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.
标签: Communications5 Wireless MIMO
上传时间: 2020-05-28
上传用户: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.
标签: Multiple-Output Multiple-Input Channel models
上传时间: 2020-05-31
上传用户:shancjb
This book is about multipoint cooperative communication, a key technology to overcome the long-standing problem of limited transmission rate caused by inter- point interference. However, the multipoint cooperative communication is not an isolated technology. Instead, it covers a vast range of research areas such as the multiple-input multiple-outputsystem, the relay network, channel state information issues, inter-point radio resource management operations, coordinated or joint transmissions, etc. We suppose that any attempt trying to thoroughly analyze the multipoint cooperative communication technology might end up working on a cyclopedia for modern communication systems and easily get lost in discussing all kinds of cooperative communication schemes as well as the associated models and their variations.
标签: Communication Multi-point Cooperative Systems
上传时间: 2020-05-31
上传用户: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.
标签: Communication Propagation Handbook Wireless for
上传时间: 2020-05-31
上传用户:shancjb
This paper presents a Hidden Markov Model (HMM)-based speech enhancement method, aiming at reducing non-stationary noise from speech signals. The system is based on the assumption that the speech and the noise are additive and uncorrelated. Cepstral features are used to extract statistical information from both the speech and the noise. A-priori statistical information is collected from long training sequences into ergodic hidden Markov models. Given the ergodic models for the speech and the noise, a compensated speech-noise model is created by means of parallel model combination, using a log-normal approximation. During the compensation, the mean of every mixture in the speech and noise model is stored. The stored means are then used in the enhancement process to create the most likely speech and noise power spectral distributions using the forward algorithm combined with mixture probability. The distributions are used to generate a Wiener filter for every observation. The paper includes a performance evaluation of the speech enhancer for stationary as well as non-stationary noise environment.
标签: Telecommunications Processing Signal for
上传时间: 2020-06-01
上传用户:shancjb
Part I provides a compact survey on classical stochastic geometry models. The basic models defined in this part will be used and extended throughout the whole monograph, and in particular to SINR based models. Note however that these classical stochastic models can be used in a variety of contexts which go far beyond the modeling of wireless networks. Chapter 1 reviews the definition and basic properties of Poisson point processes in Euclidean space. We review key operations on Poisson point processes (thinning, superposition, displacement) as well as key formulas like Campbell’s formula. Chapter 2 is focused on properties of the spatial shot-noise process: its continuity properties, its Laplace transform, its moments etc. Both additive and max shot-noise processes are studied. Chapter 3 bears on coverage processes, and in particular on the Boolean model. Its basic coverage characteristics are reviewed. We also give a brief account of its percolation properties. Chapter 4 studies random tessellations; the main focus is on Poisson–Voronoi tessellations and cells. We also discuss various random objects associated with bivariate point processes such as the set of points of the first point process that fall in a Voronoi cell w.r.t. the second point process.
标签: Stochastic Geometry Networks Wireless Volume and
上传时间: 2020-06-01
上传用户:shancjb
Failure analysis is invaluable in the learning process of electrostatic discharge (ESD) and electrical overstress (EOS) protection design and development [1–8]. In the failure analysis of EOS, ESD, and latchup events, there are a number of unique failure analysis processes andinformationthatcanprovidesignificantunderstandingandillumination[4].Today,thereis still no design methodology or computer-aided design (CAD) tool which will predict EOS, ESDprotectionlevels,andlatchupinasemiconductorchip;thisisoneofthesignificantreasons why failure analysis is critical to the ESD design discipline.
标签: Mechanisms Failure models ESD and
上传时间: 2020-06-05
上传用户:shancjb
The Raspberry Pi has become a computing phenomenon. This single-board miniature computer, first released in February 2012 by the Raspberry Pi Foundation, has grown into a series of nearly a dozen models that have sold a total of more than 10 million units in five years. Inexpensive to buy and to run, Raspberry Pi computers are great for enthusiasts, good for games, and fun for children. Raspberry Pi computers are also terrific in the classroom, enabling you to put on each desk an easily-manageable computer on which students can do everything from learning Internet use and essential office software skills, through grasping programming basics in an easy-to-learn format, to performing full-on programming in Python, Java, C, and other languages. Better yet, you can install all the software needed for those activities automatically alongside the operating system.
标签: Deploying Classroom Raspberry the Pi in
上传时间: 2020-06-06
上传用户:shancjb
Thepredecessorvolumeofthisbookwaspublishedin1996.Intheyears since then, some things have changed and some have not. Two of the things that have not changed are the desire for better models and faster simulations. I performed the original simulations on my “hyperfast” 133-MHz computer! At the time, I thought if I could just getafastercomputer,allofourSPICEproblemswouldbehistory,right? TodayIamsimulatingonacomputerthathasa2.6-GHzprocessorwith 512 MB of RAM, and I would still say that simulations run too slow. The computer technology has evolved, but so have the models. In 1996 wewereperformingsimulationson100-kHzpowerconverters,whereas today I routinely see 1- and 2-MHz power converters.
标签: Switch-Mode Simulation Supply Power
上传时间: 2020-06-07
上传用户:shancjb
Simulation is experimentation with models. For system design, research, and edu- cation, simulations must not only construct and modify many different models but also store and access a large volume of results. That is practical only with models programmed on computers [1,2]
上传时间: 2020-06-10
上传用户:shancjb