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The wireless market has experienced a phenomenal growth since the first second-
generation (2G) digital cellular networks, based on global system for mobile
COMMUNICATIONs (GSM) technology, were introduced in the early 1990s. Since then,
GSM has become the dominant global 2G radio access standard. Almost 80% of today’s
new subscriptions take place in one of the more than 460 cellular networks that use
GSM technology. This growth has taken place simultaneously with the large experienced
expansion of access to the Internet and its related multimedia services.
標(biāo)簽:
Performance
Evolution
GPRS
EDGE
GSM
and
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This book is intended to help electric power and telephone company
personnel and individuals interested in properly protecting critical tele-
COMMUNICATIONs circuits and equipment located in high voltage (HV)
environments and to improve service reliability while maintaining safe
working conditions. Critical teleCOMMUNICATIONs circuits are often
located in HV environments such as electric utility power plants,
substations, cell sites on power towers, and standalone telecommuni-
cations facilities such as 911 call centers and mountaintop telecom-
munications sites.
標(biāo)簽:
Protection
Voltage
High
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This book was conceived in such a special way. From our experience, and despite the
increasing interest that we perceived amongst the research community in HAPS,
there was not any book in the market entirely devoted to HAPS. We could only find
some satellite COMMUNICATIONs books including only fragments related to HAPS,
covering the ‘generalities’. A need for a reference book which could highlight state-
of-the-art HAPS-related topics was therefore envisaged. Moreover, most of the
information related to HAPS could only be found in technical reports, official
recommendations, conference proceedings and journal papers.
標(biāo)簽:
High-Altitude
Platforms
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Our original effort in writing this book was to create a starting point for those in
the business community who did not have a high level of technical expertise but
needed to have some understanding of the technical functions of their information
and communication technologies (ICT) in a corporate environment. As was true
with the first edition of this book, if you are already an engineer, find some other
form of pleasure reading—this text is not designed for you!
標(biāo)簽:
COMMUNICATIONs
Introduction
Technologies
to
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Fixed-mobile.convergence.and.voice-data.networks.have.merged.next-gen-
eration,.value-added.applications.and.integrated.multimedia.services,.com-
bining. Web. browsing,. instant. messaging,. presence,. voice. over. IP,. video.
conferencing,. application. sharing,. telephony,. unified. messaging,. multi-
media.content.delivery,.etc..on.top.of.different.network.technologies..The.
convergence.of.the.COMMUNICATIONs.networks.is.motivated.by.the.need.to.
support.many.forms.of.digital.traffic.as.well.as.to.amortize.implementation.
and.operational.costs.of.the.underlying.networks..Historically,.the.approach.
to. build. and. deploy. multimedia. services. has. focused. upon. single-point.
solutions..
標(biāo)簽:
Multimedia
Subsystem
Handbook
IMS
IP
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In order to improve the spectral efficiency in wireless COMMUNICATIONs, multiple
antennas are employed at both transmitter and receiver sides, where the resulting
system is referred to as the multiple-input multiple-output (MIMO) system. In
MIMO systems, it is usually requiredto detect signals jointly as multiple signals are
transmitted through multiple signal paths between the transmitter and the receiver.
This joint detection becomes the MIMO detection.
標(biāo)簽:
Complexity
Detection
MIMO
Low
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In the nineteenth century, scientists, mathematician, engineers and innovators started
investigating electromagnetism. The theory that underpins wireless COMMUNICATIONs was
formed by Maxwell. Early demonstrations took place by Hertz, Tesla and others. Marconi
demonstrated the first wireless transmission. Since then, the range of applications has
expanded at an immense rate, together with the underpinning technology. The rate of
development has been incredible and today the level of technical and commercial maturity
is very high. This success would not have been possible without understanding radio-
wave propagation. This knowledge enables us to design successful systems and networks,
together with waveforms, antennal and transceiver architectures. The radio channel is the
cornerstone to the operation of any wireless system.
標(biāo)簽:
LTE-Advanced
Generation
Next
and
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LTE-Advanced becomes a truly global standard for 4G cellular COMMUNICATIONs.
Relay, as one of the key technologies of LTE-Advanced, can significantly extend
the coverage, and improve the system throughput. LTE-A standards and tech-
nologies were described in several recent books where the limited pages for relay
feature prevent the detailed explanations of the technology. In this book, we tried
to provide an in-depth description of LTE-A relay development. More specifically,
significant portions are spent on relay channel modeling and potential technologies
during the study item phase of the development, although some of those tech-
nologies, such as Type 2 cooperative relay, multi-hop relay, relay with backhaul of
carrier aggregation, were not standardized in Release 10 LTE.
標(biāo)簽:
LTE-Advanced
Technology
Relay
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Nature is seldom kind. One of the most appealing uses for radio-
telephone systems—communication with people on the move—must over-
come radio transmission problems so difficult they challenge the imagina-
tion. A microwave radio signal transmitted between a fixed base station
and a moving vehicle in a typical urban environment exhibits extreme
variations in both amplitude and apparent frequency.
標(biāo)簽:
COMMUNICATIONs
Microwave
Mobile
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When we started thinking about writing the first edition of this book a few years ago, we had been
working together for more than five years on the borderline between propagation and signal processing.
Therefore, it is not surprising that this book deals with propagation models and design tools for MIMO
wireless COMMUNICATIONs. Yet, this book should constitute more than a simple combination of these
two domains. It hopefully conveys our integrated understanding of MIMO, which results from endless
controversial discussions on various multi-antenna related issues, as well as various interactions with
numerous colleagues. Obviously, this area of technology is so large that it is beyond our aim to cover all
aspects in details. Rather, our goal is to provide researchers, R&D engineers and graduate students with
a comprehensive coverage of radio propagation models and space–time signal processing techniques
for multi-antenna, multi-user and multi-cell networks.
標(biāo)簽:
Wireless
Networks
MIMO
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