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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.
TRANSPONDER
A transponder is a frequency converter which receives TV and radio signals broadcast from the earth,
converts them and then rebroadcasts them to the earth at a different frequency. A satellite carries several
transponders.
Analogue transponders transmit only one TV channel and possibly multiple radio channels on a single
transmission frequency.
Digital transponders transmit several TV and several radio programmes simultaneously on a single
transmission frequency. If a programme provider is broadcasting several TV channels via a digital
transponder, we refer to the provider's channel package. The terms “digital transponder” and “channel
package” have the same meaning.
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) characterizes 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
SHORT TECHNICAL GUIDE
