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During the past decade, many wireless communication techniques have been
developedto achievevariousgoals suchas higherdata rate,morerobustlink quality,
and higher number of users in a given bandwidth. For wireless communication
systems, depending on the availability of a feedback link, two approaches can be
considered: namely open and closed loop. Open loop communication system that
does not exploit the channel knowledge at the transmitter is now well understood
from both a theoretical and practical point of view.
標(biāo)簽:
Communication
Strategies
Feedback
Wireless
for
上傳時(shí)間:
2020-05-27
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With the rapid expansion of wireless consumer products,there has been a con-
siderable increase in the need for radio-frequency (RF) planning, link plan-
ning, and propagation modeling.A network designer with no RF background
may find himself/herself designing a wireless network. A wide array of RF
planning software packages can provide some support, but there is no substi-
tute for a fundamental understanding of the propagation process and the lim-
itations of the models employed. Blind use of computer-aided design (CAD)
programs with no understanding of the physical fundamentals underlying the
process can be a recipe for disaster. Having witnessed the results of this
approach, I hope to spare others this frustration.
標(biāo)簽:
Introduction
Propagation
to
RF
上傳時(shí)間:
2020-05-27
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By definition, the term “mobile-radio communications” describes any
radio communication link between two terminals of which one or both
are in motion or halted at unspecified locations and of which one may
actually be a fixed terminal such as a base station. This definition
applies to both mobile-to-mobile and mobile-to-fixed radio communica-
tion links. The mobile-to-mobile link could in fact consist of a mobile-
to-fixed-to-mobile radio communication link.The term “mobile” applies
to land vehicles, ships at sea, aircraft, and communications satellites.
In tactical situations, mobile-radio systems may include any or all of
these types of mobile terminals.
標(biāo)簽:
Communications
Engineering
Mobile
上傳時(shí)間:
2020-05-30
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Optical wireless communication is an emerging and dynamic research and development
area that has generated a vast number of interesting solutions to very complicated
communication challenges. For example, high data rate, high capacity and minimum
interference links for short-range communication for inter-building communication,
computer-to-computer communication, or sensor networks. At the opposite extreme is
a long-range link in the order of millions of kilometers in the new mission to Mars
and other solar system planets.
標(biāo)簽:
Communication
Wireless
Optical
Systems
上傳時(shí)間:
2020-05-31
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Ever since ancient times, people continuously have devised new techniques and
technologies for communicating their ideas, needs, and desires to others. Thus,
many forms of increasingly complex communication systems have appeared
over the years. The basic motivations behind each new one were to improve the
transmission fidelity so that fewer errors occur in the received message, to
increase the transmission capacity of a communication link so that more infor-
mation could be sent, or to increase the transmission distance between relay sta-
tions so that messages can be sent farther without the need to restore the signal
fidelity periodically along its path.
標(biāo)簽:
Communications
Essentials
Optical
上傳時(shí)間:
2020-05-31
上傳用戶:shancjb
-
Wireless means different things to different people. For this book, it refers
to the radio systems that provide point-to-point, point-to-multipoint, and
Earth-space communications over transmission links that propagate outside
buildings through the lower atmosphere. Wireless systems are being built
that provide data transmission between computers and other devices on
one’s own desk. These are part of the wireless world but not the part where,
except for interference perhaps, the atmosphere has any influence. The intent
of this book is to provide a description of the physical phenomena that can
affect propagation through the atmosphere, present sample measurements
and statistics, and provide models that system designers can use to calculate
their link budgets and estimate the limitations the atmosphere may place on
their design.
標(biāo)簽:
Communication
Propagation
Handbook
Wireless
for
上傳時(shí)間:
2020-05-31
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The book is written for those concerned with the design and performance of satellite
communications systems employed in fixed point-to-point, broadcasting, mobile, radio-
navigation,data-relay,computercommunications,andrelatedsatellite-basedapplications.The
recentrapidgrowthinsatellitecommunicationshascreatedaneedforaccurateinformationon
both satellite communications systems engineering and the impact of atmospheric effects on
satellite link design and system performance. This book addresses that need for the first time
in a single comprehensive source.
標(biāo)簽:
Communications
Satellite
Systems
上傳時(shí)間:
2020-06-01
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A wireless communication network can be viewed as a collection of nodes, located in some domain, which
can in turn be transmitters or receivers (depending on the network considered, nodes may be mobile users,
base stations in a cellular network, access points of a WiFi mesh etc.). At a given time, several nodes
transmit simultaneously, each toward its own receiver. Each transmitter–receiver pair requires its own
wireless link. The signal received from the link transmitter may be jammed by the signals received from
the other transmitters. Even in the simplest model where the signal power radiated from a point decays in
an isotropic way with Euclidean distance, the geometry of the locations of the nodes plays a key role since
it determines the signal to interference and noise ratio (SINR) at each receiver and hence the possibility of
establishing simultaneously this collection of links at a given bit rate. The interference seen by a receiver is
the sum of the signal powers received from all transmitters, except its own transmitter.
標(biāo)簽:
Stochastic
Geometry
Networks
Wireless
Volume
and
II
上傳時(shí)間:
2020-06-01
上傳用戶:shancjb
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T
his book covers basic communications theory and practical imple-
mentation of transmitters and receivers. In so doing, I focus on dig-
ital modulation, demodulation methods, probabilities, detection of
digital signals, and spread spectrum system design and analysis. This book
was written for those who want a good understanding of the basic prin-
ciples of digital wireless communication systems, including spread spec-
trum techniques. This book also provides a good intuitive and practical
approach to digital communications. Therefore it is a valuable resource for
anyoneinvolvedinwirelesscommunicationsandtransceiverdesignfordig-
ital communications. The reader will gain a broad understanding of basic
communication principles for transceiver design, digital communications,
and spread spectrum, along with examples of many types of commercial
and military data link systems.
標(biāo)簽:
Transceiver
System
Design
上傳時(shí)間:
2020-06-01
上傳用戶:shancjb
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An acronym for Multiple-In, Multiple-Out, MIMO communication sends the same data as several signals
simultaneously through multiple antennas, while still utilizing a single radio channel. This is a form of
antenna diversity, which uses multiple antennas to improve signal quality and strength of an RF link. The
data is split into multiple data streams at the transmission point and recombined on the receive side by
another MIMO radio configured with the same number of antennas. The receiver is designed to take
into account the slight time difference between receptions of each signal, any additional noise or
interference, and even lost signals.
標(biāo)簽:
Understanding_the_Basics_of_MIMO
上傳時(shí)間:
2020-06-01
上傳用戶:shancjb