TAILIEUCHUNG - GSM and UMTS (P12)

From Analogue Car Telephone to Digital Pocket Phone CEPT took a very much forward looking decision when it decided to create, as early as 1982, the GSM Group with the mandate to define a second generation harmonised cellular system in Europe. At that time, the true market potential for mobile systems was not known. Also many technologies, which became key to the GSM radio design, were just emerging. This is true particularly of cellular networking, digital signal processing and real-time computing. | GSM and UMTS The Creation of Global Mobile Communication Edited by Friedhelm Hillebrand Copyright 2001 John Wiley Sons Ltd ISBNs 0-470-84322-5 Hardback 0-470-845546 Electronic Chapter 12 Radio Aspects Section 1 The Early Years from 1982 to 1995 Didier Verhulst1 From Analogue Car Telephone to Digital Pocket Phone CEPT took a very much forward looking decision when it decided to create as early as 1982 the GSM Group with the mandate to define a second generation harmonised cellular system in Europe. At that time the true market potential for mobile systems was not known. Also many technologies which became key to the GSM radio design were just emerging. This is true particularly of cellular networking digital signal processing and real-time computing. In fact GSM work started when the telecom industry was experiencing a fundamental shift between the circuit switched analogue world and the packet switched digital world. Microprocessors had just been introduced a few years before and it was the time when the first PC was created. The PTT administrations were introducing digital switches in their telephone network to replace mechanical switches and they were developing their first packet switched data networks. We know today that this digital revolution ultimately lead to the Internet as we know it today but this was not at all clear at the time. As we shall see even the decision to select a digital rather than analogue modulation was not obvious and it took almost 5 years to be settled This technological turning point was also a wonderful opportunity for a young generation of engineers who had just learned in school the beauty of digital transmission and packet switching and had therefore the opportunity to contribute actively to the creation of a new standard. Marketing Requirements In the early 1980s the market for a second generation cellular system was perceived as primarily radiotelephone in vehicle. In a study called Future mobile Communication .

• Kĩ thuật Viễn thông
• Didier Verhulst
• GMS
• UMTS
• thông tin toàn cầu
• thông tin di động
• hệ thống GSM
• hệ thống uMTS
• Hệ thống thông tin di động
• Thông tin di động thế hệ ba UMTS
• Công suất trong hệ thống di động
• Kỹ thuật viễn thông
• Công nghệ WCDMA
• Đồ án tốt nghiệp đại học
• Quy hoạch mạng 3G cho Viêng Chăn
• Phương pháp quy hoạch mạng UMTS
• Quy hoạch mạng UMTS
• Enterprise of telecommunication Lao
• Friedhelm Hillebrand
• Thomas haug
• Philippe Dupuis
• Don Zelmer
• the European Research
• Karl Heinz Rosenbrock
• Michel Mouly
• Klaus Vesder
• voice codecs
• Gisela Hertel
• bernard Mallinder
• Ansgar Bergmann
• Renzo Failli
• Friedhelm
• giao diện vô tuyến
• luận văn
• hệ thống điện
• kỹ thuật điện
• tóm tắt luận văn