Advanced Audio Coding (MPEG-2).
FCC Advisory Committee on Advanced Television Service.
A coded representation of a presentation unit. For audio, an
access unit is the coded representation of an audio frame; for
video, an access unit is the coded representation of a picture.
Acknowledge signal (type II and type II handshake).
A/D or ADC
Analog-to-Digital Converter. A circuit that converts an analog
signal, having a continuously varying amplitude, to a digitally
quantized representation using binary output signals.
Adaptive Differential Pulse Code Modulation.
Analog Display Services Interface (type III protocol). A
subscriber feature than enables transfers and display of larger
amounts of data.
Asymmetrical Digital Subscriber Line. A twisted-pair-based
distribution system providing transmission rates up to 6.3 Mb/s.
Advanced Digital Television. An HDTV system
proposed by the Advanced Television Research Consortium,
consisting (in 1992) of David Sarnoff Research Center, North
American Philips, Thomson Consumer Electronics, NBC, and
Compression Labs, Inc.
Alternative Frequencies. This list is compiled in memory within
the receiver of nearby broadcast stations that carry the same
program. This is to allow the motorist who is traveling away
from his local station to automatically switch to the next
geographically located station for continuation of the same
program (such as NPR).
Automatic Frequency Control.
Image artifacts in captured images caused by significant energy
in the scene at frequencies higher than the Nyquist limit of the
sensor. In single-chip color cameras, aliasing can produce
unexpected color patterns in highly detailed monochrome objects.
Application-specific integrated circuit. An IC designed for a
custom requirement, frequently implemented in a gate array or
field programmable array.
Amplitude Shift Keying. A digital amplitude modulation method.
Adaptive Transform Coding.
1. Asynchronous Time Multiplex.
2. Asynchronous Transfer Mode.
Adaptive Transform Acoustic Coding (Sony).
Advanced Television. The term is often used interchangeably with
The signal range from 20 Hz to 20 kHz, according to the standard
specification, although there is some evidence of acoustic
perception outside that bandwidth in exceptional individuals,
particularly young children.
Additive White Gaussian Noise.
British Broadcasting Corporation.
Bit Error Rate. A measure of the probability of bit error in a
The rate at which the compressed bitstream is delivered from the
channel to the input of a decoder.
Block Matching Algorithm.
Bits per pixel (picture element or pel).
The aspect of perception that changes as the intensity of a
patch of light is varied.
A bit in a coded bitstream is byte-aligned if its position is a
multiple of 8 bits from the first bit in the stream.
Conditional Access. A mechanism by which the user access to
service components can be restricted.
alerting signal (type II and type III handshake).
Conditional Access Table, provides the association between one
or more conditional access systems, their entitlement management
message streams, and any special parameters associated with
Community Antenna Television.
Coded Block Pattern.
Coded Block Pattern for luminance.
Constant Bit Rate. An operation in which the bit rate is
constant from start to finish of the compressed bitstream.
Charge-Coupled Device. A type of silicon integrated circuit used
to convert light into an electronic signal.
Channel Compatible DigiCipher. An HDTV
system proposed by the American Television Alliance, consisting
of General Instruments and Massachusetts Institute of
Centre Commun D'Etudes de Telecommunications et de
International Telegraph and Telephone Consultative Committee. A
standardization body for telecommunications.
Code-division multiple access, based on spread-spectrum code
Correlated Double Sampling, a circuit commonly used to process
the output signal from a CCD
image sensor in order to reduce low-frequency noise components.
Consumer Electronics Bus. A multimedia distribution system in
Code-Excited Linear Predictive coding.
Color Filter Array. A mosaic or stripe layer of colored
transmissive filters fabricated on top of an imager in order to
obtain a color image from a single-image sensor.
Call Identification Delivery on Call Waiting (type II). A
subscriber feature that allows for the display of the time,
date, number, and other information about the caller to the
called party while the called party is off-hook.
1. Common Intermediate Format.
2. Common Interleaved Frame, the serial digital output from the
main service multiplexer, which is contained in the main service
channel part of the transmission frame. It is common to all
transmission modes and contains 55,296 bits (i.e. 864 Cus).
Complex Instruction Set Computer. A standard computing approach
taken by Intel and MC68000 microprocessors.
Custom Local-Area Signaling Service. A set of services and
enhancements provided to customers that may include CND,
message waiting, and other features.
Calling Line Identification Delivery (type I). A subscriber
feature that allows for the on-hook display of the time, date,
number, and other information about the caller to the called
Constant Modulus Algorithm for updating tap-weight coefficients
in blind equalization.
Coherent Multilevel Frequency Shift Keying.
Calling Name delivery. A subscriber feature that allows for the
display of the time, date, number, and name of the caller to the
Calling Number Delivery. A subscriber feature that allows for
the display of the time, date, number, and other possible
information about the caller to the called party.
Centre National d'Etudes de Telecommunications.
Central Office. A main telephone office, usually within a few
miles of a subscriber, that houses switching gear. Commonly
capable of handling about 10,000 subscribers.
Also called compression or bit rate reduction, the process of
taking a signal and reducing the number of bits, energy, time,
or bandwidth necessary for its transmission. In the context of
this chapter, coding refers specifically to bit rate reduction
of a digitally captured or encoded signal.
Color Pixel Reconstruction
An algorithm that creates a fully populated color image record
from the output of a CFA-type
sensor by interpolating values for each color at each pixel
A measure of the difference in intensity between two adjacent
patches of light.
The coding procedure that generates redundancy in the
transmitted data stream in order to provide ruggedness against
Customer Premises Equipment, a term used to define a class of
consumer devices found in the hope that connect to a public
network. Examples include a set-top box, telephone, satellite
receiver, personal computer with a modem, answering machines,
and fax machines.
Call Progress Tones, DTMF
tones sent while off-hook to signal-enhanced features.
Cyclic Redundancy Check, verifies the correctness of data.
Composite Second Order. A clustering of second-order frequency
beats at 1.25 MHz above the visual carriers in cable systems.
Constraint System Parameters Stream. An MPEG-2
program stream that conforms to the founds specified in the
MPEG-2 system layer specification.
Clock-Time and Date, Coordinated Universal Time (UTC) code can
be used to set the clock to the exact time as displayed on the
Cordless Telephone-2. A second generation cordless telephone
system introduced in Great Britain in 1989.
Composite Triple Beat. A clustering of third-order frequency
beats around the visual carriers in cable systems.
Data Access Arrangement. A CPE
interface to network, complying with title 47, part 68 of the
Code of Federal Regulations.
Digital Audio Broadcasting.
Digital Audio Tape.
Digital Audio-Visual Council. A nonprofit association whose
purpose is to identify, select, augment, develop, and obtain the
endorsement of formal standards bodies of specifications of
interfaces, protocols, and architectures of digital audiovisual
applications and services.
Displaced Block Difference.
Direct Broadcast Satellite. A digital system for
sending/receiving an MPEG-2
transport stream providing audio/video and data services from a
stationary satellite to a small receiving antenna.
Digital Compact Disc.
Digital Circuit Multiplex Equipment.
Digital Communication System-1800, which is an extension of the
Global System for Mobile Communications standard in the 1800-MHz
band for personal communication networks.
Discrete Cosine Transform.
Decision-Directed Carrier Recovery. A carrier recovery scheme
that uses the decisions feedback from the receiver bit or symbol
decision detection circuit.
Digital European Cordless Telephone. A cordless telephone
standard developed by the European Telecommunications Standards
Institute in 1992.
Depth of Field
The difference between the maximum and minimum distances from a
camera to objects in a scene that can be captured in acceptably
Decision Feedback Equalizer. A nonlinear equalizer consisting of
a feed-forward equalization filter and a feedback equalization
An electronic camera that captures images using a solid-state
image sensor, and then outputs a digital signal representing the
images or records the images on a digital storage medium.
Discrete memoryless channel, which is specified by the
transition probabilities of input and output symbols.
Discrete multitone. A multicarrier modulation scheme.
Differential Pulse Code Modulation.
Digital Spectrum-Compatible HDTV. An HDTV
system proposed by Zenith Electronics and AT&T in 1992.
1. Digital Storage Medium. A digital storage or transmission
device or system.
2. Direct Sequence Modulation. A spread spectrum modulation
scheme that directly modulates the information-bearing data with
a spreading code sequence.
Digital Storage Medium Command and Control. A protocol intended
to provide the basic control functions and operations specific
to managing an MPEG-2
system bitstream on digital storage media.
Digital Signal Processor. An architecture, based on the Harvard
machine, that uses separate data and instruction buses as well
as certain instructions optimized for signal processing, such as
Dual-tone multifrequency, a tone-dialing system based on
outputting two non-harmonic-related frequencies simultaneously
to identify the number dialed or signal call progress. Eight
frequencies have been assigned to the four rows and four columns
of a typical keypad.
Decoding Time Stamp. A field that may be present in a PES
packet header that indicates the time that an access unit is
decoded in the system target decoder.
Digital Television Terrestrial Broadcasting.
Digital Video Broadcasting.
Digital Versatile Disc. A high-density CD-ROM technology that
provides capacity for full-length MPEG-2
movies as well as data and audio storage and playback. (Also
called Digital Video Disc.)
European Broadcast Union.
Entitlement Control Message. Private conditional access
information that specifies authorization levels or the services
of specific decoders.
A signal-processing operation that accentuates edge details
within an image to increase the apparent sharpness. Such
operations may also be called aperture correction, sharpening,
Electronic Industries Association. A standard-setting body for
Electronic Industries Association -- National Radio Systems
The transmitted signal comprising a set of regularly and closely
spaced orthogonal carriers. The ensemble is the entity that is
received and processed. In general, it contains program and data
End of Block.
Enhanced Other-Networks Information. This feature can be used to
update the information stored in a receiver about program
services other than the one being received. Alternative
frequencies, the PS
name, traffic programs, announcement, identifications, and other
information can be used to provide linkage to such other
Elementary Stream. A generic term for one of the coded video,
coded audio, and other coded bit data in PES
Emergency Warning System. This is intended to be used for the
coding of audio and digital emergency and alerting messages.
Such codes can be coordinated with national emergency and
A method for setting the appropriate lens aperture and exposure
time for a scene to be captured.
Frequency-Division Multiple Access, based on frequency
Forward Error Correction.
Fast Fourier Transform.
Frequency-Hopping Modulation. A spread-spectrum modulation
scheme that is used to nonlinearly modulate a train of pulses
with a sequence of pseudorandom frequency shifts.
Fast Information Block. A data burst of 256 bits. The sequence
of FIBs is carried by the fast information channel. The
structure of the FIB is common to all transmission modes.
Fast Information Channel. A part of the transmission frame
(comprising the fast information blocks) that contains the
multiplex configuration information, along with optional service
information and data service components.
Finite Impulse Response. Commonly referring to an implementation
structure of a filter.
Frequency- and Phase-Locked Loop.
Fractionally Spaced Equalizer, whose tap spacing is a fraction
of a data symbol duration.
Frequency-Shift Keying. FSK uses the data stream to modulate a
A type of image sensor consisting of a single light-sensitive
array of photoelements that also store the image during the
sensor readout period.
Grand Alliance. A U.S. HDTV
consortium consisting of General Instruments, Zenith
Electronics, AT&T, David Sarnoff Research Center, Thomson
Consumer Electronics, North Philips Electronics, and
Massachusetts Institute of Technology.
A signal-processing operation that changes the relative signal
levels in order to adjust the image tone reproduction, typically
to correct for the nonlinear (nonunity gamma) light
output-versus-signal input characteristic of the display. The
relationship between the camera light input and the camera
output signal level, called the optoelectronic conversion
function (OCEF), provides the camera's gamma correction curve
Gaussian Minimum Shift Keying. A minimum shift keying with
Gaussian frequency pulse shaping.
Group of Blocks.
Global Positioning System. A satellite ranging system based on
direct sequence spread spectrum for mobile users to determine
Global System for Mobile Communications. A second-generation
cellular system standard set by the European Technical Standards
Institute in 1990.
Human Auditory System. The outer, middle, and inner ear along
with the parts of the central nervous system that are involved
in hearing, speech understanding, spatial localization, and
other auditory functions.
A Scandinavian digital terrestrial HDTV
project proposed in 1991.
High-speed Digital Subscriber Line, providing T1 rate services.
High-Definition Television. An advanced digital television
providing high resolution.
Hybrid fiber and coaxial network.
Human Visual System. The eye, optic nerve, visual cortex, and
other parts of the central nervous system involved in seeing and
A type of digital photography system in which original scenes
are captured using traditional silver-halide-based photography,
and the resulting film or prints are scanned to provide digital
images that may be displayed, manipulated, transmitted, etc.
The focus distance of a camera lens that offers the greatest
depth of field. When a camera is focused at the hyperfocal
distance, all objects from half the hyperfocal distance to
infinity are within the camera's depth of field.
Intercarrier Interference, associated with multicarrier
Institute of Electrical and Electronics Engineers.
In-House Application. Data used by the station for internal use.
For example, IH could be used as a remote switch to turn on/off
a remote transmitter site via the studio-to-transmitter link.
Intermodulation, referring to distortions generated by nonlinear
devices in a system.
A process that alters the way image data are encoded in order to
reduce the average size of an image file.
Image Data Format
A specification for storing image data and related information
in a digital file. One example is TIFF, tag image file format,
which can be used to store various types of monochrome or color
A flow diagram that indicates all of the components used to
produce a final image in a digital photography system.
A scanning process in which the distance from center to center
of successively scanned lines is two or more times the nominal
line width, and in which the adjacent lines belong to different
A type of image sensor consisting of a two-dimensional array
containing light-sensitive photoelements adjacent to
light-shielded vertical storage registers.
The part of a signal that is not perceptible to the human user
under the normal circumstances of use. In other words,
irrelevancy is the part of the signal that may be removed at the
encoder, and removed at the decoder, with no loss of content.
Institut fur Rundfunktechnik, Munchen (FRG).
Interim Standard-54. A dual mode standard for U.S. digital
cellular system and Advance Mobile Phone Service based on
time-division multiple access, set by EIA/TIA
Interim Standard-95. An air interface standard for U.S.
code-division multiple access and Advance Mobile Phone Service
dual-mode operation for mobile and cellular users.
Integrated Services Digital Network. A communications network
intended to carry digitized voice, data, and video services
multiplexed onto the public network with rates up to 64 kb/s.
Intersymbol Interface. The additive contribution (interference)
to a received sample from transmitted symbols other than the
symbol to be transmitted.
Industrial, Scientific, and Medical frequency bands 902-928 MHz,
2.4-2.4835 GHz, and 5.725-5.85 GHz.
International Organization of Standardization.
International Telecommunication Union. An intergovernmental
organization responsible for setting global standards.
International Telecommunications Union-Radio Standardization
International Telecommunications Union-Telecommunications
Japanese Digital Cellular.
Just Noticeable Difference. The level at which an observer can
begin to distinguish between an original signal and a
noisy/corrupted/distorted signal. The JND is sometimes referred
to as a threshold or perceptible threshold.
Joint Photographic Experts Group.
Kilobits Per Second.
Linear Equalizer. A linear filter that is used to reduce
Least Mean Square. An algorithm for adaptively adjusting the tap
coefficients of an equalizer based on the use of
(noise-corrupted) estimates of the gradients.
Location and Navigation. This feature gives the following
information on station location: transmitter's state, city,
latitude, and longitude (in the form of a computed grid number).
The loop formed by the two subscriber wires (tip and ring),
connected to the telephone at one end and the central office (or
PBX) at the other end. Generally, it is a floating system, not
referred to ground or AC power.
Linear Predictive Coding. A particular form of redundancy
removal, where a "linear predictor" is created to
remove the redundancy due to vocal tract (or other signal
generation) effects. LPC is commonly used in a speech coder
because this method allows for good tracking of the redundancy
introduced by the human vocal tract.
Line Termination, generally CO
Mean Absolute Error.
Maximum A Posteriori. A detection hypothesis that maximizes the
a posteriori probability.
Megabits Per Second.
Motion Compensation or Model Compliance.
Macroblock type and Coded Block Pattern for Chrominance.
Multiplex Configuration Information. Information defining the
configuration of the multiplex. It contains the current (and in
the case of an imminent reconfiguration, the forthcoming)
details about the services, service components, subchannels, and
the linking between these objects. It is carried in the FIC
in order that a receiver may interpret this information in
advance of the service components carried in the main service
channel. It also includes identification of the ensemble itself
and a date and time marker.
Multicarrier Modulation. A parallel digital modulation scheme
that simultaneously modulates a number of carriers.
Modified Discrete Cosine Transform.
Mixed-Excitation Linear Predictive coding.
A small, think, removable memory unit, containing digital
integrated circuit memory chips, housed in a rugged package.
Millions of Instructions Per Second. A measure of microprocessor
The combination of analog and digital circuits on the same
Multichannel Multipoint Distribution Service. A microwave local
distribution system providing multiple television channel
programs (up to 33 channels) to subscribers.
Minimum Mean-Square Error.
Multichannel Perceptual Audio Coding (AT&T).
Moving Pictures Expert Group.
1. Mobile Switching Center.
2. Main Service Channel. A channel that occupies the major part
of the transmission frame and carries all the digital audio
service components, along with possible supporting and
additional data service components.
Mean Square Error.
Minimum Shift Keying. A special case of continuous phase-FSK
wherein the peak frequency deviation is equal to half the bit
rate, which is the minimum frequency spacing for two
frequency-shift keying signals.
Modulation Transfer Function. A representation of the human
visual system's response to visual stimuli at various
Motion Vector Data.
Noncoherent Multilevel Frequency Shift Keying.
Coding methods that do not remove any information present in the
signal, i.e., that allow for perfect reconstruction of the
original digital input signal. The classic set of noiseless
coders are the information-theoretic coders such as Juffman
coders. Ziv-Lempel coders, and arithmetic coders. However, other
coders -- including subband, transform, and other source coders
-- can be used as noiseless coders in some circumstances. A
particular example is lossless JPEG.
Network Termination. A connection between terminal equipment (TE)
and the network.
Converts two-wire U-interface to four-wire S/T
National Television System Committee. The term also refers to
the current U.S. color television system, which was specified
and developed in 1950-1953.
Output Back-Off. The output power of a power amplifier in a
modulation system that is needed to back off from the saturation
point of the amplifier to avoid nonlinear distortion.
Orthogonal Frequency Division Modulation or Multiplexing. A
multicarrier modulation scheme that involves multiplexing a
number of low-speed modulated carriers for transmission.
The condition in which the telephone is connected to the phone
system, permitting loop current to flow. The central office
detects the DC current as an indication that the phone is busy.
The condition in which the telephone's DC path is open and no DC
loop current flows. The central office regards an on-hook phone
as available for ringing.
An optically transmissive device, such as a stack of
birefringent quartz plates, that limits the high-frequency
content of an image focused on a solid-state image sensor in
order to reduce aliasing.
Offset Quadrature Phase-Shift Keying, where on quadrature arm is
offset by one bit duration relative to the other arm.
Private Automatic Branch Exchange. A customer-owned, switchable
telephone system providing internal and/or external
Perceptual Audio Coding (AT&T).
1. A group of binary digits that is switched as a composite
whole with data, control, and error elements arranged in a
2. A packet consists of a header followed by a number of
contiguous bytes from an elementary data stream.
The mode of data transmission in which data are carried in
addressable blocks called packets. Packets
are used to convey MSC data groups within a subchannel.
Personal Access Communication System. A third-generation
personal communications system originally developed and proposed
by Bellcore in 1992; it later became a radio interface standard
for U.S. Personal Communications Service in the 1920-1930-MHz
Program-Associated Data. Information that is related to the
audio data in terms of contents and synchronization. The PAD
field is located at the end of the DAB
Pulse Amplitude Modulation. A digital amplitude-modulation
Peak-to-Average power Ratio (usually expressed in decibels [dB]
that is used to determine the robustness of a modulated signal
against nonlinear distortion.
Precision Audio Subband Coding (Philips).
Program Association Table. Provides the association between a
program number and the PID
value of the transport stream packets, which carry the program
A generic term referring to the bytes that follow the header
bytes in a packet.
Pulse Code Modulation.
Personal Computer Memory Card Industry Association. A nonprofit
trade association founded in 1989 to define a standard memory
card interface for computers.
Program Clock Reference. A time stamp in the transport stream
from which decoder timing is derived.
Personal Communication Systems or Services.
Pacific Digital Cellular. A cellular standard that was developed
in 1991 to provide for needed capacity in congested cellular
bands in Japan.
A lossy form of coding where parts of the signal that are not
perceptible to the end user are removed. Perceptual coding is
always lossy and is in some sense the dual of source coding,
i.e., "destination coding," where information
important to the destination (human being) is preserved and
information not important is removed.
Packet Elementary Stream. Consists of PES packets, all of whose
payloads consist of data from a single elementary stream, and
all of which have the same stream identifier.
Phase and Frequency Detector used for decision-directed carrier
Photo CD Disc
A compact disc-recordable (CD-R) optical write-once disc that
stores scanned photographic images using the Image Pac image
Personal Handy Phone System. A Japanese air interface standard
set by the Research and Development Center for Radio Systems;
its network interface was specified by the Telecommunications
Technical Committee of Japan in 1993.
Program Identification. This information consists of a code that
enables a receiver to identify the program. The code is not
intended for direct display to the user, rather it is sort of a
program ID to allow distinction from all other programs. This is
valuable for "scanning" and "learning"
receivers (with or without memory), which are equipped to switch
over to an alternate transmitter with the same program (NPR
radio affiliates, for example, often broadcast the same program
at the same time).
Packet Identifier. A unique integer value used to associate
elementary streams of a program in a single or multiple program MPEG-2
Program Item Number. A number that can be used by a "smart
radio" to tune a specific program at a particular time when
the program has come on the air. It allows for consumer
convenience in receiving special programs.
Pixel, Pel, Picture Element
The smallest area of a television picture capable of being
delineated by an electric signal passed through the system or
part of it.
Program Map Table. Provides the mappings between program numbers
and the elementary streams that make up the program.
Plain Old Telephone Service.
Pel Recursive Algorithm.
A collection of elementary streams with a common time base.
Program Service. This is a text of not more than eight
alphanumeric characters coded in conformity with the standard
and used to display the service name of the broadcasters.
Examples of PS names are "WABC," "WXYZ,"
"G-100," "HOT93," or "COOL99".
Program Type. This is an identification number to be transmitted
with each program; it will identify the "type" or
"category" of the program content. There are 31 codes
allowed and in the RBDS U.S. standard, 22 categories plus
emergency alert have been decided on. 15 is for classical music,
and the display will show "CLASSICL" -- lacking the
"A" because only eight characters are allowed.
Program-Type Name. An alternate name to be displayed after the PTY
search if the broadcaster wants to give a more specific music
Progressive (Sequential) Scanning
A rectilinear scanning process in which the distance from center
to center of successively scanned lines is equal to the nominal
Program Stream. Consists of contiguous PES
packets that comprise one or more video or audio elementary
Program-Specific Information. Consists of normative data
necessary for the demultiplexing of transport streams and the
successful regeneration of programs.
Pitch-Synchronous Innovation Code Excited Linear Predictive
Phase-shift keying. A digital phase-modulation scheme.
Peak Signal-to-Noise Ratio.
Public Switched Telephone Network.
Presentation Time Stamp. A field that may be present in a PES
packet header that indicates the time that a presentation unit
is presented in the system target decoder.
Presentation Unit. A decoded audio frame or a decoded picture.
Quadrature-Amplitude Modulation. A combined phase- and
amplitude-modulation scheme that is used to modulate the carrier
signal in phase quadrature.
Qualcomm Code Excited Linear Predictive coding.
Quadrature or Quaternary Phase-Shift Keying. A digital
phase-modulation scheme that is used to modulate the carrier
signal in phase quadrature.
A process by which information, redundancy, and irrelevancy are
removed from a signal. A quantizer is a construct that takes an
amplitude-continuous signal and converts it to discrete values
that can be reconstructed by a decoder.
To subdivide the range of values of a variable into a finite
number of nonoverlapping subranges or intervals, each of which
is represented by an assigned value within the subrange.
The process of beginning to read and decode the coded bitstream
at an arbitrary point.
Parts of a signal that are, because of the process(es) that
generated it, predictable or in some way related to other parts
of the same signal. In a strict sense, redundancy in a signal is
not part of the information content of that signal as it may be
removed at the encoder, and restored at the decoder, with no
loss of content.
Radio frequency that is above the audio and below infrared
frequencies. The frequency range is 10 kHz to 10 GHz, allocated
for radio use.
One of the two wires connecting the central office to CPE.
The name derives from the ring portion of the plugs used by
operators in older equipment to make the connection. Ring is
traditionally negative with respect to tip.
Reduced Instruction Set Computer. A CPU architecture that
optimizes processing speed by using a smaller number of basic
Standard four-wire analog phone connector.
Standard eight-wire ISDN
Radio Paging. The RP feature is intended to provide for numeric
and alphanumeric paging via the FM radio transmitter. Already,
several international paging operations are in progress. RDS
paging receivers are not unlike those already in the
marketplace; they are merely operating at a different frequency
and from an already installed transmitter.
Regular Pulse Excited linear predictive coding with Long-Term
Radiotext. For receivers suitably equipped with a display,
messages could be sent to the listener giving information about
the program being broadcast or advertiser-supported messages. A
voice synthesizer could be controlled by the radiotext code, for
example, to enunciate a certain message in the absence of a
Four-wire interface between terminal equipment (TE)
and network termination (NT).
Single-carrier modulation, in which information data is
modulated on one carrier for transmission.
System Clock Reference. A time stamp in the program stream from
which decoder timing is derived.
The alteration of the characteristics of a video, audio, or
coded data stream in order to prevent unauthorized reception of
the information in a clear form.
Society of Cable Telecommunications Engineers.
Spontaneous Call-Wire Identification Delivery (type II) -- see CIDCW.
Sequentiel Couleur Avec Memoire.
Symbol Error Rate. A measure of probability of symbol errors in
a communication system.
Single-Frequency Network. A network of DAB
transmitters sharing the same radio frequency to achieve a
The transmission of control or status information in the form of
dedicated bits or channels of information inserted on lines with
A measure of the perceived difference between two adjacent
patches of light.
Signal Level Meter.
Society of Motion Picture and Television Engineers.
Signal-to-Noise Ratio. The measure of the energy in the signal
(usually expressed in decibels [dB]), within a certain bandwidth
and/or time, versus the energy of the noise that was added to
the signal by some process. In this context, noise refers not
only to added random noise but to any other difference, other
than simple scaling, present in the reconstructed signal. In
video, a variant of SNR called PSNR (peak signal-to-noise ratio)
is often used; this corresponding to the energy of the noise
versus the maximum possible signal energy.
Synchronous Optical Network, which specifies data transmission
over optical fiber with rates ranging from 51.84 Mb/s to 9.95
Techniques that use the redundancy in a signal to reduce the bit
rate. Some source coders (noiseless coders) remove only
redundancy and provide perfect reconstruction of the decoded
signal. Tohers remove redundancy and some information as well
and provide a noisy decided signal, but usually with
unobjectionable noise characteristics. Typical kinds of source
coding are LPC,
Significant pel area.
The concatenation, performed on the system level, of two
different elementary streams. The resulting system stream
conforms totally to the MPEG-2
system standard. The process may result in discontinuities in
time base and decoding.
Spread-spectrum modulation. A digital modulation scheme that
spreads the system bandwidth far greater than the minimum
A 32-bit code word embedded in the coded bitstream that is
unique. The start codes are used for several purposes, including
identifying some of the layers in the coding syntax, and they
consist of a 24-bit prefix (0x000001) and an 8-bit stream ID.
System Target Decoder. A hypothetical reference model of a
decoding process used to describe the semantics of the MPEG-multiplexed
Stream Identifier. An 8-bit unique word used to define a video,
an audio, or other PES
The mode of data transmission within the Main Service Channel,
in which data are carried transparently from source to
destination. Data are carried in logical frames.
A subdivision of the audio frequency range. In the audio coding
system, 32 subbands of equal bandwidth are used.
A part of the main service channel that is individually
convolutionally encoded and comprises an integral number of
capacity units per common interleaved frame.
Still Video Floppy. A standardized recording medium for analog
electronic still cameras developed in the early 1980s. SVF
cameras use a 2-inch-diameter floppy disk capable of storing
either 50 field images or 25 frame images.
A part of the transmission frame provided to ensure proper time,
frequency, and phase synchronization in the receiver.
1. Terminal Adapter. Takes a non-ISDN data stream and converts
it to the ISDN
data format; used to provide S/T
connection to type 2 terminal equipment (non-ISDN-compliant).
2. Traffic-Announcement Identification. This is an indicator to
show when the actual traffic announcement is in progress. It can
be used by the receiver to switch from its current mode over to
the traffic announcement on the main audio channel, and then
back to the previous setting after the traffic announcement
Thomson Consumer Electronics.
Trellis-Code Modulation. A combined coding and modulation
Transparent Data Channel. These channels could be used to send
alphanumeric characters, or other text, or for transmission of
computer program data or similar information not intended to
display on the user's set.
Time-Division Multiple Access. A time-slot-based multiuser
Terminal Equipment. Type 1 (TE1) is ISDN-compliant.
Type 2 (TE2) requires a terminal adapter to connect to the
Usually 200 Hz to 3200 Hz, although some algorithms and
transmission facilities provide signals from 50 Hz to 3600 Hz,
depending on the situation and equipment involved.
Time-Hopping Modulation. A spread-spectrum technique using
pseudorandom time-hop patterns as the spreading sequence code;
it is analogous to pulse-position modulation.
Telecommunication Industry Association. A trade organization
that provides services such as government relations, market
activities, educational programs, and standards-setting
Indicates the time of an event such as the arrival of a byte or
the presentation of a presentation unit.
One of the two wires connecting the central office to SPE. The
name derives from the tip of the plugs used by operators in
older equipment to make the connection. Tip is traditionally
positive with respect to ring.
Test Model for Near-term solution (H.263).
Threshold of Visibility. A bit-error-rate HDTV
threshold of 3 x 10-6, at which value the impairment effect
first becomes visible in the picture.
Traffic-Program Identification. This is a digital flag sent by
the broadcaster to turn on the lamp or other signal within the
receiver to indicate to the user that the broadcaster is giving
traffic announcements (when the lamp does not light, it means
that the station is not giving traffic announcements at the
Timing Recovery for symbol synchronization.
The actual transmitted frame -- specific to the three
transmission modes -- conveying the synchronization channel, the
fast information channel, and the main service channel.
A specific set of transmission parameters (e.g., number of
symbol duration). Three transmission modes (i.e., I, II, III)
are defined to allow the system to be used for different network
configurations and a range of operating frequencies.
Transport Stream. Contiguous packets, each of which is 188-bytes
in length, consisting of one or more PES packets.
Transparent Tone In Band. A pilot-aided carrier recovery
Unequal Error Protection.
A two-wire interface between network termination (NT)
and line termination (LT).
U-interface Terminal Adapter. Converts non-ISDN data stream to ISDN
data format; used to provide U-interface connection to type 2
terminal equipment in North America.
Variable Bit Rate. An operation in which bit rate varies with
time during the decoding of a compressed bitstream.
Variable Length Coding (Decoding).
Variable-Length Instruction Word. A new CPU architecture that
relies on a variable-length word size and small parallel
processors to provide throughput in terms of billions of
operations per second.
Video On Demand.
Vestigial Sideband. The transmitted portion of one sideband; the
sideband is suppressed in a transmitter having a gradual cut-off
in the neighborhood of the carrier frequency. Meanwhile, the
other sideband is transmitted without suppression.
Vector-Sum Excited Linear Predictive coding.
Wireless Access Communication System. Developed to provide
wireless connections for local exchange carriers.
A process for adjusting the relative signal levels of the red,
green, and blue channels from a camera to correct for the color
of the light source illuminating a scene, so that objects that
appear to be white in the scene are reproduced as white on the
soft-display or hard-copy print.
Speech having a bandwidth of 60 Hz to 7 kHz, also referred to as
commentary grade or remote contribution quality.
Wireless Local-Area Network.
Home | Products
Semiconductor | Sony
Support | Search
| Career Opps
Policy | Site
Send email to the Semiconductor
© Copyright 1996-2001 Sony Electronics Inc. All Rights Reserved. Legal/Trademark
Consumer Product e-mail should be sent to Consumer
Customer Service or call 1/800/222-7669.