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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
上傳時間：
2020-05-27
上傳用戶：shancjb
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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
上傳用戶：shancjb
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In recent years, the research and developments in the area of RF and microwave
technologies have progressed significantly due to the growing demand for applica-
bility in wireless communication technologies. Starting from 1992, wireless com-
munication technologies have become quite mature. In the modern era of electronic
developments, design of wireless handsets is an example of integration of many di-
verse skill sets. Classical books in the areas of microwave technology provide us
with an in-depth knowledge of electromagnetic fundamentals.
標簽：
Front-Ends
Receiver
Modern
上傳時間：
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.
標簽：
Multiple-Output
Multiple-Input
Channel
Models
上傳時間：
2020-05-31
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All wireless communication standards, existing and under development, adopt or
consider adopting orthogonal frequency-division multiplexing (OFDM) as the
modulation technique. It is clear that OFDM has become the definitive modulation
scheme in current and future wireless communication systems.
標簽：
Baseband
Receiver
Design
OFDM
上傳時間：
2020-05-31
上傳用戶：shancjb
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Many good textbooks exist on probability and random processes written at the under-
graduate level to the research level. However, there is no one handy and ready book
that explains most of the essential topics, such as random variables and most of their
frequently used discrete and continuous probability distribution functions; moments,
transformation, and convergences of random variables; characteristic and generating
functions; estimation theory and the associated orthogonality principle; vector random
variables; random processes and their autocovariance and cross-covariance functions; sta-
tionarity concepts; and random processes through linear systems and the associated
Wiener and Kalman filters.
標簽：
Probability
Processes
Random
and
上傳時間：
2020-05-31
上傳用戶：shancjb
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Software Radio (SR) is one of the most important emerging technologies for the
future of wireless communication services. By moving radio functionality into
software, it promises to give flexible radio systems that are multi-service, multi-
standard, multi-band, reconfigurable and reprogrammable by software.
Today’s radios are matched to a particular class of signals that are well defined
bytheircarrierfrequencies,modulationformatsandbandwidths.Aradiotransmitter
today can only up convert signals with well-defined bandwidths over defined center
frequencies, while, on the other side of the communication chain, a radio receiver
can only down convert well-defined signal bandwidths, transmitted over specified
carrier frequencies.
標簽：
Software
Radio
上傳時間：
2020-06-01
上傳用戶：shancjb
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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.
標簽：
Stochastic
Geometry
Networks
Wireless
Volume
and
II
上傳時間：
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.
標簽：
Understanding_the_Basics_of_MIMO
上傳時間：
2020-06-01
上傳用戶：shancjb
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Wavelength division multiplexing (WDM) refers to a multiplexing and transmission
scheme in optical telecommunications fibers where different wavelengths, typically
emitted by several lasers, are modulated independently (i.e., they carry independent
information from the transmitters to the receivers). These wavelengths are then
multiplexed in the transmitter by means of passive WDM filters, and likewise they
are separated or demultiplexed in the receiver by means of the same filters or
coherent detection that usually involves a tunable local oscillator (laser).
標簽：
Multiplexing
Wavelength
Division
上傳時間：
2020-06-01
上傳用戶：shancjb
