Dvb s s2 c t Tuners

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DVB-S/S2/C/T Tuners

DVB stands for Digital Video Broadcasting and is standard for watching TV. To categorize what the tuner is used for a letter is added. C stands for cable, S stands for satellite and T for Terrestrial.


DVB-S and Second Generation (DVB-S2)

DVB-S is the original DVB a standard for Satellite Television and dates from 1995. It is used via satellites serving every continent of the world. DVB-S is used in both Multiple Channel Per Carrier (MCPC) and Single channel per carrier modes for Broadcast Network feeds as well as for direct-broadcast satellite services. While the actual DVB-S standard only specifies physical link characteristics and framing, the overlaid transport stream delivered by DVB-S is mandated as MPEG-2, known as MPEG transport stream (MPEG-TS).

DVB-S2 was developed in 2003 and improves upon DVB-S. DVB-S2 is envisaged (contemplate) for broadcast services including standard and HDTV, interactive services including Internet access, and (professional) data content distribution. The development of DVB-S2 coincided with the introduction of HDTV and H.264 (MPEG-4 AVC) video codecs.


DVB-C

This system transmits an MPEG-2 or MPEG-4 family digital audio/digital video stream, using a QAM modulation with channel coding. The standard was first published by the ETSI in 1994, and subsequently became the most widely used transmission system for digital cable television in Europe, Asia and South America. DVB-C2 is an improvement of DVB-C and can handle 4K.


DVB-T

Was first published in 1997 this system transmits compressed digital audio, digital video and other data in an MPEG transport stream, using coded orthogonal frequency-division multiplexing (COFDM or OFDM) modulation. It is also the format widely used worldwide (including North America) for Electronic News Gathering for transmission of video and audio from a mobile newsgathering vehicle to a central receive point.


DVB-S2X

DVB-S2X is an extension of DVB-S2 satellite digital broadcasting standard. DVB-S2X is a digital satellite television broadcast standard. It has been standardized by DVB Project in March 2014 as an optional extension of DVB-S2 standard. It will also become an ETSI standard.

Compared to DVB-S2, efficiency gains up to 51% can be achieved with DVB-S2X.

Amongst improvements are:

  • Higher Modulation Schemes (64/128/256APSK)
  • Smaller Roll-off factors
  • Improved filtering making it possible to have smaller carrier spacing
  • Due to a lack of downward compatibility with existing DVB-S2 decoders, Belgian(?) company Newtec has developed the 'DVB-S2plus/Extensions' technology, which tries to reconcile the benefits of the DVB-S2X with compatibility to existing systems.
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