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Brief Technical Glossary
AC 3
Output for Dolby Digital signal
AV programme pos.
Preferred programme slot on TV set for external
connections such as Scart and HDMI
Conditional Access (CA) system
Controls user access to services and
programmes which are encrypted for reasons of
copyright or for commercial reasons.
CAM – Conditional Access Module
Decryption decoder, which uses a smartcard to
decrypt the encrypted radio and TV signals.
Channel package
The channel package for a digital transponder
normally includes several TV and radio channels.
Each channel package has a fi xed assignment
for the transponder transmissionfrequency,
for polarisation (horizontal or vertical), for the
symbol rate and for the Viterbi rate or error rate.
CI - Common Interface
Internationally standardised interface for CA
modules
Data rate
Data bits transmitted per second. Is expressed
in kbit/s or Mbit/s. The higher the data rate the
better the quality of the transmitted signal.
Data reduction
Compression of video and audio signals.
Redundant information is discarded.
Dolby Digital 5.1
Dolby Digital is a sound transmission process that
allows digital surround sound to be output on a
home cinema system.
DVB - Digital Video Broadcasting
DVB-C refers to the transmission method
(C = cable, S = satellite, T = terrestrial)
Eb/No ratio
The Eb/No ratio is a measure of the signal-to-
noise ratio of a digital signal. The value is not
identical to the C/N value familiar from analogue
reception technology. At Eb/No values below 5 dB
no reception is normally possible.
FEC
FEC is the abbreviation for "Forward Error
Correction". A technique for reducing the error rate
of data transmission. Additional bits are inserted
into the data stream, so that error-correction
algorithms can be used on reception. The FEC
error rate corresponds to the Viterbi rate.
HD – Ready
This is a label created by the EICTA (European
Information, Communications and Consumer
Electronics Industry Technology Association) for
equipment that is capable of reproducing HDTV.
HDCP – High-bandwidth Digital Content
Protection
Coding system which protects the HDMI and DVI
interfaces for secure transmission of video and
audio data. HDCP should be used in Europe for
HDTV standard transmissions.
HDMI - High Defi nition Multimedia Interface
Digital interface for digital video and audio data
transmission (preferred for HDTV).
HDTV – High Defi nition Television
High resolution television with a resolution up
to 5 times higher or fi ner than PAL or NTSC.
However, there is no compatibility, as the
compression technique MPEG-4 is used for
broadcasting in the transmission process DVB-S2.
The principal features of HDTV are the larger
picture format (16:9), the doubled number of
scanning lines (increased from the currently
625 to 1,250) and digital sound quality.
H.264
Another name for MPEG-4.
IP address
Internet Protocol address (for automatic linking of
a PC/laptop into an existing network)
MPEG-2
MPEG is the abbreviation for Moving Picture
Experts Group, a working group that formulates
internationally applicable standards for the
digital compression of video and audio. MPEG-2
has become established as the standard for
compression of digital TV signals. MPEG-2 works
up to a data rate of 100 Mbit/s.
