Standards
Analog television distributed via satellite is usually sent scrambled or unscrambled in NTSC, PAL, or SECAM television broadcast standards. The analog signal is frequency modulated and is converted from an FM signal to what is referred to as baseband. This baseband comprises the video signal and the audio subcarrier(s). The audio subcarrier is further demodulated to provide a raw audio signal.
If the signal is a digitized television signal or multiplex of signals, it is typically QPSK.
In general, digital television, including that transmitted via satellites, are generally based on open standards such as MPEG and DVB-S or ISDB-S.
The conditional access encryption/scrambling methods include NDS, BISS, Conax, Digicipher, Irdeto, Cryptoworks, DG Crypt, Beta digital, SECA Mediaguard, Logiways, Nagravision, PowerVu, Viaccess, Videocipher, and VideoGuard. Many conditional access systems have been compromised.
Read more about this topic: Satellite Television
Famous quotes containing the word standards:
“As long as our people quote English standards they dwarf their own proportions.”
—Ralph Waldo Emerson (1803–1882)
“The home is a woman’s natural background.... From the beginning I tried to have the policy of the store reflect as nearly as it was possible in the commercial world, those standards of comfort and grace which are apparent in a lovely home.”
—Hortense Odlum (1892–?)
“The technologist was the final guise of the white missionary, industrialization the last gospel of a dying race and living standards a substitute for a purpose in living.”
—Max Frisch (1911–1991)