Satellite television
Satellite television is a service that delivers television
programming to viewers by relaying it from a
communications satellite orbiting the Earth directly to the viewer's location. The
signals are received via an outdoor
parabolic antenna commonly referred to as a
satellite dish and a
low-noise block downconverter.
A satellite receiver then
decodes the desired television programme for viewing on a
television set. Receivers can be external
set-top boxes, or a built-in
television tuner. Satellite television provides a wide range of channels and services. It is usually the only television available in many remote geographic areas without
terrestrial television or
cable television service.
Modern systems signals are relayed from a communications satellite on the
Ku band frequencies (12–18
GHz) requiring only a small dish less than a meter in
diameter. The first satellite TV systems were an obsolete type now known as
television receive-only. These systems received weaker analog signals transmitted in the
C-band (4–8 GHz) from
FSS type satellites, requiring the use of large 2–3-meter dishes. Consequently, these systems were nicknamed "big dish" systems, and were more expensive and less popular.
Early systems used
analog signals, but modern ones use
digital signals which allow transmission of the modern television standard
high-definition television, due to the significantly improved
spectral efficiency of digital broadcasting. As of 2018,
Star One C2 from Brazil is the only remaining satellite broadcasting in analog signals, as well as one channel (
C-SPAN) on
AMC-11 from the United States.
Different receivers are required for the two types. Some transmissions and channels are unencrypted and therefore
free-to-air or
free-to-view, while many other channels are transmitted with encryption (
pay television), requiring the viewer to subscribe and pay a monthly fee to receive the programming.
Satellite TV is being affected by the
cord-cutting trend where people are shifting towards internet based
streaming television.
Freesat
Freesat is a British free-to-air satellite television service, provided by joint venture between the BBC and
ITV plc. The service was formed as a
memorandum in 2007 and has been marketed since 6 May 2008. Freesat offers a satellite alternative to the
Freeview service on
digital terrestrial television, with a broadly similar selection of channels available without subscription for users purchasing a receiver.
The service also makes use of the additional capacity available on satellite broadcasting to offer a selection of 17 (as of October 2018) high-definition channels from the BBC, ITV, Channel 5, Arirang TV, Bloomberg, Daystar, Discovery Networks, France 24, NHK, RT UK and TRT World.
Freesat's main competitors are Freeview, Freesat from Sky, Virgin Media and BT. TalkTalk also offer a YouView service (with Channel 4HD and All 4 catch up).
