3.1 Brief History


At the beginning of the 1950s, the Bell telephone company in the United States introduced a radio telephone service for its customers. This was the first instance of a radio telephony network for commercial use. However, this network was small and could accommodate very few subscribers. As the demand for radio telephony service slowly grew, it forced engineers to come up with better ways to use the radio spectrum to enhance capacity and serve more subscribers. In 1964 the concept of shared resources was introduced. This innovation allowed networks to allocate radio resources on a dynamic basis. As a result, more subscribers could be served by the radio networks.

Spectrum for radio telephony was a scarce resource (and still is), and the need to optimize the available resources to increase utilization has always been a driver in radio networks. In 1971 the FCC (Federal Communications Commission) in the United States allocated a frequency band for radio telephony. The Bell telephone company introduced the AMPS (Advanced Mobile Phone Service) radio network, thereby deploying the first cellular network. In 1982 the United States standardized the AMPS system specification, and this became the radio telephony standard for North America.

In the 1980s several cellular radio networks were deployed around the world. In Europe each country chose its own technology for analog cellular telephony. The UK and Italy chose the American system under the name TACS (Total Access Cellular System). The Scandinavian countries and France chose the NMT (Nordic Mobile Telephone) standard. Germany chose the C-Net standard. All these were analog systems and hence considered as first-generation systems.

In 1982 the Conference of European Posts and Telecommunications (CEPT) created the Groupe Special Mobile (now known as GSM) and mandated the creation of a European standard for mobile radio telecommunications in the frequency band reserved for this purpose. This group produced the GSM standard that is widely deployed today. It also introduced digital radio telephony. Hence the second generation of mobile systems was created. In the United States, the Telecommunication Industry Association has developed two interim standards ”the IS-54 standard in 1990, which is based on TDMA, and the IS-95 standard in 1993, which is based on CDMA. The evolution of these networks is covered in Chapter 15.



IP in Wireless Networks
IP in Wireless Networks
ISBN: 0130666483
EAN: 2147483647
Year: 2003
Pages: 164

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