Digital Video Broadcasting (DVB) is a suite of internationally accepted open standards for digital television. DVB standards are maintained by the DVB Project, an international industry consortium with more than 270 members, and they are published by a Joint Technical Committee (JTC) of European Telecommunications Standards Institute (ETSI), European Committee for Electrotechnical Standardization (CENELEC) and European Broadcasting Union (EBU). The interaction of the DVB sub-standards is described in the DVB Cookbook. Many aspects of DVB are patented, including elements of the MPEG video coding and audio coding
DVB-S is an abbreviation for Digital Video Broadcasting — Satellite; it is the original Digital Video Broadcasting Forward error correction and demodulation standard for Satellite Television and dates from 1994, in its first release, while development lasted from 1993 to 1997. The first application was commercially available in France via Canal+, enabling digitally broadcast, satellite-delivered Television to the public. 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 like Sky (UK & Ireland) via Astra in Europe, Dish Network and Globecast in the U.S. and Bell TV in Canada. 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). Some amateur television repeaters also use this mode in the 1.2 GHz amateur band.
Digital terrestrial television (DTTV or DTT) is the technological evolution of broadcast television and an advancement of analog television. DTTV broadcasts land-based (terrestrial) signals. The purposes of digital terrestrial television, similar to digital versus analog in other platforms such as cable, satellite, and telecommunications, reduced use of spectrum and to provide more capacity than analog, provide better quality picture, and to lower operating costs for broadcast and transmission (after the initial upgrade costs). A terrestrial implementation of digital television (DTV) technology uses an aerial to broadcast to a conventional television antenna (or aerial) instead of a satellite dish or cable television connections.
Competing variants of broadcast television systems are being used around the world. Advanced Television Standards Committee created the ATSC standards that use an ATSC tuner in North America and South Korea—an evolution from the analog National Television Standards Committee (NTSC) standard. Integrated Services Digital Broadcasting (ISDB-T) is used in Japan, with a variation of it being used in most of South America. DVB-T is the most prevalent, covering Europe, Australia, New Zealand, Colombia and some countries of Africa. DMB-T/H is China’s own standard (including Hong Kong, though Hong Kong’s cable operators use DVB); the rest of the world remains mostly undecided, many evaluating multiple standards. ISDB-T is very similar to DVB-T and can share front-end receiver and demodulator components. Several European countries have switched from analog to digital terrestrial television, with the rest hoping to have completed the switchover mostly by 2012.