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SHORT TECHNICAL GUIDE
Channel package
The channel package normally includes several TV and radio channels. Each programme package has
a fi xed assignment for the transmission frequency, for polarisation (horizontal or vertical), for the symbol
rate and for the Viterbi rate or error rate.
DVB MPEG-2
DVB is the abbreviation for Digital Video Broadcasting. DVB-T refers to the transmission method
(T = terrestrial). 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 MB/s.
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. The FEC error rate corresponds to the Viterbi rate.
PID
The PID (Packet IDentifi cation) number is an identifi cation number for video signals and audio signals
in the digital data stream of DVB MPEG-2 signals. The receiver uses the PID number to create a
unique assignment for the video and audio data transmission. The PCR PID is the identifi cation
number for the synchronization signal. The PID-PCR is normally identical to the video PID. For
programmes broadcast in multiple languages, the audio PD can be entered manually to assign a
different language to the TV programme. After the PID is entered, the digital receiver automatically
selects the audio data identifi ed by the PID number from the data stream and assigns it to the
video signal.
Symbol Rate
The symbol rate describes the quantity of data that is transmitted per second. The symbol rate is
measured in MSymbols/s and is equal to the number of symbols received per second.
Video-Bit-Rate
The video bit rate describes the quantity of data from the digitised video signal that is transmitted per
second.
Viterbi rate
The Viterbi rate (code rate, error rate) characterises the error protection used by the programme provider.
The DVB standard provides the following values: 1/2 - 2/3 - 3/4 - 5/6 - 7/8
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