry group that defiied the current U.S. B&Wand HiVision: The Japanese HDTV system based on their then color TV standards. The NTSC system is used in MUSE standard. the United States, Cana@ Japan, and elsewhere. Improved Definition TV (IDTV): A television that uses Nippon Hoso Kyokai (NHK): The national radio and digital technologies to improve the picture seen even television broadcasting organization for Japan. Has with today’s conventional broadcasts. extensively funded and coordinated HDTV develop- Instructional Television Fixed Service (ITFS): A TV ment in Japan. delivery service by line-of-sight microwave that the Optical Disks: Recording media including CDs that store FCC licenses for use by educational institutions. information in patterns of microscopic pits on the Integrated Services Digital Network (ISDN): A fully surface of the disk, which can then be detected by a digital telephone network now being implemented. solid state laser and detector system and reproduced as This system makes use of the existing copper wire sound, images, or data. infrastructure but adds improved electronics which Pay Per View: Program services purchased by sub- allow much higher data rates to be carried. scribers on a per-program rather than per-month basis Interlaced Scan: A technique which first shows all the Phase Alternation by Line (PAL): The type of TV even lines of the TV picture or frame, and then shows system used in most European countries (with the all the odd lines of the frame. Each set of lines notable exception of France), The People’s Republic corresponds to one field. This allows the picture to be of China, Australia, and elsewhere. shown without flicker while reducing the total band- Progressive Scan: A TV picture that is shown in a single width necessary to transmit the picture. scan—the way we read a book-rather than by International Telecommunications Union (ITU): An alternately sending all even and all odd Lines as for an intergovernmental organization with 164 member interlaced scan. countries, whose purpose is to develop regulations and Resolution: A measure of a picture’s detail. voluntary recommendations, provide coordination of Satellite Master Antenna Television (SMATV): Or telecommunication development, and foster technical ‘‘private cable”; a miniature cable system that receives assistance fo developing countries. The CCIR is one of programming by satellite and serves a housing com- the organizations under the IT’U. plex or hotel. Kilohertz (kHz): One thousand cycles per second Sequential Encoded Color Amplitude Modulation Ku-Band: The range of frequencies between 11 to 14 (SECAM): The TV system used today in France, the GHz. See figure 3-1. Soviet Union, and elsewhere. Liquid Crystal Display (LCD): The type of display used Taboo Channel: A TV channel left unused in order to on calculators and watches. prevent interference on adjacent active TV channels in Low-Power TV (LPTV): Stations licensed by the FCC the same geographic area. to use low transmitter power, usually in areas not Television Receive Only (TVRO): A satellite receiving locally sewed by full-power stations. antema, also known as a downlink or a bac~ard dish. Megahertz (MHz): One million cycles per second. Transponder: A satellite component that receives and Multichannel Multipoint Distribution Service (MMDS): retransmits a TV signal or perhaps many narrower- A TV delivery system using line-of-sight microwave band data channels. with four or more channels operated by a single Ultra High Frequency (UHF): The band including TV company. MMDS is often called wireless cable’ and channels 14 through 83. See figure 3-1. is similar to I’I’FS in operation. Uplink: The transmission or corresponding equipment to Multi-media Terminals (MMT): Computer terminals a satellite for relay. that can combine normal text and graphics with Very High Frequency (VHF): The band including TV near-real-time video images or other forms of visual channels 2-13, which are more powerful than UHF display. channels. See figure 3-1. Multiple System Operator (MSO): A company that Video Cassette Recorder (VCR): Piece of equipment operates more than one cable TV system. used for recording and replaying TV broadcasts or Multiplex: See box 3-1. prerecorded video materhd at home. Multiple Sub-Nyquist Sampling Encoding (MUSE): Video Home System (VHS): The most common format The bandwidth compression technique developed by for today’s VCRs. Japan’s NHK to allow delivery of an HDTV quality Video Random Access Memory (VRAM): A type of signal over a DBS system. memory chip similar to a DRAM, that is optimized for National Telecommunications and Information Ad- high-speed handling of video images. ministration (NTIA): A U.S. Government agency Sources include: “Behind the Buzzwords,” Channels/Field Guide, under the Deparrnent of Commerce. 1989; and “Everyone’s Thlking About HDTV, But What &e The Facts?” Ampex, Redwood City, CA, 1989.