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One of the prerequisites for the development of telecommunication services is the
understanding of the propagation of the waves, either acoustic, electromagnetic,
radio or light waves, which are used for the transmission of information.
In this work, we shall limit ourselves to the study of radio waves: this term
apply to the electromagnetic waves used in radio communications. Their
frequency spectrum is very broad, and is divided into the following frequency
bands : ELF waves (f < 3 kHz), VLF (3-30 kHz), LF waves (30-300 kHz), MF
waves (300-3000 kHz), HF (3-30 MHz), VHF waves (30-300 MHz), UHF waves
(300-3000 MHz), SHF waves (3-30 GHz), EHF waves (30-300 GHz) and sub-
EHF waves (300-3000 GHz).
標(biāo)簽：
Propagation
Radio
Wave
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2020-06-01
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An understanding of the policies, regulations, standards and techniques of radio spectrum
management is useful to those who manage and administrate it, to operators, to equipment
providers and to the users of wireless communication (i.e., all of us). For many years the author
has been deeply involved in ruling the RF spectrum at the national, regional and global levels.
The book is based on the professional experience of the author, his academic courses, presenta-
tions and tutorials in five continents. The book reflects this legacy and will be of use to engineers,
lawyers and economists, who serve the global industry of the wireless world; in it they may find
solutions to the problems they frequently encounter.
標(biāo)簽：
Management
Spectrum
Radio
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2020-06-01
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The need to develop reliable microelectronic devices capable of operating at high
speeds with complex functionality requires a better understanding of the factors
that govern the thermal performance of electronics. With an increased demand
on system reliability and performance combined with miniaturization of the
devices, thermal consideration has become a crucial factor in the design of elec-
tronic packages, from chip to system levels.
標(biāo)簽：
Telecommunications
Management
Equipment
Thermal
of
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2020-06-01
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T
his book covers basic communications theory and practical imple-
mentation of transmitters and receivers. In so doing, I focus on dig-
ital modulation, demodulation methods, probabilities, detection of
digital signals, and spread spectrum system design and analysis. This book
was written for those who want a good understanding of the basic prin-
ciples of digital wireless communication systems, including spread spec-
trum techniques. This book also provides a good intuitive and practical
approach to digital communications. Therefore it is a valuable resource for
anyoneinvolvedinwirelesscommunicationsandtransceiverdesignfordig-
ital communications. The reader will gain a broad understanding of basic
communication principles for transceiver design, digital communications,
and spread spectrum, along with examples of many types of commercial
and military data link systems.
標(biāo)簽：
Transceiver
System
Design
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2020-06-01
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In the two years since this book was first published, ultra wideband (UWB) has
advanced and consolidated as a technology, and many more people are aware of the
possibilities for this exciting technology. We too have expanded and consolidated
materials in this second edition in the hope that ‘Ultra Wideband: Signals and Systems
in Communication Engineering’ will continue to prove a useful tool for many students
and engineers to come to an understanding of the basic technologies for UWB.
標(biāo)簽：
Wideband
Signals
Systems
Ultra
and
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2020-06-01
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As I have increasingly moved away from the world of research and into
thatofmanagementandbusiness,ithasbecomeapparenttomethatthere
are many people from a nontechnical background who need to under-
standcellularsystemsinmoredetailinordertobeabletoperformtheir
job,beitanalyzingfinancialinvestments,runningcallcenters,ormarket-
ing cellular services.
標(biāo)簽：
understanding
Cellular
Radio
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2020-06-01
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The use of light to send messages is not new. Fires were used for signaling in
biblical times, smoke signals have been used for thousands of years and flashing
lights have been used to communicate between warships at sea since the days of
Lord Nelson.
The idea of using glass fibre to carry an optical communications signal originated
with Alexander Graham Bell. However this idea had to wait some 80 years for
better glasses and low-cost electronics for it to become useful in practical
situations.
標(biāo)簽：
Communications
understanding
Optical
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2020-06-01
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The dictionary definition of telecommunications is ‘communication over long
distance by cable, telegraph, telephone or broadcasting’, but since its initiation over
100yearsagothingshavemovedrapidly.Telecommunicationsisnowaverycomplex
industrywithmanydifferentpressures,operatinginahighlydynamic environment.It
is best viewed as part of a wider industry known as information and communication
technology (ICT). The purpose of this chapter is to explain where telecommunication
fits in, to highlight some of the complexities – hopefully to simplify them – and to
position the industry in today’s dynamic business environment.
標(biāo)簽：
Telecommunications
understanding
Business
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2020-06-01
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Telecommunications is today widely understood to mean the electrical means of
communicating over a distance. The first form of telecommunications was that of
the Telegraph, which was invented quite independently in 1837 by two scientists,
Wheatstone and Morse. Telegraphy was on a point-to-point unidirectional basis and
relied on trained operators to interpret between the spoken or written word and the
special signals sent over the telegraph wire. However, the use of telegraphy did
greatly enhance the operations of railways and, of course, the dissemination of news
and personal messages between towns.
標(biāo)簽：
Telecommunications
understanding
Networks
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2020-06-01
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Electrostatic discharge (ESD) phenomena have been known to mankind since the Greek
Empire when Thales of Miletus, one of the Seven Sages of Greece, noticed the attraction of
strands of hay to amber, leading to the coining of the word ‘‘electron.’’ In the 17th century,
Gilbert and Cabeo addressed the attractive and repulsive nature of electricity. In the 18th
century, a rapid increase of interest occurred for scientists in the understanding of electrical
physics—Gray, du Fay, Nollet, Musschenbroeck, Franklin, Watson, Aepinus, Canton,
標(biāo)簽：
Circuits
Devices
ESD
and
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2020-06-05
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