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Wireless is one of the most rapidly developing technologies in our time, with dazzling
new products and services emerging on an almost daily basis. These developments present
enormous challenges for communications engineers, as the demand for increased wireless
capacity grows explosively. Indeed, the discipline of wireless communications presents
many challenges to designers that arise as a result of the demanding nature of the PhySical
medium and the complexities in the dynamics of the underlying network.
標(biāo)簽：
Communications
Wireless
MIMO
上傳時(shí)間：
2020-05-28
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Multi-carrier modulation? Orthogonal Frequency Division Multi-
plexing (OFDM) particularly? has been successfully applied to
a wide variety of digital communications applications over the past
several years. Although OFDM has been chosen as the PhySical layer
standard for a diversity of important systems? the theory? algorithms?
and implementation techniques remain subjects of current interest.
This is clear from the high volume of papers appearing in technical
journals and conferences.
標(biāo)簽：
COMMUNICATIONS
MULTI-CARRIER
DIGITAL
上傳時(shí)間：
2020-05-31
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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(biāo)簽：
Multiple-Output
Multiple-Input
Channel
Models
上傳時(shí)間：
2020-05-31
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If you would like to follow along with some of the steps outlined in this book, we recommend that you
deploy Live Communications Server 2005 SP1 on a PhySical or virtual server running Microsoft
Windows Server 2003. To run Communicator 2005, you will need a PhySical or virtual PC running
Windows XP or Windows Server 2003. To fully test Microsoft Office integration with Communicator
2005, you need to be running Microsoft Office 2003 with Service Pack 2.
標(biāo)簽：
Communications
Professional
Server
Live
上傳時(shí)間：
2020-05-31
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The investigation of the propagation channel is becoming more and more important in mod-
ern wireless communication. The demand for spectral efficiency motivates exploitation of
all channels that can possibly be used for communications. Nowadays, a common trend for
designing PhySical layer algorithms is to adapt the transceiving strategy, either by maximizing
the diversity gains or by utilizing the coherence of the channels to improve the signal-to-noise
power ratio.
標(biāo)簽：
Characterization
Propagation
Channel
上傳時(shí)間：
2020-05-31
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-
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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-
I love telecommunications. It is powerful and it empowers, with
far-reaching consequences. It has demonstrated the potential to transform
society and business, and the revolution has only just begun. With the invention
of the telephone, human communications and commerce were forever changed: Time
and distance began to melt away as a barrier to doing business, keeping in touch
with loved ones, and being able to immediately respond to major world events.
Through the use of computers and telecommunications networks, humans have been
able to extend their powers of thinking, influence, and productivity, just as
those in the Industrial Age were able to extend the power of their muscles, or
PhySical self, through use of heavy machinery.
標(biāo)簽：
Telecommunications
Essentials
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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-
Driven by the rapid advancement of technology and the growing need of business
requirements, cyber communications are embedded in many PhySical systems. The
integration of cyber and PhySical capabilities leads to the creation of many applica-
tions with enormous societal impact and economic benefit. The emerging systems
that connect the cyber-world of computing and communications with the PhySical
world are cyber-PhySical systems (CPS).
標(biāo)簽：
Resiliency
Analytics
Security
and
上傳時(shí)間：
2020-06-07
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-
Sensors are points ofcontact betweenthe material world ofatoms, mass, andenergy
and the seemingly immaterial world of information, computation, and cognition.
Linking these two domains more tightly yields all sorts of practical benefits, such as
improvedinputdevicesforcomputers,moreeffectivemedicaldevices(implantedor
worn), more precise agricultural operations, better monitored buildings or bridges,
more secure payment systems, and more reliable sensor–actuator control systems.
There are many settings in which tighter coupling between digital and PhySical
planes can enhance safety, security, performance, and reliability.
標(biāo)簽：
Computational
RFID
上傳時(shí)間：
2020-06-08
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