Wireless Access Networks: Fixed Wireless Access and WLL Networks -- Design and Operation - Hardcover

Über die Autorin bzw. den Autor

MARTIN CLARK'S 'apprenticeship' included international network planning for British Telecom, managing the global corporate network of Grand Metropolitan, setting up Cable Wireless' pan-European Managed Data Network, managing Deutsche Bank's corporate network and helping to found Mannesmann ARCOR (Germany's second largest public carrier). Recently he has been active in the field of wireless access, assisting a number of start-up carriers across Europe. He is a Chartered European Engineer and member of the IEE.

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Fixed wireless access networks and Wireless Local Loop (WLL) technology are effective and efficient means for rapidly creating new access to telecommunications networks and services which are short of capacity and incapable of handling the bitrates expected by today's high speed multimedia, Internet, video and voice services.

Wireless Access Networks is a complete reference for all involved in fixed wireless access and wireless local loop, including business strategists, marketing, technical, planning and operations staff of public network operators, as well as students.

Well-illustrated and simple-to-read, topics covered include:
* Economics of fixed wireless networks - why and when they are attractive
* Technical and operational planning, practicality and maintenance
* Design of radio systems and their basic functionality
* Point-to-point (PTP) and point-to-multipoint (PMP) radio
* Calculation of radio system range and reliability
* Fixed wireless applications and their network integration

Aus dem Klappentext

Fixed wireless access networks and Wireless Local Loop (WLL) technology are effective and efficient means for rapidly creating new access to telecommunications networks and services which are short of capacity and incapable of handling the bitrates expected by today's high speed multimedia, Internet, video and voice services.

Wireless Access Networks is a complete reference for all involved in fixed wireless access and wireless local loop, including business strategists, marketing, technical, planning and operations staff of public network operators, as well as students.

Well-illustrated and simple-to-read, topics covered include:
* Economics of fixed wireless networks - why and when they are attractive
* Technical and operational planning, practicality and maintenance
* Design of radio systems and their basic functionality
* Point-to-point (PTP) and point-to-multipoint (PMP) radio
* Calculation of radio system range and reliability
* Fixed wireless applications and their network integration

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The Case for Fixed Wireless Networks

Radio

By using a very strong electrical signal as a transmitting source, an electromagnetic wave can be made to spread far and wide through thin air. That is the principle of radio, discovered by Heinrich Hertz in 1887. The radio waves are produced by transmitters, which consist of a radio wave source connected to some form of antenna. Examples of radio systems which are used in public telecommunications or broadcast networks include:

* low frequency radio and mast antenna used in public radio broadcast applications (LW (longwave), MW (medium wave), SW (shortwave));
* HF (High Frequency), VHF (Very HF), or UHF (Ultra-HF) radio system and mast antenna used for modern public radio broadcast, particularly for local radio stations and television broadcasting;
* troposheric scatter radio systems used in early `over-the horizon' telecommunications radio systems, e.g. from ship-to-shore; microwave radio links, providing for point-to-point (PTP) connections between pairs of endpoints, using highly directional dish-type antennas; satellite radio systems, providing for both point-to-point (PTP) as well as point-to multipoint (PMP) and broadcast applications over long distances and very large geographical areas;
* cellular radio systems, used to provide mobile telephone service from portable devices, car telephones and handheld mobile telephones; fixed wireless access networks.

Fixed wireless access systems, the main subject of this book, provide for the `last mile' connection of the customer site or other remote location to the public telecommunications network. Fixed wireless access provides for a real alternative to 'wireline' local loop connections, and thus the common term Wireless Local Loop (WLL).

A subscriber radio unit, or Terminal Station (TS), is installed permanently at a fixed location (e.g. in a customer's premises) and directed at the base station (or Central Station (CS) a site connected to the `backbone' network of the public telecommunications network provider).

Unlike a mobile telephone network, there is usually no scope for motion of a subscriber radio unit of a fixed wireless access system during operation-hence fixed wireless access. In effect, the fixed wireless access system provides for a direct alternative to or replacement for a fixed wireline connection. In practice, however, fixed wireless access systems are not installed to replace wireline systems, and there is not usually a viable alternative using wirelines.

The Use and Advantages of Radio for Fixed Network Access

In the modern `wired-society', it may seem a retrospective step that the public telecommunications world should be considering fixed wireless access. Why use radio, when fibre can be used as a solution for all types of telecommunications signal transport, and can provide for previously undreamt of capacity? There are various reasons, which we present in this chapter. We first describe the particular attributes of networks and services for which radio is ideally suited. We then consider the technological alternatives to contrast the benefits.

The main advantages of radio for fixed wireless access are:

* rapid manner in which access networks can be newly provided or existing networks can be complemented with new capacity;
* speed and ease of adding further customer lines for existing services;
* ability to offer new high bitrate access services;
* ease of realisation and the low investment needed to add large coverage areas to an access network;
* speed with which service can be installed for new customers;
* ease with which service can be provided in remote places, over difficult terrain or in places where other building restrictions may prevent easy wireline installation (e.g. in `historic' town centres);
* ease of redeployment of subscriber radio hardware and consequent security of the investment associated with a radio access network;
* inherent `shared medium' nature of radio-providing an ideal medium for `concentration' of connections as well as for `broadcast' and `asymmetric' transmission applications (i.e. those with different volumes of information to be transmitted in `transmit' and `receive' directions);
* relative ease and efficiency with which redundant or `back-up' connections can be realised with radio.

The Time to Consider Installing a Fixed Wireless Access Network

A fixed wireless access network is, of course, not suited to all occasions. It is, for example, always cheaper for a network operator to use his existing network (if he has one) rather than invest in new access network technology. Thus, an ex-monopoly operator is best advised to make the best of existing copper lineplant. A cable TV operator, meanwhile, should explore the potential of coaxial `cable modem' technology; and a new `city network' operator should install fibre for high capacity metropolitan networks. Nonetheless, even for these `established' operators, there comes a time when the network capacity in a given region is not sufficient to meet demand. At this point in time, major investment is necessary to provide for new capacity. This is when even the `established' operators are forced to pose themselves the same question that their newly licensed competition are asking "What is the most economic and effective way to provide a new access network infrastructure in a given area, for a given service?" The answer may be fixed wireless technology.