179
AC 3
Output for Dolby Digital signal
ASTRA
SES (Société Européene des Satellites) satellite system.
Analogue and digital transponders in the frequency range
10.7-12.75 GHz.
AV programme pos.
Preferred programme slot on TV set for external
connections such as Scart and HDMI
CAM – Conditional Access Module
Decryption decoder, which uses a smart card 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 fixed assignment for the
transponder transmission frequency, for polarization
(horizontal or vertical), for the symbol rate and for the
Viterbi rate or error rate.
CI - Common Interface
Internationally standardised interface for CA modules
Conditional Access (CA) system
Controls user access to services and programmes which
are encrypted for reasons of copyright or for commercial
reasons.
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.
DiSEqC™
DiSEqC™ (Digital Satellite Equipment Control) is a
communication system between a satellite receiver
(master) and the peripheral satellite components (slaves),
such as LNBs, multi-switches, rotating antenna systems.
It is a single master/multi-slave system, i.e. there is only
ever one master in the satellite system. All activities start
from the master.
DiSEqC™ components
If DiSEqC™ switching matrices are cascaded, the master
receiver must transmit the DiSEqC™ signal several times,
so that all DiSEqC™ multi-switches in the cascade receive
their commands.
These days, DiSEqC™ components (slaves) must be
downward compatible, i.e. respond to the analogue
switching criteria from receivers that are only equipped
with H/V and kHz control signals.
A DiSEqC™ switching matrix will work with analogue
switching criteria until the DiSEqC™ command from the
master is received. All analogue switching criteria are then
ignored.
Dolby Digital 5.1
Dolby Digital is a sound transmission that allows digital
surround sound to be output on a home cinema system.
DVB - Digital Video Broadcasting
DVB-S refers to the transmission method (S = satellite,
C = cable, T = terrestrial).
DVB-S2
An enhanced DVB-S signal for HDTV with better quality.
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.
EUTELSAT
European Satellite operator, based in Paris. Many orbit
positions and European customers. Transponders in the
frequency range 10.7-12.75 GHz.
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
Encryption 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.
Brief Technical Glossary
