-
Rapid progress in information and communications technology (ICT) induces
improved and new telecommunications services and contributes greatly to society
in general and to vendors and network and service providers. In addition to existing
services such as telephony or leased line services, spread of the Internet, the Internet
Protocol (IP) phone, and new communications services like IPTV are making great
progress with the development of digital subscriber lines (DSL) and high - speed
communications technologies like fi ber to the home (FTTH).
標(biāo)簽：
Telecommunications
Networks
上傳時(shí)間：
2020-06-01
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When 3GPP started standardizing the IMS a few years ago, most analysts expected the
number of IMS deploymentsto grow dramatically as soon the initial IMS specifications were
ready (3GPP Release 5 was functionallyfrozenin the first half of 2002and completedshortly
after that). While those predictions have proven to be too aggressive owing to a number of
upheavals hitting the ICT (Information and Communications Technologies) sector, we are
now seeing more and more commercial IMS-based service offerings in the market. At the
time of writing (May 2008), there are over 30 commercial IMS networks running live traffic,
addingup to over10million IMS users aroundthe world; the IMS is beingdeployedglobally.
In addition, there are plenty of ongoing market activities; it is estimated that over 130 IMS
contracts have been awarded to all IMS manufacturers. The number of IMS users will grow
substantially as these awarded contracts are launched commercially. At the same time, the
number of IMS users in presently deployed networks is steadily increasing as new services
are introduced and operators running these networks migrate their non-IMS users to their
IMS networks.
標(biāo)簽：
Multimedia
Subsystem
The
IMS
3G
IP
上傳時(shí)間：
2020-06-01
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Wireless communications has become a field of enormous scientific and economic interest. Recent
success stories include 2G and 3G cellular voice and data services (e.g., GSM and UMTS), wireless
local area networks (WiFi/IEEE 802.11x), wireless broadband access (WiMAX/IEEE 802.16x), and
digital broadcast systems (DVB, DAB, DRM). On the physical layer side, traditional designs typically
assume that the radio channel remains constant for the duration of a data block. However, researchers
and system designers are increasingly shifting their attention to channels that may vary within a block.
In addition to time dispersion caused by multipath propagation, these rapidly time-varying channels
feature frequency dispersion resulting from the Doppler effect. They are, thus, often referred to as
being “doubly dispersive.”
標(biāo)簽：
Time-Varying
Channels
上傳時(shí)間：
2020-06-01
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This book is an outgrowth of the pioneering development work done by InterDigital Com-
munication Corporation in 3rd Generation TDD WCDMA Technology. Many engineers
and managers were involved in this development, which spanned a wide range of tech-
nology areas, including system architecture, radio interface, radio modem design, radio
resource management and hardware/software implementation. In addition, TDD WCDMA
technology had many direct and indirect contributors across the globe in the context of
the development of the 3GPP TDD WCDMA Standard.
標(biāo)簽：
Wideband
TDD
上傳時(shí)間：
2020-06-01
上傳用戶：shancjb
-
Wireless networking is undergoing a transformation from what has
been primarily a medium for supporting voice traffic between telephones,
into what is increasingly becoming a medium for supporting traffic among
a variety of digital devices transmitting media of many types (voice,
data, images, video. etc.) Wireline networking underwent a similar
transformation in the 1990s, which led to an enormous build-up in the
capacity of such networks, primarily through the addition of new optical
fiber, switches and other infrastructure.
標(biāo)簽：
Multiusers
Detection
Wireless
Networks
上傳時(shí)間：
2020-06-01
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This chapter provides extensive coverage of existing mobile wireless technologies. Much of the
emphasis is on the highly anticipated 3G cellular networks and widely deployed wireless local
area networks (LANs), as the next-generation smart phones are likely to offer at least these two
types of connectivity. Other wireless technologies that either have already been commercialized or
are undergoing active research and standardization are introduced as well. Because standardization
plays a crucial role in developing a new technology and a market, throughout the discussion
standards organizations and industry forums or consortiums of some technologies are introduced.
In addition, the last section of this chapter presents a list of standards in the wireless arena.
標(biāo)簽：
Networking
Wireless
Complete
上傳時(shí)間：
2020-06-01
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-
Applications of microelectromechanical systems (MEMS) and microfabrica-
tion have spread to different fields of engineering and science in recent years.
Perhaps the most exciting development in the application of MEMS technol-
ogy has occurred in the biological and biomedical areas. In addition to key
fluidic components, such as microvalves, pumps, and all kinds of novel
sensors that can be used for biological and biomedical analysis and mea-
surements, many other types of so-called micro total analysis systems (TAS)
have been developed.
標(biāo)簽：
Applications
Technologies
Bio-MEMS
and
上傳時(shí)間：
2020-06-06
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For more than three decades, Micro Electro Mechanical Systems (MEMS) have
steadily transitioned out of research labs and into production forming a more than $10 billion
market [1]. MEMS devices such as accelerometers, pressure sensors and microphones, to name
a few, have seen immense utilization, particularly in the consumer electronics market, because
of their compact sizes and minute power consumptions. In addition, these devices benefit from
batch fabrication, which has enabled year-over-year reductions in cost [2]. In recent years,
標(biāo)簽：
Frequency
Tunable
MEMS
上傳時(shí)間：
2020-06-06
上傳用戶：shancjb
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This book is written for engineers involved in the operation, control, and
planning of electric power systems. In addition, the book provides information and
tools for researchers working in the fields of power system security and stability. The
book consists of two volumes. The first volume provides traditional techniques for the
stability analysis of large scale power systems. In addition, an overview of the main
drivers and requirements for modernization of the traditional methods for online
applications are discussed. The second volume provides techniques for online security
assessment and corrective action studies. In addition, the impact of variable generation
on the security of power systems is considered in the second volume. The first volume
may be considered as a background builder while the second volume is intended for
the coverage of edge techniques and methods for online dynamic security studies.
標(biāo)簽：
Security
Dynamic
上傳時(shí)間：
2020-06-07
上傳用戶：shancjb
-
This manuscript is a partial draft of a book to be published in early 1994 by AddisonWesley (ISBN 0-201-63337-X). Addison-Wesley has given me permission to make
drafts of the book available to the Tcl community to help meet the need for introductory documentation on Tcl and Tk until the book becomes available. Please observe
the restrictions set forth in the copyright notice above: you’re welcome to make a
copy for yourself or a friend but any sort of large-scale reproduction or reproduction
for profit requires advance permission from Addison-Wesley
標(biāo)簽：
Toolkit
上傳時(shí)間：
2020-07-05
上傳用戶：
