Guest Post by Philip J Reed on behalf of WildBlue
Satellites help form the foundation of the global telecommunications network comprising telephone, television, and Internet services. They allow anyone in any location to pick up a cell phone and dial somebody across the world or to watch a sports game in another country. Satellites were once believed to be science fiction and outside humanity?s technological prowess, but the past half century has marked dramatic technological advances once thought impossible.
The Start of a Dream
As early as 1945, Arthur C. Clarke wrote about a network of satellites capable of transmitting television signals around the world. However, the idea failed to catch on at first, and Clarke?s articles and stories were considered fanciful until the Soviet Union launched the satellite Sputnik in 1957.
During the height of the Cold War, the Soviet Union showed that orbital satellites were not only theoretically possible but feasible with the current technology of the day. Overnight, news outlets and government agencies around the world began to seriously consider what capabilities they could arm satellites with.
Many initial theories centered around Clarke?s idea of a global communications network, but there were also fears that governments could arm satellites with ballistic missiles or other weapons. While Clarke?s peaceful vision has held true so far, there does not yet exist a comprehensive space weapons ban. However, U.S. President Barack Obama signaled a wish to ban anti-satellite weapons in 2009.
The First Communications Satellites
In 1960, AT&T filed for permission to place a communications satellite in orbit. Two years later, the first active communications website, Telstar-1, began to receive and transmit signals to ground-based dishes.
These satellites were placed into geostationary orbit over the equator. Because they completed one orbit every 24 hours, they were always located directly above the same point on the ground, allowing ground-based satellite dishes to maintain a static angle. Unfortunately, signals from equatorial satellites grow weak at high latitudes, which can prove problematic for regions like northern Canada or southern Chile.
The first communications satellites were capable of only a few dozen simultaneous phone calls. Computer circuits were both primitive and expensive, and the rockets capable of carrying the satellites into orbit cost thousands of dollars per pound for each payload. Given these costs, it?s nothing short of remarkable that AT&T, Comsat, and other early satellite providers were able to quickly and completely recoup their losses, paving the way for an entirely new industry.
Ubiquitous Service
Once telecommunications providers started developing new satellites, the industry made advances on a monthly basis. Today, integrated circuits used in satellites cost a small fraction of the price, but they?re capable of transmitting thousands of simultaneous telephone calls instead of dozens.
Just three years after the launch of Telstar-1, AT&T proposed a satellite TV network for the continental United States, but the proposal was promptly ignored as in the case of Arthur C. Clarke?s 1945 article. It would not be until 1972 that a major telecommunications company, Telesat Canada, would begin providing satellite television service. Western Union launched the first TV satellite for the United States in 1974.
Less than one year later, HBO introduced premium television service to U.S. customers, and high adoption rates spurred further satellite TV development. However, satellite telephone service did not take off until the 1990s, and satellite Internet became popular only after the turn of the century.
Where Does the Future Lead?
Over the past decade, launch services have moved from the public to private sectors. SpaceX, or Space Exploration Technologies Corporation, has built and tested two different rocket designs. The SpaceX Dragon 9 rocket was so innovative that it slashed launch costs by 90 percent, driving launch costs down below $1,000 per pound.
Satellites themselves are also smaller, cheaper, and more powerful than ever before. Cube satellites can measure as little as 1,000 cubic centimeters, about the size of a grapefruit. While cube satellites are used primarily for scientific research, they demonstrate how compressed satellite technology has become.
Because satellites are cheaper to build and launch into orbit than ever before, they will continue to complement land-based telecommunications for the next few decades. Whether or not satellite communications can sustain growth with limited frequencies and bandwidth remains to be seen.
For further reading?
http://history.nasa.gov/satcomhistory.html
http://www.nss.org/articles/falconheavy.html
http://www.reuters.com/article/2009/01/25/us-usa-obama-space-idUSTRE50O15X20090125
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Source: http://rashidfaridi.wordpress.com/2012/10/25/the-history-and-future-of-satellite-communications/
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