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How Does DIRECTV Satellite TV Work?
Written by: Rick Taylor - Dec 2, 2008
DIRECTV satellites are placed into a geosynchronous orbit approximately 37,000 km (22,300 miles) above the earth's surface. These satellites always remain above the exact same point on the earth's surface so that all DIRECTV subscriber dishes on the earth's surface at subscribers' homes, offices, restaurants, clubs, etc. are pointed to the same fixed DIRECTV satellite location.
DIRECTV shows, movies, music, pay-per-view, events, etc. are broadcast from an "uplink center" on the earth's surface where programming from cable television networks, local TV stations,and other entertainment broadcast networks is collected and encrypted so that the programming cannot be viewed by non-DIRECTV satellite dish owners. The DIRECTV satellite uplink facility uses large satellite dishes that are 9 to 12 meters wide to transmit a high-strength signal to the orbiting DIRECTV satellite.
Upon receiving the signal containing entertainment programs from the "uplink center," the DIRECTV satellite converts the microsave signal to a different microwave frequency band to ensure that the downlink to the DIRECTV subscribers dishes are not affected by uplink interference.
After traveling more than 50,000 miles, the DIRECTV signal will reach a DIRECTV subscriber's dish located on the outside of the subscriber's home, office, or facility. The signal received from the DIRECTV satellite is focussed by a bowl-shaped parabolic dish onto a device in the center of the dish called a "feed horn." The "feed horn" channels the DIRECTV satellite microwave signal to a "low-noise block downconverter" (LNB). The LNB again filters out unwanted interference, and sometimes converts it to another frequency at the subscriber's location before amplifying the signal and sending it via coaxial cable to the satellite receiver box located inside the DIRECTV subscriber's house, office, or facility.
A DIRECTV satellite receiver box converts the signal to television, audio, High Definition (HD) and/or data signals and may be may be equipped to decrypt the coded signal itself. Subscribers may be supplied with a "smart card" as well to decode the signal.
DIRECTV receivers also include integrated digital video recorders (DVRs) that allow subscribers to rewind and pause live television and to record and store shows on a built-in hard drive. In addition, DIRECTV receivers offer high-definition television (HDTV), pay-per-view events and movies, interactive television channels, and video-on-demand (VOD) channels. |