History of Satellite Communications

In 1945 the first idea of ​​historical satellite communications for satellite communications came from an article entitled "Wireless World", where the author C. Distribution of a manned satellite I mentioned the use. However, the first person who carefully assessed the technical and financial aspects of such a company was John R. Pierce (Whalen, n.d) of Bell Telephone Laboratories. In a speech in 1954 and an article in 1955, Pierce explained the usefulness of "mirror" in communication in space, mid-track "repeater", and 24-hour track "repeater". When comparing satellite communication capacity, he estimated the capacity of 1,000 simultaneous phones.

The history of satellite communications dates back to 1945. A paper entitled "Overseas Relay" was written by Arthur C. Clarke and first described about the principles of satellite and geosynchronous satellite communications 25 years later. One speculative space era began in 1957, with the launch of the first satellite, Soviet SPUTNIK. In the next year there were various experiments including the world's first satellite ECHO (1960) reflecting the United States, the European power relay satellite TELSTAR (1962), and NASA's first geostationary satellite SYNCOM. (1963) and the world's first commercial geostationary satellite INTELSAT I or American Early Birds (1965)

Communication satellites are satellites that exist in the universe for telecommunications. Modern communications satellites use various orbits, including geosynchronous orbit, Molina orbit, other elliptical orbits, and low Earth orbits. For fixed services, communication satellites provide microwave wireless relay technology complementing submarine communication cables. They are also used for television and radio broadcasting where mobile applications such as communications with ships, vehicles, airplanes and mobile terminals and other technologies such as cable and television are impractical or impossible .

Communication satellites - satellites communicate via microwave radio waves that are not affected by the Earth 's atmosphere. These satellites are usually placed on a stationary orbit of 35,400 km (22,000 miles) on the equator. These earth orbit systems can receive and transfer voice, data and television signals. Wireless and spread spectrum technology - Wireless LAN uses high frequency wireless technology similar to digital cellular and low frequency wireless technology. Wireless LAN uses spread spectrum technology to enable communication between multiple devices within a limited area. IEEE 802.11 defines an open standard radio technology of a common style called Wi-Fi.

Communication between radio stations dedicated to the earth (earth stations) by radio stations installed in the spacecraft (space station) is called "satellite communication". Satellite communication has achieved various objectives such as weather, radio, internet, television. Therefore, in this research, we focus only on satellite communication for television broadcasting which transmits and receives signals via communication satellite (abbreviated as COMSAT), that is, artificial satellites placed in outer space for telecommunication purposes.