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Introduction to satellite communications

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HISTORY OF SATELLITE COMMUNICATIONS The first artificial satellite was placed in orbit by the Russians in 1957. That satellite, called Sputnik, signaled the beginning of an era. The United States, who was behind the Russians, made an all-out effort to catch up, and launched Score in 1958. That was the first satellite with the primary purpose of communications. The first regular satellite communications service was used by the Navy in 1960. The moon was used to bounce teletypewriter signals between Hawaii and Washington, D.C. During the early 1960s, the Navy used the moon as a medium for passing messages between ships at sea and shore stations. This method of communications proved reliable when other methods failed. Military satellite communications technology was at a low level until 1965. At that time high quality voice transmissions were conducted between a satellite and two earth stations. That was the stepping stone to the Initial Defense Communications Satellite Program (IDCSP), w...

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Electronic Marketing (e-commerce)

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Earn money with AlertPay Electronic commerce, commonly known as (electronic marketing) e-commerce or eCommerce, consists of the buying and selling of products or services over electronic systems such as the Internet and other computer networks. The amount of trade conducted electronically has grown extraordinarily with widespread Internet usage. The use of commerce is conducted in this way, spurring and drawing on innovations in electronic funds transfer, supply chain management, Internet marketing, online transaction processing, electronic data interchange (EDI), inventory management systems, and automated data collection systems. Modern electronic commerce typically uses the World Wide Web at least at some point in the transaction's lifecycle, although it can encompass a wider range of technologies such as e-mail as well. A large percentage of electronic commerce is conducted entirely electronically for virtual items such as access to premium content on a website, but most electr...