2010년 6월 18일 금요일

A brief History of Satellite TV

In a relatively short time, satellites have become an essential part of global communication.
And satellite TV may seem quite new, but its history actually spans over a fifty year period. Here is a brief history of broadcasting satellite in the world.

Konstantin Tsiolkovsky theorized many aspects of space travel and rocket propulsion in 1898.
He was an Imperial Russian and Soviet rocket scientist and pioneer of the astronautic theory.
He is considered by many to be the father of spaceflight.










The original concept of satellite television is often attributed to writer Arthur C. Clarke who was the first to suggest a worldwide satellite communications system.
But the notion of a geosynchronous satellite for communication purposes was first published in 1928 (but not widely so) by Herman Potočnik.
The idea of a geostationary orbit was first published on a wide scale in a paper entitled "Extra-Terrestrial Relays — Can Rocket Stations Give Worldwide Radio Coverage?" by Arthur C. Clarke, published in Wireless World magazine in 1945. In this paper, Clarke was the first to describe it as a useful orbit for communications satellites for broadcast and relay purposes.
As a result this is sometimes referred to as the Clarke Orbit or Clarke Belt.(Arthur Charles Clarke was a British science fiction author, inventor, and futurist)

It was impossible to carry out an artificial satellites to out of the earth at that time.
It needed a good rocket which has a powerful propulsion.
But the rocket technology is low to do it.
During the World War I & II, the rocket technology had developed because the military need a good weapons like a missile.

Sputnik 1, the first artificial satellites in the world, was launched by Soviet Union.
That launch took place on October 4, 1957
.It was the first human-made object to orbit the Earth.
The Russian word sputnik literally means "traveling companion".
Monitoring of the satellite was done by many amateur radio operators.
Sputnik 1 was not visible from Earth but the casing of the R-7 booster, traveling behind it, was.






The surprise launch of Sputnik 1 shocked the United States.
The Sputnik crisis also led to the creation of NASA,
and an increase in U.S. government spending on scientific research and education.
Explorer 1 was the first Earth satellite of the United States as part of the program for the International Geophysical Year
and in response to the launch of the Soviet satellite Sputnik 1.
Launched on 31 January 1958 at 03:48 UTC atop the first Juno booster from LC-26
at Cape Canaveral Air Force Station, Florida. It was the first spacecraft to recognize the Van Allen radiation belt.
In 1960, the first communication satellite, named Echo, was launched.
It was basically not much more than a reflector, which reflected the TV signals from earth.
Project Echo was NASA's first passive communications satellite experiment. Each spacecraft was designed as a metalized balloon satellite acting as a passive reflector of microwave signals.Communication signals were bounced off of them from one point on Earth to another.
On July 10, 1962 Telstar, the first first active TV satellite, was launched.
It was experimental, Telstar 1 relayed the first television pictures, telephone calls and fax images
through space and provided the first live transatlantic television feed.
It also converted the signals to avoid interference between the incoming and outgoing signals.
Telstar had a rotational speed which was different from the rotational velocity of the earth,
so it needed a satellite tracking system at both transmission and reception stations.

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On February 14, 1963 , Syncom 1 was launched.
Syncom 1 was to be the first geosynchronous communications satellite.
It was launched with the Delta B #16 launch vehicle from Cape Canaveral,
but was lost on the way to geosynchronous orbit due to an electronics failure.

Syncom 2 was the first geosynchronous communication satellite. Its orbit was inclined rather than geostationary.
The satellite was launched by NASA on July 26, 1963. The satellite successfully kept station at the altitude calculated
by Herman Potočnik Noordung in the 1920s. During the first year of Syncom 2 operations, NASA conducted voice,
teletype, and facsimile tests, as well as 110 public demonstrations to show the capabilities of this satellite
and invite feedback. In August 1963, President John F. Kennedy in Washington, D.C., telephoned Nigerian Prime Minister
Abubakar Balewa aboard USNS Kingsport docked in Lagos Harbor; the first live two-way call between heads of government
by satellite. The Kingsport acted as a control station and uplink station. Syncom 2 also relayed a number of test television
transmissions from Ft. Dix, N.J. to a ground station in Andover, Maine beginning on Sept. 29, 1963; the first successful TV
transmission through a geosynchronous satellite. It was low-quality video with no audio.

Syncom 3 was the first geostationary communication satellite, launched on August 19, 1964
and was used to telecast the 1964 Summer Olympics in Tokyo to the United States.
Although Syncom 3 is some times credited with the first television program to cross the Pacific Ocean

Many others have followed since. The most well known is probably Intelsat I, which was launched in 1965.
It is the first commercial satellite for communication purpose in the world.
By 1969 the satellite net had expanded to a worldwide communication and TV network.

In December 1982, the Astra I satellite was launched, which generated new interest in satellites f
rom the general public in Europe. With its coming it has become possible for people in Europe
to receive TV and radio transmissions with a small dish antenna.( DTH, Direct To Home)


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August 11 1992, KITSAT 1(Uribyol 1), the first artificial satellites of the Korea,
was launched from Guiana Kourou space center.
August 5 1995, Koreasat 1 (Mugunghwa 1), the first commercial satellite for communication purpose,
was launched at Cape Canaveral Air Force Station Florida in US.

Janury 14 1996, Koreasat 2 (Mugunghwa 2), was launched.
July 1 1996 at 10:00 am, KBS sent first testing signal for satellite broadcasting via the Koreasat 2.

September 5 1999, ABS 7 ,old Koreasat 3 (Mugunghwa 3), was launched.
March 1, 2002 Skylife which is a satellite broadcasting provider of South Korea,
Officially opened the satellite broadcasting service.


March 2004, Hanbyol 1 was launched.January 2005, TU Media started the satellite DMB service.
There are more than 30 Free To Air TV channels for poor reception area in Korea (via ABS 7 & Koreasat 5.)
So, anyone can legally receive FTA channels by using FTA satellite receiver without subscription.(free of charge)
Satellite boradcasting is the digitlal format so deliver the clearest images to the viewer,
really good quality video & audio, much better than analog and provide several hundred channels from which to choose.
People can use both digital TV and analoge TV to watch.


Written by Martin Shin.

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