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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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2020-05-27
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Someone who wants to get to know the customs of a country frequently
receives the advice to learn the language of that country. Why? Because the dif-
ferences that distinguish the people of one country from those of another are
reflected in the language. For example, the people of the islands of the Pacific
do not have a term for war in their language. Similarly, some native tribes in
the rain forests of the Amazon use up to 100 different terms for the color green.
標(biāo)簽：
NETWORKS
GSM
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The first Third Generation Partnership Project (3GPP) Wideband Code Division
Multiple Access (WCDMA) NETWORKS were launched during 2002. By the end of 2005
there were 100 open WCDMA NETWORKS and a total of over 150 operators having
frequency licenses for WCDMA operation. Currently, the WCDMA NETWORKS are
deployedinUniversalMobileTelecommunicationsSystem(UMTS)bandaround2GHz
in Europe and Asia including Japan and Korea. WCDMA in America is deployed in the
existing 850 and 1900 spectrum allocations while the new 3G band at 1700/2100 is
expected to be available in the near future. 3GPP has defined the WCDMA operation
also for several additional bands, which are expected to be taken into use during the
coming years.
標(biāo)簽：
HSDPAHSUPA
Access
Speed
Radio
UMTS
High
for
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2020-05-27
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In this paper we revisit hybrid analog-digital precoding systems with emphasis on their modelling
and radio-frequency (RF) losses, to realistically evaluate their benefits in 5G system implementations.
For this, we decompose the analog beamforming NETWORKS (ABFN) as a bank of commonly used RF
components and formulate realistic model constraints based on their S-parameters. Specifically, we
concentrate on fully-connected ABFN (FC-ABFN) and Butler NETWORKS for implementing the discrete
Fourier transform (DFT) in the RF domain. The results presented in this paper reveal that the performance
and energy efficiency of hybrid precoding systems are severely affected, once practical factors are
considered in the overall design. In this context, we also show that Butler RF NETWORKS are capable of
providing better performances than FC-ABFN for systems with a large number of RF chains.
標(biāo)簽：
Analog-Digital
Precoding
Hybrid
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This book is intended for the RF planners, to serve as a practical tool in their daily work
designing indoor radio distribution systems. It is not a complete book about all the deep
aspects and corners of GSM, DCS, UMTS and HSPA NETWORKS, or all the core network
systems. It is dedicated to the last 10–70 m of the network, the indoor air interface between
the mobile user and the indoor mobile network.
標(biāo)簽：
Practical
Planning
Indoor
Guide
Radio
GSM
for
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2020-05-27
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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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2020-05-27
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This book addresses two aspects of network operation quality; namely, resource
management and fault management.
Network operation quality is among the functions to be fulfilled in order to offer
quality of service, QoS, to the end user. It is characterized by four parameters:
– packet loss;
– delay;
– jitter, or the variation of delay over time;
– availability.
Resource management employs mechanisms that enable the first three parameters
to be guaranteed or optimized. Fault management aims to ensure continuity of service.
標(biāo)簽：
Ethernet
NETWORKS
MPLS
and
IP
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2020-05-27
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For nearly a hundred years telecommunications provided mainly voice services and very low speed
data (telegraph and telex). With the advent of the Internet, several data services became mainstream
in telecommunications; to the point that voice is becoming an accessory to IP-centric data NETWORKS.
Today, high-speed data services are already part of our daily lives at work and at home (web surfing,
e-mail, virtual private NETWORKS, VoIP, virtual meetings, chats...). The demand for high-speed data
services will grow even more with the increasing number of people telecommuting.
標(biāo)簽：
WiMAX
WLAN
LTE
and
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2020-05-27
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This books attempts to provide an extensive overview on Long-Term Evolution
(LTE) NETWORKS. Understanding LTE and its Performance is purposely written to
appeal to a broad audience and to be of value to anyone who is interested in 3GPP
LTE or wireless broadband NETWORKS more generally. The aim of this book is to
offer comprehensive coverage of current state-of-the-art theoretical and techno-
logical aspects of broadband mobile and wireless NETWORKS focusing on LTE. The
presentation starts from basic principles and proceeds smoothly to most advanced
topics. Provided schemes are developed and oriented in the context of very actual
closed standards, the 3 GPPP LTE.
標(biāo)簽：
Performance
LTE
and
its
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2020-05-27
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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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2020-05-27
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