-
Free Space Optical Communication (FSOC) is an effective alternative technology to
meet the Next Generation Network (NGN) demands as well as highly secured (mili-
tary) communications. FSOC includes various advantages like last mile access, easy
installation, free of Electro Magnetic Interference (EMI)/Electro Magnetic Compatibil-
ity (EMC) and license free access etc. In FSOC, the optical beam propagation in the
turbulentatmosphereisseverelyaffectedbyvariousfactorssuspendedinthechannel,
geographicallocationoftheinstallationsite,terraintypeandmeteorologicalchanges.
Therefore a rigorous experimental study over a longer period becomes significant to
analyze the quality and reliability of the FSOC channel and the maximum data rate
that the system can operate since data transmission is completely season dependent.
標簽：
Communication
Optical
System
Space
Free
上傳時間：
2020-05-27
上傳用戶：shancjb
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An optical fiber amplifier is a key component for enabling efficient transmission of
wavelength-divisionmultiplexed(WDM)signalsoverlongdistances.Eventhough
many alternative technologies were available, erbium-doped fiber amplifiers won
theraceduringtheearly1990sandbecameastandardcomponentforlong-haulopti-
caltelecommunicationssystems.However,owingtotherecentsuccessinproducing
low-cost, high-power, semiconductor lasers operating near 1450 nm, the Raman
amplifiertechnologyhasalsogainedprominenceinthedeploymentofmodernlight-
wavesystems.Moreover,becauseofthepushforintegratedoptoelectroniccircuits,
semiconductor optical amplifiers, rare-earth-doped planar waveguide amplifiers,
and silicon optical amplifiers are also gaining much interest these days.
標簽：
propagation
Light
Media
Gain
in
上傳時間：
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.
標簽：
LTE-Advanced
Generation
Next
and
上傳時間：
2020-05-27
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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.
標簽：
Wireless
Networks
MIMO
上傳時間：
2020-05-28
上傳用戶：shancjb
-
When we started thinking about writing this book, 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
wirelesscommunications.Yet, thisbookshouldconstitutemorethanasimplecombination
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 was beyond our aim to cover all aspects in details. Rather, our goal has
been to provide researchers, R&D engineers and graduate students with a comprehensive
coverage of radio propagation models and space–time coding techniques.
標簽：
Communications5
Wireless
MIMO
上傳時間：
2020-05-28
上傳用戶：shancjb
-
Many wireless communications channels consist of multiple signal paths from the
transmitter to receiver. This multiplicity of paths leads to a phenomenon known
as multipath fading. The multiple paths are caused by the presence of objects in the
physical environment that, through the mechanisms of propagation, alter the path of
radiated energy. These objects are referred to as scatterers. In the past, researchers
often looked at ways to mitigate multipath scattering, such as in diversity systems.
Multiple-input, multiple-output (MIMO) systems, on the other hand, use multipath
diversity to their advantage; a MIMO system has the ability to translate increased
spatial diversity into increased channel capacity.
標簽：
Multiple-Output
Multiple-Input
Channel
Models
上傳時間：
2020-05-31
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Some tine ago it become apparent the the first edition of this book was rapidly approaching its sell-by date,since many aspects needed revise.There were two obvious courses of action : to forget the whole thing and concentrate my energies on other pursuits such as golf or fishing, or to embark on a new edition.For several reasons Iwas persuaded that a new edition was a worthwhile endeavour;many people had made complimentary remakrs or written complinentary letters about the first edition and I understood that it had become a recommended text for several postgraduate coures.
標簽：
TMobile
Radio
propagation
Channel
上傳時間：
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.”
標簽：
Time-Varying
Channels
上傳時間：
2020-06-01
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The use of optical free-space emissions to provide indoor wireless commu-
nications has been studied extensively since the pioneering work of Gfeller
and Bapst in 1979 [1]. These studies have been invariably interdisciplinary in-
volving such far flung areas such as optics design? indoor propagation studies?
electronics design? communications systems design among others. The focus
of this text is on the design of communications systems for indoor wireless
optical channels. Signalling techniques developed for wired fibre optic net-
works are seldom efficient since they do not consider the bandwidth restricted
nature of the wireless optical channel.
標簽：
Communication
Wireless
Optical
Systems
上傳時間：
2020-06-01
上傳用戶：shancjb
