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)
“Today so much rebellion is aimless and demoralizing precisely because children have no values to challenge. Teenage rebellion is a testing process in which young people try out various values in order to make them their own. But during those years of trial, error, embarrassment, a child needs family standards to fall back on, reliable habits of thought and feeling that provide security and protection.”
—Neil Kurshan (20th century)
“In this nation I see tens of millions of its citizens, a substantial part of its whole population, who at this very moment are denied the greater part of what the very lowest standards of today call the necessities of life. I see one third of a nation ill-housed, ill-clad, ill-nourished. The test of our progress is not whether we add more to the abundance of those who have much, it is whether we provide enough for those who have too little.”
—Franklin D. Roosevelt (1882–1945)