This paper presents an overview of the technological challenges faced by the mobile cellular telephone industry in the quest to provide cheaper and more reliable services. Analog first-generation and digital second-generation cellular systems used in Europe, Japan and the United States are discussed. These systems are designed to support voice communication with limited data communication capabilities. Future systems are targeted to offer a wide variety of services such as telephony, teleconferencing, voice mail, video conferencing, telefax, voiceband data, database access, message broadcasting, remote terminals, and navigation. Wireless subscribers will expect a quality of service similar to that provided by the wireline ISDN network. Service providers will need higher-complexity protocols in the physical layer because of the unpredictable nature of the radio propagation environment and the inherent terminal mobility in a wireless network. These protocols will use powerful error correction and digital speech interpolation techniques to match the quality of service of the fixed wireline network.
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