This paper presents an overview of the technological challengesfaced by the mobile cellular telephone industry in the quest to providecheaper and more reliable services. Analog first-generation and digitalsecond-generation cellular systems used in Europe, Japan and the UnitedStates are discussed. These systems are designed to support voicecommunication with limited data communication capabilities. Futuresystems are targeted to offer a wide variety of services such astelephony, teleconferencing, voice mail, video conferencing, telefax,voiceband data, database access, message broadcasting, remote terminals,and navigation. Wireless subscribers will expect a quality of servicesimilar to that provided by the wireline ISDN network. Service providerswill need higher-complexity protocols in the physical layer because ofthe unpredictable nature of the radio propagation environment and theinherent terminal mobility in a wireless network. These protocols willuse powerful error correction and digital speech interpolationtechniques to match the quality of service of the fixed wireline network
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