Overall System and programming of Satellite TV

Early Satellite TV viewers was like the explorers. Their dish and receiver let them pick up foreign stations, live feeds between different broadcast stations, NASA activities and other broadcast sources via satellites. The dishes were expensive to discover unique programming that wasn't really intended for mass audiences.

Some satellite owners still try to look for those unauthorized programming on their own, but today, most satellite TV customers get their programming channels through a direct broadcast satellite (DBS) provider, such as DirecTV or the Dish Network. The provider consist of a huge number of pramming channels and broadcasts them to subscribers in different package. Basically, the provider entertain the subscriber by bringing hundreds of channels to their television which can competie, cable TV. Different with earlier programming, the provider's broadcast is absolutely digital, which means it has much better picture and sound quality. Early satellite television was broadcast in C-band radio -- radio in the 3.4-gigahertz (GHz) to 7-GHz frequency range. Digital broadcast satellite transmits programming in the Ku frequency range (12 GHz to 14 GHz ).

There are five major components involved in a direct to home (DTH) satellite system: the programming source, the broadcast center, the satellite, satellite dish and the receiver.

Satellite TV providers get programming from two major sources: national turnaround channels (such as HBO, ESPN and CNN) and various local channels (the NBC, CBS, ABC, PBS and Fox affiliates in a particular area). Most of the turnaround channels also provide programming for cable television, and the local channels typically broadcast their programming over the airwaves.

Turnaround channels usually have braodcast center that transmit their programming to a geostationary satellite. The broadcast center uses plenty of large satellite dishes to radiowave signals from several sources.

Most local stations don't use satellite system. If the provider includes local programming in a particular area, it will have a small ground communications equipment. The equipment receives local signals directly from the broadcaster through fiber-optic cable or antenna and then transmits them to the central broadcast center.

The broadcast center converts all of this programming into a high-quality, uncompressed digital stream. At this point, the centre gather a quantity of data -- about 270 megabits per second (Mbps) for each channel. In order to transmit all channels' signal in an effectively way, the broadcast center has to compress it. Otherwise, it cannot broadcast so many channels with the constraint of Satellite System.