Kathrein UFS 640si, Руководство по эксплуатации

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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
SHORT TECHNICAL GUIDE
TRANSPONDER
A transponder is a frequency converter which receives TV and radio signals broadcast from the earth,
converts them and the rebroadcasts them to the earth at a different frequency. Each satellite carries
several transponders.
Analogue transponders transmit only one TV channel and possibly multiple radio channels on a single
transmission frequency.
Digital transponders simultaneously transmit several TV and several radio programmes on a 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.
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
synchronisation 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.