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Satellite Internet access is Internet access provided through communications satellites. Modern satellite Internet service is typically provided to users through geostationary satellites that can offer high data speeds,〔(【引用サイトリンク】url=http://arstechnica.com/business/2013/01/satellite-internet-15mbps-no-matter-where-you-live-in-the-us/ )〕 with newer satellites using to achieve downstream data speeds up to 50 Mbps.〔(A new breed of broadband satellites could have you living on a desert island ), Network World, 23 July 2014, Patrick Nelson〕 ==History of satellite Internet== Following the launch of the first satellite, Sputnik 1, by the Soviet Union in October, 1957, the US successfully launched the Explorer 1 satellite in 1958. The first commercial communications satellite was Telstar 1, built by Bell Labs and launched in July, 1962. The idea of a Geosynchronous satellite — one that could orbit the Earth above the equator and remain fixed by following the Earth’s rotation — was first proposed by Herman Potočnik in 1928 and popularised by the science fiction author Arthur C. Clarke in a paper in Wireless World in 1945. The first satellite to successfully reach geostationary orbit was Syncom3, built by Hughes Aircraft for NASA and launched Aug. 19, 1963. Succeeding generations of communications satellites featuring larger capacities and improved performance characteristics were adopted for use in television delivery, military applications and telecommunications purposes. Following the invention of the Internet and the World Wide Web, geostationary satellites attracted interest as a potential means of providing Internet access. A significant enabler of satellite-delivered Internet has been the opening up of the for satellites. In December, 1993, Hughes Aircraft Co. filed with the Federal Communications Commission for a license to launch the first Ka-band satellite, Spaceway. In 1995, the FCC issued a call for more Ka-band satellite applications, attracting applications from 15 companies. Among those were EchoStar, Lockheed Martin, GE-Americom, Motorola and KaStar Satellite, which later became WildBlue. Among prominent aspirants in the early-stage satellite Internet sector was Teledesic, an ambitious and ultimately failed project funded in part by Microsoft that ended up costing more than $9 billion. Teledesic's idea was to create a broadband satellite constellation of hundreds of low-orbiting satellites in the Ka-band frequency, providing inexpensive Internet access with download speeds of up to 720 Mbit/s. The project was abandoned in 2003. Teledesic's failure, coupled with the bankruptcy filings of the satellite communications providers Iridium Communications Inc. and Globalstar, dampened marketplace enthusiasm for satellite Internet development. It wasn’t until September 2003 when the first Internet-ready satellite for consumers was launched by Eutelsat. In 2004 with the launch of Anik F2, the first high throughput satellite, a class of next-generation satellites providing improved capacity and bandwidth became operational. More recently, high throughput satellites such as ViaSat's ViaSat-1 satellite in 2011 and HughesNet’s Jupiter in 2012 have achieved further improvements, elevating downstream data rates from 1-3 Mbit/s up to 12-15Mbit/s and beyond. Internet access services tied to these satellites are targeted largely to rural residents as an alternative to Internet service via dial-up, ADSL or classic FSSes. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Satellite Internet access」の詳細全文を読む スポンサード リンク
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