Television transmitted by the means of communications satellite is called Satellite TV. On ground, the signal is received by a satellite dish and set-top receiver box. Satellite TV caters for a wide range of channels and services.

A transmitting antenna located at an uplink facility forms the foundation of satellite TV. Up-link satellite dishes are huge, as much as 9 to 12 meters (30 to 40 feet) in diameter. The large diameter leads to more precise aiming and improved signal strength at the satellite. The dish used for uplink is pointed towards a specific satellite. To ensure that uplink signals are received by one of the transponders tuned to a specialized frequency spectrum aboard the satellite, the uplink signals are transmitted within the same frequency spectrum. To avoid interference with the up-link signal, the transponder resends the signals back to Earth but in a different frequency spectrum. The resending typically happens in the C-band (4–8 GHz) or Ku-band (12–18 GHz) or sometimes both. The portion of the signal course from the satellite to the receiving Earth station is called the downlink.

The downlinked satellite signal becomes rather feeble after traveling the great distance to Earth. A parabolic receiving dish collects the weak signal and reflects it to the dish’s focal point. Mounted on brackets at the dish's focal point is a device called a feedhorn. This feedhorn is basically the flared front-end of a section of waveguide that gathers the signals at or near the focal point and conducts them to a probe connected to a low-noise block downconverter or LNB. The chunk of frequencies in which the satellite TV signals are transmitted is filtered and amplified by the LNB. The chunk of frequencies is then converted to a lower frequency range in the L-band range by the LNB. Direct broadcast satellite dishes are fitted with an LNBF which integrates the feedhorn with the LNB.

The satellite receiver set-top box then demodulates and converts the signals to the desired form of output for TV, audio, data, etc. The receiver is called an integrated receiver/decoder if the receiver includes the ability to unscramble or decrypt. The cable connecting the receiver to the LNBF or LNB must be of the low loss type RG-6, quad shield RG-6 or RG-11, etc. It cannot be standard RG-59.

The main benefit of satellite television is that providers (like Dish Network or DirecTv) don’t have to lay miles upon miles of cable to deliver television programs to you. They don’t require broadcast centers in every city which duplicates equipment. This saves you money because satellite TV is less expensive to maintain and up-grade, no re-laying of cable to up-grade services is needed. If the primary uplink center has a problem, the secondary uplink center automatically takes over broadcasting. That’s why satellite TV has a less than 1% outage rate. Satellite TV companies rate significantly higher in customer satisfaction than cable television companies.

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