Three generations of cellular wireless systems - IEEE Potentials
نویسندگان
چکیده
wireless technology has undergone enormous growth. Surveys have shown that a new wireless subscriber signs up every 2.5 seconds. The number of cellular and personal communication system (PCS) users in the US has surpassed 100 million. However, wireless is not a recent technology. As early as 1793, wireless messages were transmitted in France using the optical telegraph. Stations consisting of a telescope and a set of semaphore flags capable of encoding multiple messages were placed on adjacent hills. France was entirely linked by 566 such
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