Kathrein UFD 570/S manual Glossary of Technical Terms, DVB MPEG-2

Glossary of Technical Terms

DVB MPEG-2

DVB is the abbreviation for digital video broadcasting. DVB-T refers to the type of transmission (T = terrestrial). MPEG is the abbreviation for Moving Picture Experts Group, a working group which draws up internationally valid standards for the digital compression of video together with audio. MPEG-2 has been promoted to the standard for the compression of digital TV signals. MPEG-2 operates at a data rate of up to 100 MBit/s.

Eb/No ratio

The Eb/No ratio is a measure for the signal-to-noise ratio of the digital signal. This value is not identical to the C/N value as known from analogue reception technology. As a rule, reception is no longer possible at Eb/No levels below 5 dB.

FEC

FEC is the abbreviation for Forward Error Correction. The FEC error rate corresponds to the viterbirate.

PID

The PID number (Package IDentification) is an identification number for video signals and audio signals in the digital data stream of DVB MPEG-2 signals. The receiver uses the PID number to establish distinct allocation of the video and audio data transmission. PID-PCR is the identification number for the synchronisation signal. PID-PCR is the identification number for the synchronisation signal. PID-PCR is normally identical to PID video. In the case of multi-language channel transmissions, by means of manual entry of the audio PID, it is possible to allocate another language to the TV broadcast. After entering the PID, the digital receiver automatically selects audio data from the data stream identified by the PID number and allocates these data to the video signal.

Channel package

The channel package of a digital transponder mostly contains several TV and radio channels. Each channel package has a fixed allocation with regard to the transponder transmit frequency, the polarization (horizontal or vertical), the symbol rate and the viterbirate or error rate.

Symbol rate

The symbol rate describes the amount of data transmitted per second. The symbol rate is measured in MSymbols/s and is equal to the number of symbols that are received per second.

Video bit rate

The video bit rate describes the quantity of data of the digitised video signal that is transmitted per second.

Viterbi rate

The viterbi rate (code rate, error rate) characterizes the type of error protection used by the channel provider. The DVB standard stipulates the following values: 1/2 - 2/3 - 3/4 - 5/6 - 7/8.

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