TAILIEUCHUNG - Wireless địa phương vòng - lý thuyết và ứng dụng P3

The provision of wireless access to the Public Switched Telephone Network (PSTN) from a customer premises is known as Wireless Local Loop (WLL). The potential markets of application of WLL range from developing countries to developed ones. In both cases, the liberalization of the telecommunications market has allowed competition among operators around the world. Many communities of difficult access are still waiting for basic telephone service, which could be viable only by wireless technology, which, besides, offers a fast and cost-effective option | Wireless Local Loops Theory and Applications Peter Stavroulakis Copyright 2001 John Wiley Sons Ltd ISBNs 0-471-49846-7 Hardback 0-470-84187-7 Electronic 3 Wireless Local Loop Networks Capacity Enhancement by Space Division Multiple Access Giselle M. Galvan-Tejada and John G. Gardiner Introduction The provision of wireless access to the Public Switched Telephone Network PSTN from a customer premises is known as Wireless Local Loop WLL . The potential markets of application of WLL range from developing countries to developed ones. In both cases the liberalization of the telecommunications market has allowed competition among operators around the world. Many communities of difficult access are still waiting for basic telephone service which could be viable only by wireless technology which besides offers a fast and cost-effective option. However as all wireless systems WLL must face the task of employing efficiently the scarce radio frequency spectrum within a services demanding market. This is translated into the need for a multiple access technique capable to provide a capacity as large as possible. Space Division Multiple Access SDMA is being widely considered as a mechanism to achieve this aim. SDMA is supported on the use of an adaptive antenna array at base stations. Based on SDMA principles an antenna array at WLL customer premises is proposed here in order to get an additional improvement in the system capacity. Background Definition of Wireless Local Loop and General Aspects Why Wireless in the Local Loop The classical telephone network Public Switch Telephone Network PSTN consists of user terminals and switching centres or exchanges. The user terminals are connected through several exchanges by means of wired links. Usually the end link . between the last exchange and the user has been traditionally implemented with copper wire. This last link is known as the local loop. Thus a wireless local loop will be one that uses the radio .

• Kĩ thuật Viễn thông
• Lý thuyết Wireless
• ứng dụng wireless
• dịch vụ truyền thông
• hạ tầng viễn thông
• vòng lặp không dây
• Bài giảng Lý thuyết mạng máy tính
• Lý thuyết mạng máy tính
• Mạng máy tính
• Wireless và mobile network
• Cellular internet access
• Mạng wireless
• tài liệu MPG
• lý thuyết mạch
• điện tử viễn thông
• tự học viện thông
• lý thuyết viễn thông
• Quản trị mạng máy tính
• Mobile network