Digital Satellite System is the initialism expansion of the DSS digital

satellite television Satellite television is a service that delivers television programming to viewers by relaying it from a communications satellite orbiting the Earth directly to the viewer's location. The signals are received via an outdoor parabolic antenna commo ...

transmission system used by

DirecTV DirecTV (trademarked as DIRECTV) is an American Multichannel television in the United States, multichannel video programming distributor based in El Segundo, California, El Segundo, California. Originally launched on June 17, 1994, its primary ...

. Only when digital transmission was introduced did

direct broadcast satellite Satellite television is a service that delivers television programming to viewers by relaying it from a communications satellite orbiting the Earth directly to the viewer's location. The signals are received via an outdoor parabolic antenna commo ...

(DBS) television become popular in North America, which has led to both DBS and DSS being used interchangeably to refer to all three commonplace digital transmission formats - DSS, DVB-S and

4DTV 4DTV is a proprietary broadcasting standard and technology for digital cable broadcasting and C-band/Ku-band satellite dishes from Motorola, using General Instrument's DigiCipher II for encryption. It can tune in both analog VideoCipher 2 and dig ...

. Analog DBS services, however, existed prior to DirecTV and were still operational in continental Europe until April 2012. At the time of DirecTV's launch in 1994, the

DVB-S Digital Video Broadcasting – Satellite (DVB-S) is the original DVB standard for Satellite Television and dates from 1995, in its first release, while development lasted from 1993 to 1997. The first commercial applications was by Star TV in Asia ...

digital satellite system in use in the majority of the world had not yet been standardised, the Thomson developed DSS system was used instead. While functionally similar in DVB-S – MPEG 2 video,

MPEG-1 Layer II MPEG-1 Audio Layer II or MPEG-2 Audio Layer II (MP2, sometimes incorrectly called Musicam or MUSICAM) is a lossy audio compression format defined by ISO/IEC 11172-3 alongside MPEG-1 Audio Layer I and MPEG-1 Audio Layer III (MP3). While MP3 i ...

or AC3 audio, QPSK modulation, and identical error correction ( Reed–Solomon coding and Viterbi

forward error correction In computing, telecommunication, information theory, and coding theory, an error correction code, sometimes error correcting code, (ECC) is used for controlling errors in data over unreliable or noisy communication channels. The central idea is ...

), the transport stream and information tables are entirely different from those of DVB. Also unlike DVB, all DSS receivers are proprietary DirecTV reception units. DirecTV is now using a modified version of DVB-S2, the latest version of the DVB-S protocol, for

HDTV High-definition television (HD or HDTV) describes a television system which provides a substantially higher image resolution than the previous generation of technologies. The term has been used since 1936; in more recent times, it refers to the ...

services off the SPACEWAY-1,

SPACEWAY-2 Spaceway-2 is part of DirecTV's constellation of direct broadcast satellites. The satellite was launched via an Arianespace Ariane 5, Ariane 5 ECA rocket from Kourou, French Guiana on 16 November 2005. Its operational position is in geosynchron ...

, DirecTV-10 and DirecTV-11{{Cite web , url=http://dtv.client.shareholder.com/releasedetail.cfm?ReleaseID=324646 , title=The DIRECTV Group, Inc. - DIRECTV Remains Clear HD Leader with 130 HD Channels on Tap for Mid-August , access-date=2008-08-03 , archive-url=https://web.archive.org/web/20080805052202/http://dtv.client.shareholder.com/releasedetail.cfm?ReleaseID=324646 , archive-date=2008-08-05 , url-status=dead satellites; however, huge numbers of DSS encoded channels still remain. The ACM modulation scheme used by DirecTV prevents regular DVB-S2 demodulators from receiving the signal although the data carried are regular MPEG-4 transport streams.

References

External links

DSS, the "Other Other" MPEG-2 system
Satellite television Digital television

See also

References

External links