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Điện thoại di động mạng lưới Radio P8

Cordless Telephone Systems Cordless telephone systems are mobile radio systems that, although their transmission range is not suitable for wide-area coverage, are attractive to many users because of the services offered and their low cost. Cordless telephony (CT) can be used within the area of a subscriber line, and provides a radio link within a radius of approximately 50 m inside a building or 300 m outdoors between the fixed terminal and a mobile part. This requires the fixed terminal, as the base station, and the mobile part each to be equipped with transmitting and receiving capabilities. . | Mobile Radio Networks Networking and Protocols. Bernhard H. Walke Copyright 1999 John Wiley Sons Ltd ISBNs 0-471-97595-8 Hardback 0-470-84193-1 Electronic 8 Cordless Telephone Systems Cordless telephone systems are mobile radio systems that although their transmission range is not suitable for wide-area coverage are attractive to many users because of the services offered and their low cost. Cordless telephony CT can be used within the area of a subscriber line and provides a radio link within a radius of approximately 50 m inside a building or 300m outdoors between the fixed terminal and a mobile part. This requires the fixed terminal as the base station and the mobile part each to be equipped with transmitting and receiving capabilities. Along with their suitability for home use a base station a mobile part CT systems lend themselves to other uses Microcellular cordless private branch exchanges e.g. for use in offices and industrial plants. Public cellular systems with local coverage and as regional or nationwide networks for public cordless coin-operated telephones from which calls can be made from appropriate portable terminals without use of previously conventional telephone cells Telepoint service . Wireless access technology for stationary users of telecommunications networks. The first cordless telephones in Europe came from the USA and the Far East. This CTO-designated equipment which was not authorized in the European countries used analogue transmission technology at 1.6 or 4.7 MHz with eight channels each with 25 kHz and because of the lack of security provisions was particularly susceptible to eavesdropping see Table 8.1 . Furthermore the equipment could be used fraudulantly as a telephone handset to access other base stations and their lines. The disadvantages of CT0 equipment led to the development of the CT1 standard for cordless telephony in 1983 under the aegis of CEPT. Two bands with a 2 MHz bandwidth and 45 MHz duplex spacing at 900 MHz were .