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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.
標簽：
Introduction
Propagation
to
RF
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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
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2020-05-27
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This book presents millimeter wave communication system design and analysis at the
level to produce an understanding of the interaction between a wireless system and its
front end so that the overall performance can be predicted. Gigabit wireless commu-
nications require a considerable amount of bandwidth, which can be supported by
millimeter waves. Millimeter wave technology has come of age, and at the time of
writing the standards of IEEE 802.15.3c, WiGig, Wireless HD TM , and the European
Computer Manufacturers Association have recently been finalized.
標簽：
Communication
Millimeter
Systems
Wave
上傳時間：
2020-05-28
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At the macroscopic level of system layout, the most important issue is path loss. In the
older mobile radio systems that are limited by receiver noise, path loss determines SNR and
the maximum coverage area. In cellular systems, where the limiting factor is cochannel
interference, path loss determines the degree to which transmitters in different cells interfere
with each other, and therefore the minimum separation before channels can be reused.
標簽：
Characteristics
Channel
Mobile
上傳時間：
2020-05-30
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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.
標簽：
Communications
Engineering
Mobile
上傳時間：
2020-05-30
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This is believed to be the first book that takes a view of nanotechnology from a
telecommunications and networking perspective. Nanotechnology refers to the manip-
ulation of materials at the atomic or molecular level. Nanotechnology is getting a lot
of attention of late not only in academic settings and in laboratories around the
world, but also in government and venture capitalists’ initiatives. There now is a
major drive to commercialize the technology by all sorts of firms, ranging from start-
ups to Fortune 100 companies.
標簽：
Nanotechnology
Applications
上傳時間：
2020-05-31
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Before delving into the details of orthogonal frequency division multiplexing (OFDM), relevant
background material must be presented first. The purpose of this chapter is to provide the necessary
building blocks for the development of OFDM principles. Included in this chapter are reviews of stochastic
and random process, discrete-time signals and systems, and the Discrete Fourier Transform (DFT). Tooled
with the necessary mathematical foundation, we proceed with an overview of digital communication
systems and OFDM communication systems. We conclude the chapter with summaries of the OFDM
wireless LAN standards currently in existence and a high-level comparison of single carrier systems versus
OFDM.
標簽：
Wireless
OFDM
LANS
上傳時間：
2020-05-31
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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.
標簽：
Communication
Wireless
Optical
Systems
上傳時間：
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.
標簽：
Communications
Essentials
Optical
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2020-05-31
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This book is a result of the recent rapid advances in two related technologies: com-
munications and computers. Over the past few decades, communication systems
have increased in complexity to the point where system design and performance
analysis can no longer be conducted without a significant level of computer sup-
port. Many of the communication systems of fifty years ago were either power or
noise limited. A significant degrading effect in many of these systems was thermal
noise, which was modeled using the additive Gaussian noise channel.
標簽：
Communication
Principles
Simulation
Systems
of
上傳時間：
2020-05-31
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