Brief Technical Glossary
Programme package
The programme package for a digital transponder normally includes several TV and radio programmes. Each programme package has a fi xed assignment for the transponder transmission frequency, for polarisation (horizontal or vertical), for the symbol rate and for the Viterbi rate or error rate.
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 satellite transmitter, which transmits TV and radio signals. A satellite has several transponders.
Analogue transponders transmit only one TV programme and possibly several radio programmes at the transmission frequency.
Digital transponders simultaneously transmit several TV and several radio programmes at a transmission frequency. If a programme provider is broadcasting several TV programmes via a digital transponder, we refer to the provider‘s programme package. The terms digital transponder and programme 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) 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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