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User Guide
APPENDIX 6 Glossary
AC-3
Audio Code 3
– A Dolby digital audio encoding scheme. The audio encoding format adopted by the ATSC.
ATSC
Advanced Television Systems Committee
BER
Bit Error Rate - The number of erroneous bits divided by the total number of bits over a stipulated period of time.
Usually expressed as a number and a power of 10.
Bit
An indivisible unit of digital data represented as 1 or 0.
bps
Bits per second
Broadcast
A service that is delivered to all subscribers. Each subscriber may select a particular broadcast channel
out of many.
Byte
An octet of associated bits
Cable
Cable Television Systems
Carrier
An RF signal used to carry information (video, audio, data) by some modulation scheme.
Coax
Coaxial Cable
Composite video
A baseband representation of a video signal containing luminance and chrominance information.
C/N
Carrier to Noise Ratio
dB
Decibel - A logarithmic value of a ratio
dBc
Decibels relative to carrier amplitude
dBm
Decibels relative to one milliwatt
dBmV
Decibels relative to one millivolt across a given impedance (75 ohms in North American cable systems)
DTV
Digital Television
– A general term for the digital coding and transmission of an Audio / Video Program.
EIA
Electronic Industries Alliance
ES
Elementary Stream
– A generic term for a stream of data of one particular type. Typically these streams are of
Video or Audio Types.
FCC
Federal Communications Commission.
Headend
The control center of a cable television system, where incoming signals are amplified, converted,
processed, and combined into a common cable, along with any locally originated programming, for transmission to
subscribers.
HRC
Harmonically Related Carrier
IF
Intermediate Frequency. A signal processing stage between RF and baseband.
IP
The network layer (layer 3) of the OSI Internet protocol, providing connectionless datagram service.
IRC
Incrementally Related Carrier
kbps
Kilobits per second- bits per second in thousands
kHz
Kilohertz - Cycles per second, in thousands
Mbps
Megabits per second- bits per second in Millions
