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Many times I have been asked to explain “ briefl y ” how SDH, SONET, and the
OTN “ exactly ” work. The questions came mainly from new colleagues, stu-
dents, and users of these technologies, personally or via the usenet newsgroup
comp.dcom.sdh - sonet. I could have referred them to the standards documents,
but to provide a more consistent and clear answer I decided to write this
pocket guide. The objective of this book is that it can be used both as an
introduction as well as a reference guide to these technologies and their spe-
cifi c standards documents.
標簽：
Generation
Transport
Optical
ComSoc
Guide
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In the preparation of this book, our objective was to provide an advanced understanding of emerging
telecommunications systems, their significance, and the anticipated role these systems will play in the
future. With the help of our talented associated editors and contributors, we believe we have accomplished
this. By addressing voice, Internet, traffic management, and future trends, we feel our readers will be
knowledgeable about current and future telecommunications systems.
標簽：
CRC
Handbook
of Modern
Telecommunications
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The rapid growth in mobile communications has led to an increasing demand for wide-
band high data rate communications services. In recent years, Distributed Antenna
Systems (DAS) has emerged as a promising candidate for future (beyond 3G or 4G)
mobile communications, as illustrated by projects such as FRAMES and FuTURE. The
architecture of DAS inherits and develops the concepts of pico- or micro-cell systems,
where multiple distributed antennas or access points (AP) are connected to and con-
trolled by a central unit.
標簽：
Distributed
Antenna
Systems
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Multiuser multiple-input-multiple-output (MU-
MIMO) systems are known to be hindered by dimensionality
loss due to channel state information (CSI) acquisition overhead.
In this paper, we investigate user-scheduling in MU-MIMO
systems on account of CSI acquisition overhead, where a base
station dynamically acquires user channels to avoid choking the
system with CSI overhead.
標簽：
Acquisition
Dynamic
Channel
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The objective of this book is to allow the reader to predict the received
signal power produced by a particular radio transmitter. The first two
chapters examine propagation in free space for point-to-point and
point-to-area transmission, respectively. This is combined with a dis-
cussion regarding the characteristics of antennas for various purposes. In
chapter 3, the effect of obstacles, whether buildings or mountains, is
discussed and analytical methods, whereby the strength of a signal is the
shadow of an obstacle can be predicted, are presented.
標簽：
Propagation
Essentials
Radio
Wave
of
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With the rapid growth in the number of wireless applications, services and devices,
using a single wireless technology such as a second generation (2G) and third gener-
ation (3G) wireless system would not be efficient to deliver high speed data rate and
quality-of-service (QoS) support to mobile users in a seamless way. The next genera-
tion wireless systems (also sometimes referred to as Fourth generation (4G) systems)
are being devised with the vision of heterogeneity in which a mobile user/device will
be able to connect to multiple wireless networks (e.g., WLAN, cellular, WMAN)
simultaneously.
標簽：
Heterogeneous
Wireless
Networks
Access
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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.
標簽：
HSDPAHSUPA
Access
Speed
Radio
UMTS
High
for
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In this book, we study the interference cancellation and detection problem in
multiantenna multi-user scenario using precoders. The goal is to utilize multiple
antennas to cancel the interference without sacrificing the diversity or the com-
plexity of the system.
標簽：
Cancellation6
Interference
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To meet the future demand for huge traffic volume of wireless data service, the research on the fifth generation
(5G) mobile communication systems has been undertaken in recent years. It is expected that the spectral and energy
efficiencies in 5G mobile communication systems should be ten-fold higher than the ones in the fourth generation
(4G) mobile communication systems. Therefore, it is important to further exploit the potential of spatial multiplexing
of multiple antennas. In the last twenty years, multiple-input multiple-output (MIMO) antenna techniques have been
considered as the key techniques to increase the capacity of wireless communication systems. When a large-scale
antenna array (which is also called massive MIMO) is equipped in a base-station, or a large number of distributed
antennas (which is also called large-scale distributed MIMO) are deployed, the spectral and energy efficiencies can
be further improved by using spatial domain multiple access. This paper provides an overview of massive MIMO
and large-scale distributed MIMO systems, including spectral efficiency analysis, channel state information (CSI)
acquisition, wireless transmission technology, and resource allocation.
標簽：
Large-scale
Antenna
Systems
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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.
標簽：
Complexity
Detection
MIMO
Low
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