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The author is not mentioned, Wireless, English for communication students, T.V.Kojevnikova, 2012, pp. 217-220.

Wireless.

The aim of the article is to show the reader the progression of wireless communication and its improvement over time.

The research method is description.

The author describes the first commercially available radio and telephone system called IMTS and admits that it was no sophisticated enough to satisfy ever-growing needs of subscribers.

Solution to this problem came in a form of cellular radio, which utilized division of metropolitan areas into cells of few miles in diameter with a transmitter that operated on a particular set of frequencies. Adjacent cells could not use the same set.

The author states that control of handoff and ability to locate subscriber in each of the cell proved cellular radio useful. There are at least three schemes for communication between a vehicle and the cell site: FDMA that was called GSM in Europe, TDMA and CDMA.

The author also describes two satellite systems that provide wireless communications. Geosynchronous satellites are excellent for transmitting data, but have too high of a delay to be useful for voice communications. Low earth orbit satellite systems have low delay but frequently need to hand off a call to another satellite because of their high orbiting speed.

The article describes the period between late 1940s and late 1980s.

The author’s conclusion is that new and more advanced systems were being developed to improve the quality of wireless communications.