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Simulation of Local Area Networks

by Matthew N. Sadiku

A fast-growing area in the communications industry is the internetworking of an ever-increasing proliferation of computers, particularly via local area networks (LANs). The LAN is a resource-sharing data communications network being used by many offices to interchange information such as electronic mail, word processing, and files among computers and other devices. This unique book shows the user how to establish the performance characteristics of a LAN before putting it to use in a particular type of situation. Simulation of Local Area Networks consists of eight chapters, each with its own extensive list of references. The first chapter provides a brief review of local area networks, and the second chapter gives the analytical models of popular LANs-token-passing bus and ring networks, CSMA/CD LANs, and star networks. Chapter 3 covers general principles of simulation, and Chapter 4 discusses fundamental concepts in probability and statistics relating to simulation modeling. Materials in Chapters 3 and 4 are specifically applied in developing simulation models on token-passing LANs, CSMA/CD LANs, and star LANs in Chapters 5 through 7. The computer code in Chapters 5, 6, and 7 is divided into segments, and a detailed explanation of each segment is provided. The last chapter reviews special-purpose languages such as GPSS, SIMSCRIPT, GASP, SIMULA, SLAM, and RESQ. Helpful criteria for language selection are included. The entire code is put together in the appendixes. This book has two major advantages over existing texts. First, it uses C, a well-developed general-purpose language that is familiar to most analysts. Second, the text specifically applies the simulation principles to local area networks. No other book available shows the systems analyst how to evaluate the performance of existing or proposed systems under different kinds of conditions.

Simulation of Optical Soliton Control in Micro- and Nanoring Resonator Systems

by Suzairi Daud Sevia Mahdaliza Idrus Jalil Ali

This book introduces optical soliton control in micro- and nanoring resonator systems. It describes how the ring resonator systems can be optimized as optical tweezers for photodetection by controlling the input power, ring radii and coupling coefficients of the systems. Numerous arrangements and configurations of micro and nanoring resonator systems are explained. The analytical formulation and optical transfer function for each model and the interaction of the optical signals in the systems are discussed. This book shows that the models designed are able to control the dynamical behaviour of generated signals.

Simulation of the Sea Surface for Remote Sensing (Springer Oceanography)

by Alexander Zapevalov Konstantin Pokazeev Tatiana Chaplina

This book considers the formation of the signal reflected from the sea surface when sensing in the radio and optical range. Currently, remote sensing from space is the main source of information about the processes taking place in the atmosphere and ocean. The correct interpretation of remote sensing data requires detailed information about the rough surface that forms the reflected signal. The first three chapters describe the statistical and spatial-temporal characteristics of the sea surface, focusing on the effects associated with the nonlinearity of sea surface waves. The analysis makes extensive use of data obtained by the authors on a stationary oceanographic platform located on the Black sea. In the next seven chapters, the authors analyze how the nonlinearity of waves affects the formation of a signal reflected from the sea surface.This book is geared for advanced level research in the general subject area of remote sensing and modeling as they apply to the coastal marine environment. It is of value to scientists and engineers involved in the development of methods and instruments of remote sensing, analysis and interpretation of data. It is useful for students who have decided to devote themselves to the study of the oceans.

Simulation of Thermoelastic Behaviour of Spacecraft Structures: Fundamentals and Recommendations (Springer Aerospace Technology)

by Simon Appel Jaap Wijker

This book provides recommendations for thermal and structural modelling of spacecraft structures for predicting thermoelastic responses. It touches upon the related aspects of the finite element and thermal lumped parameter method. A mix of theoretical and practical examples supports the modelling guidelines. Starting from the system needs of instruments of spacecraft, the reader is supported with the development of the practical requirements for the joint development of the thermal and structural models. It provides points of attention and suggestions to check the quality of the models.The temperature mapping problem, typical for spacecraft thermoelastic analysis, is addressed. The principles of various temperature mapping methods are presented. The prescribed average temperature method, co-developed by the authors, is discussed in detail together with its spin-off to provide high quality conductors for thermal models. The book concludes with the discussion of the application of uncertainty assessment methods. The thermoelastic analysis chain is computationally expensive. Therefore, the 2k+1 point estimate method of Rosenblueth is presented as an alternative for the Monte Carlo Simuation method, bringing stochastic uncertainty analysis in reach for large thermoelastic problems.

Simulation of Transport in Nanodevices

by François Triozon Philippe Dollfus

Linear current-voltage pattern, has been and continues to be the basis for characterizing, evaluating performance, and designing integrated circuits, but is shown not to hold its supremacy as channel lengths are being scaled down. In a nanoscale circuit with reduced dimensionality in one or more of the three Cartesian directions, quantum effects transform the carrier statistics. In the high electric field, the collision free ballistic transform is predicted, while in low electric field the transport remains predominantly scattering-limited. In a micro/nano-circuit, even a low logic voltage of 1 V is above the critical voltage triggering nonohmic behavior that results in ballistic current saturation. A quantum emission may lower this ballistic velocity.

Simulation on Hydration of Tricalcium Silicate in Cement Clinker

by Dejian Shen Xin Wang

This book is written based on authors' research on cement hydration during the past decade. It establishes simulation model to evaluate the influence of crystal defects on the dissolution of tricalcium silicate and morphology change of particles and explores the hydration kinetics and microstructure development of tricalcium silicate under the mixed control of dissolution, diffusion, as well as boundary nucleation and growth. It also provides a theoretical basis for regulating the microstructure and performance of cement-based materials. It is designed as a reference work for professionals or practitioners and as a textbook for undergraduates or postgraduates. This book provides valuable knowledge and useful methods that can be applied in the field of cement hydration.

Simulation Systems

by George W. Zobrist

Simulation Systems expolres a wide spectrum of topics including simulation software, logic simulation, query-driven simulation, multi-computer simulation and manufacturing simulation. Although such papers are presented in Journals and conference proceedings it is difficult to find a single source where the foremost papers are presented. Contributio

Simulation Technologies in Networking and Communications: Selecting the Best Tool for the Test

by Al-Sakib Khan Pathan Muhammad Mostafa Monowar Shafiullah Khan

Simulation is a widely used mechanism for validating the theoretical model of networking or communication systems. Although the claims made based on simulations are considered to be reliable, how reliable they really are is best determined with real-world implementation trials. This book addresses various issues covering different mechanisms related to simulation technologies in networking and communications fields. Focusing on the practice of simulation testing instead of the theory, it reviews and evaluates popular simulation modeling tools and recommends the best tools for specific tests.

Simulation Tools and Methods for Supercritical Carbon Dioxide Radial Inflow Turbine: Development and Application on Open-Source Code

by Jianhui Qi

To protect the Earth, China has launched its target of peaking carbon dioxide emissions by 2030, and achieving carbon neutrality by 2060 , which greatly encourages the use and development of renewable energy. Supercritical CO2 power cycle is a promising technology and the radial inflow turbine is the most important component of it, whose design and optimisation are considered as great challenges. This book introduces simulation tools and methods for supercritical CO2 radial inflow turbine, including a high fidelity quasi-one-dimensional design procedure, a non-ideal compressible fluid dynamics Riemann solver within open-source CFD software OpenFOAM framework, and a multi-objective Nelder–Mead geometry optimiser. Enhanced one-dimensional loss models are presented for providing a new insight towards the preliminary design of the supercritical CO2 radial inflow turbine. Since the flow phenomena within the blade channels are complex, involving fluid flow, shock wave transmission and boundary layer separation, only employing the ideal gas model is inadequate to predict the performance of the turbine. Thus, a non-ideal compressible fluid dynamics Riemann solver based on OpenFOAM library is developed. This book addresses the issues related to the turbine design and blade optimization and provides leading techniques. Hence, this book is of great value for the readers working on the supercritical CO2 radial inflow turbine and understanding the knowledge of CFD and turbomachinery.

Simulation Tools for Predicting Daylighting Conditions in Buildings (Digital Innovations in Architecture, Engineering and Construction)

by Erika Dolníková

This book delves into the underexplored realm of daylight comfort in industrial structures, providing real measured data and insights supported by advanced simulations using the RADIANCE program. It highlights the vital role of daylight in human well-being and sustainable building design, offering a comprehensive analysis of how daylighting strategies and green technologies can reduce carbon footprints. With a focus on practical applications, the book guides designers in using simulation tools to predict and enhance indoor daylight environments, ensuring comfort and efficiency from design to completion.

Simulation Training: Fundamentals and Applications

by Philippe Fauquet-Alekhine Nane Pehuet

Drawing on decades of industrial experience, this insightful and practical guide uses case studies and an interdisciplinary perspective to explain the fundamentals of simulation training to improve performance of high-risk professional activities. It seeks to identify those conditions under which simulation training has been shown to improve professional practice while employing extensive real examples. Simulation Training: Fundamentals and Application helps readers to develop their own synthesis of the simulation learning method and to use such training to enhance their skills and performance. Case studies demonstrate five specific theatres of professional practice - the nuclear-power industry, aeronautics, surgery, anesthesia and metallurgy - and then detailed analysis highlights the common factors and key results. The author's background as a Human Factors Consultant, Physicist and Physiologist has enriched studies of humans in work situations, work organization and management and he has also been involved in pedagogical conception of experimental training on simulators based on his experience as a safety expert on nuclear power plant. The book is useful to practitioners, researchers and students, both in industry and in university. It is clearly cross disciplinary as it presents and discusses applications in engineering, professional practice (airline pilots) and medicine.

Simulations and Optical Diagnostics for Internal Combustion Engines: Current Status and Way Forward (Energy, Environment, and Sustainability)

by Akhilendra Pratap Singh Pravesh Chandra Shukla Joonsik Hwang Avinash Kumar Agarwal

This book focuses on combustion simulations and optical diagnostics techniques, which are currently used in internal combustion engines. The book covers a variety of simulation techniques, including in-cylinder combustion, numerical investigations of fuel spray, and effects of different fuels and engine technologies. The book includes chapters focused on alternative fuels such as DEE, biomass, alcohols, etc. It provides valuable information about alternative fuel utilization in IC engines. Use of combustion simulations and optical techniques in advanced techniques such as microwave-assisted plasma ignition, laser ignition, etc. are few other important aspects of this book. The book will serve as a valuable resource for academic researchers and professional automotive engineers alike.

Simulations for Design and Manufacturing: Select Papers From Aimtdr 2016 (Lecture Notes On Multidisciplinary Industrial Engineering)

by Ravi Kant Uday S. Dixit

This book focuses on numerical simulations of manufacturing processes, discussing the use of numerical simulation techniques for design and analysis of the components and the manufacturing systems. Experimental studies on manufacturing processes are costly, time consuming and limited to the facilities available. Numerical simulations can help study the process at a faster rate and for a wide range of process conditions. They also provide good prediction accuracy and deeper insights into the process. The simulation models do not require any pre-simulation, experimental or analytical results, making them highly suitable and widely used for the reliable prediction of process outcomes. The book is based on selected proceedings of AIMTDR 2016. The chapters discuss topics relating to various simulation techniques, such as computational fluid dynamics, heat flow, thermo-mechanical analysis, molecular dynamics, multibody dynamic analysis, and operational modal analysis. These simulation techniques are used to: 1) design the components, 2) to investigate the effect of critical process parameters on the process outcome, 3) to explore the physics of the process, 4) to analyse the feasibility of the process or design, and 5) to optimize the process. A wide range of advanced manufacturing processes are covered, including friction stir welding, electro-discharge machining, electro-chemical machining, magnetic pulse welding, milling with MQL (minimum quantity lubrication), electromagnetic cladding, abrasive flow machining, incremental sheet forming, ultrasonic assisted turning, TIG welding, and laser sintering. This book will be useful to researchers and professional engineers alike.

Simulations in Bulk Solids Handling: Applications of DEM and other Methods

by Don McGlinchey

Simulations in Bulk Solids Handling Valuable resource for engineers and professionals dealing with bulk granular or powdered materials across industries using Discrete Element Methods (DEM) In many traditional university engineering programmes, no matter whether undergraduate or postgraduate, the behavior of granular materials is not covered in depth or at all. This omission leaves recent engineering graduates with little formal education in the major industrial area of bulk solids handling. This book teaches young professionals and engineers to find appropriate solutions for handling granular and powdered materials. It also provides valuable information for experienced engineers to gain an understanding and appreciation of the most significant simulation methods–DEM chief amongst them. For any student or professional involved with bulk solids handling, this book is a key resource to understand the most efficient and effective stimulation methods that are available today. Its comprehensive overview of the topic allows for upcoming professionals to ensure they have adequate knowledge in the field and for experienced professionals to improve their skills and processes.

Simulations in Nanobiotechnology

by Kilho Eom

Until the late 20th century, computational studies of biomolecules and nanomaterials had considered the two subjects separately. A thorough presentation of state-of-the-art simulations for studying the nanoscale behavior of materials, Simulations in Nanobiotechnology discusses computational simulations of biomolecules and nanomaterials together. Th

Simulator-based Human Factors Studies Across 25 Years

by Ann Britt Skjerve Andreas Bye

The Halden Man-Machine Laboratory (HAMMLAB) has been at the heart of human factors research at the OECD Halden Reactor Project (HRP). The HRP is sponsored by a group of national organizations, representing nuclear power plant regulators, utilities, and research institutions. The HRP is hosted by the Institute for Energy Technology (IFE) in Halden, Norway. HAMMLAB comprises three full-scale nuclear power plant control room research simulators. The simulator studies performed in HAMMLAB have traditionally been experimental in nature. In a simulator it is possible to study events as they unfold in real time, in a highly realistic operational environment under partially controlled conditions. This means that a wide range of human factors issues, which would be impossible or highly impracticable to study in real-life settings, can thus be addressed in HAMMLAB. Simulator-based Human Factors Studies Across 25 Years celebrates the twenty-fifth anniversary of HAMMLAB by reviewing the human factors studies performed in HAMMLAB across this time-span. A range of human factors issues have been addressed, including: * human-system interfaces; * alarm systems; * computerized procedures; * human-automation interaction; * staffing, teamwork and human reliability. The aim of HAMMLAB studies has always been the same: to generate knowledge for solving current and future challenges in nuclear power plant operation to contribute to safety. The outcomes of HAMMLAB studies have been used to support design and assessment of nuclear power plant control rooms.

Simulators for Transportation Human Factors: Research and Practice (The Human Factors of Simulation and Assessment Series)

by Mark Young Michael Lenné

Simulation continues to be a growth area in transportation human factors. From empirical studies in the laboratory to the latest training techniques in the field, simulators offer myriad benefits for the experimenter and the practitioner. This book draws together current trends in research and training simulators for the road, rail, air and sea sectors to inform the reader how to maximize both validity and cost-effectiveness in each case. Simulators for Transportation Human Factors provides a valuable resource for both researchers and practitioners in transportation human factors on the use of simulators, giving readers concrete examples and case studies of how simulators have been developed and used in empirical research as well as training applications. It offers useful and usable information on the functional requirements of simulators without the need for any background knowledge on the technical aspects, focusing on the state of the art of research and applications in transport simulators rather than the state of the art of simulation technology. The book covers simulators in operational terms instead of task simulation/modelling and provides a useful balance between a bottom-up, academic approach and a top-down, practical perspective.

Simultaneous Catalytic Removal of Diesel Soot and NOx (Energy and Environment Research in China)

by Wenfeng Shangguan Guchu Zou Zhi Jiang

This book not only explores catalysis processes in redox reactions but also proposes a potential after-treatment strategy. Summarizing the authors’ major works, it offers a guidebook for those working on environmental and industrial catalysis. It presents insights into reaction kinetics in a variety of materials and analyzes the external conditions influencing the reaction. As such it is of particular interest to engineers and scientists in the field of material chemistry, chemical engineering and automobile industry. With novel images and illustrations, it provides a new perspective for interpreting soot abatement material and understanding the reaction process and inspires scientists to design new catalysts with moderate redox capacity.

Simultaneous Mass Transfer and Chemical Reactions in Engineering Science

by Bertram K. Chan

Simultaneous Mass Transfer and Chemical Reactions in Engineering Science A comprehensive look at the basic science of diffusional process and mass transfer Mass transfer as a principle is an essential part of numerous unit operations in biomolecular, chemical, and process engineering; crystallization, distillation, and membrane separation processes, for example, use this important method. Given this significance – particularly in engineering design where these processes occur – understanding the design and analysis of such unit operations must begin with a basic understanding of how simultaneous mass transfer and the chemical reactions that influence these occurrences. It is also vital to be aware of the most up-to-date technologies for analyzing and predicting the phenomena. Given the significance of this process, Simultaneous Mass Transfer and Chemical Reactions in Engineering Science is an important resource as it introduces the reader to the complex subject of simultaneous mass transfer with biochemical and chemical reactions and gives them the tools to develop an applicable design. Analyzing the systems of simultaneous mass transfer and reactions is at the core of this book, as all known design approaches are carefully examined and compared. The volume also provides the reader with a working knowledge of the latest technologies – with a special focus on the open-sourced computer programming language R – and how these tools are an essential resource in quantitative assessment in analysis models. Simultaneous Mass Transfer and Chemical Reactions in Engineering Science provides a working knowledge of the latest information on simultaneous mass transfer and reactions by focusing on the analysis of this process, as well as discussing the existence and distinctive quality of the solutions to the Simultaneous Mass Transfer and Chemical Reactions in Engineering Science readers will also find: A theoretical basis of each design model that is carefully stated, compared, and assessed Carefully developed and established Existence and Uniqueness Theorems for a general design model Comprehensive coverage of how the programming language R may be used to analyze models Numerous examples and case studies that provide a working knowledge of simultaneous mass transfer and reactions Simultaneous Mass Transfer and Chemical Reactions in Engineering Science is a useful reference for students in chemical engineering, biotechnology, or chemistry, as well as professional process and chemical engineers.

Simultaneous Sulfate Reduction and Metal Precipitation in an Inverse Fluidized Bed Reactor: UNESCO-IHE PhD Thesis

by Denys Kristalia Gómez

Industrial activities like textile processing and mining are typical sources of heavy metal-rich wastewaters. The sulfate reducing process has become an attractive method for the production of sulfide to precipitate metals since most of these streams also contain sulfate, which is the electron acceptor and, in less common cases, chemical oxygen demand which is the electron donor of sulfate reducing bacteria. The inverse fluidized bed (IFB) reactor is a system for the production of biogenic sulfide and metal precipitation in the same unit due to its configuration: the biomass floats on top of the reactor, whereas metal sulfide precipitates settle and thus can be recovered at the bottom. The main objective of this thesis was to elucidate the factors affecting simultaneous sulfate reduction and precipitation of heavy metals in an IFB reactor in order to optimize the metal recovery from wastewaters such as acid mine drainage. Therefore, this thesis focused on varying different operational conditions to study their effect on the solid-liquid separation and purity of the metal sulfide precipitates as well as on their effect on the sulfate reducing process. Furthermore, one chapter was focused on the study of strategies for sulfide control in the IFB reactor. In addition, recommendations for further research to improve the recovery of the metal sulfides in bioreactors are given.

Simultaneous Systems of Differential Equations and Multi-Dimensional Vibrations (Mathematics and Physics for Science and Technology)

by Luis Manuel Braga da Costa Campos

Simultaneous Differential Equations and Multi-Dimensional Vibrations is the fourth book within Ordinary Differential Equations with Applications to Trajectories and Vibrations, Six-volume Set. As a set, they are the fourth volume in the series Mathematics and Physics Applied to Science and Technology. This fourth book consists of two chapters (chapters 7 and 8 of the set). The first chapter concerns simultaneous systems of ordinary differential equations and focuses mostly on the cases that have a matrix of characteristic polynomials, namely linear systems with constant or homogeneous power coefficients. The method of the matrix of characteristic polynomials also applies to simultaneous systems of linear finite difference equations with constant coefficients. The second chapter considers linear multi-dimensional oscillators with any number of degrees of freedom including damping, forcing, and multiple resonance. The discrete oscillators may be extended from a finite number of degrees-of-freedom to infinite chains. The continuous oscillators correspond to waves in homogeneous or inhomogeneous media, including elastic, acoustic, electromagnetic, and water surface waves. The combination of propagation and dissipation leads to the equations of mathematical physics. Presents simultaneous systems of ordinary differential equations and their elimination for a single ordinary differential equation Includes cases with a matrix of characteristic polynomials, including simultaneous systems of linear differential and finite difference equations with constant coefficients Covers multi-dimensional oscillators with damping and forcing, including modal decomposition, natural frequencies and coordinates, and multiple resonance Discusses waves in inhomogeneous media, such as elastic, electromagnetic, acoustic, and water waves Includes solutions of partial differential equations of mathematical physics by separation of variables leading to ordinary differential equations

Simultaneously Transmitting and Reflecting Surfaces for Wireless Communications (Wireless Networks)

by Yuanwei Liu Xidong Mu Jiaqi Xu Junshan Zhang

This book begins with discussing the fundamentals of Simultaneously Transmitting and Reflecting Surfaces (STARS) from the electromagnetic (EM) and communication perspectives. The basic signal and channel models for employing STARS in wireless communications is introduced as well. Then, the different categories and possible hardware implementation of STARS are highlighted. Next, the authors focus on attention to the STARS-aided wireless communications. The authors provide a comprehensive performance analysis of STARS with the outage probability, diversity gain and power scaling laws. Moreover, the operating protocols and corresponding beamforming design of STARS are discussed under different phase-shift models. As a further advance, the application of machine learning tools in STAR-aided wireless communications is introduced for addressing the beamforming design and resource allocation problems. The novel STARS-aided integrated sensing and communications (ISAC) in future wireless networks are also discussed with several case studies. Within this book, readers will find an extensive exploration of the STARS concept. The content encompasses a thorough survey of STARS research, covering principles, implementation, performance evaluation and applications. By presenting a comprehensive review of the STARS family, this book serves as a valuable resource for gaining insight into the complete pipeline of STARS research. Finally, the authors conclude the book by highlighting several future research directions for STARS. This book targets graduate, undergraduate, and postgraduate students as well as researchers working in wireless communications. Wireless communication engineers in industry and government will also want to purchase this book.

Sincerely, Emerson: A Girl, Her Letter, and the Helpers All Around Us

by Emerson Weber

One tiny act of kindness can have a huge impact. And in this heartwarming, hopeful, absolutely true story, a simple letter does just that.A true story that quickly went viral, this is now a timely, extraordinary picture book. Sincerely, Emerson follows eleven-year-old Emerson Weber as she writes a letter of thanks to her postal carrier, Doug, and creates a nationwide outpouring of love.This is a story of gratitude, hope, and recognition: for all the essential helpers we see everyday, and all those who go unseen. Perfect for sharing alongside such favorites as Pat Zietlow Miller and Jen Hill's Be Kind and Matt de la Peña and Loren Long's Love.There are lots of ways to help the world go round:Some people collect the trash. Some stock grocery shelves. Some drive buses and trains. Some help people who are sick. Some deliver our mail. And some people write letters.

The Singapore Water Story: Sustainable Development in an Urban City State

by Asit K. Biswas Cecilia Tortajada Yugal Kishore Joshi

Singapore´s journey during the past 45 years is an outstanding example that, in spite of multiple hardships, pragmatic policies, clear visions, long-term planning, forward-looking strategies and political will, as well as a relentless urge to improve, can result in strong foundations for sustainable development. This book describes the journey of Singapore´s development and the fundamental role that water has had in shaping it. What makes this case so unique is that the quest for self-sufficiency in terms of water availability in a fast-changing urban context has been crucial to the way development policies and agendas have been planned throughout the years. The authors analyse plans, policies, institutions, laws and regulations, water demand and water supply strategies, water quality and water conservation considerations, partnerships and importance of the media. They assess overall how all these issues have evolved in response to the dynamic needs of the city-state. The study of Singapore shows how a dynamic society can address development without losing its focus on the environment. In the city-state, environmental concerns in general, and water concerns in particular, have played a major role in its transformation from a third word to a first world country. How and why this transformation took place is the main focus of this authoritative book.

Single and Cross-Layer Mimo Techniques for Imt-Advanced (River Publishers Series In Communications Ser.)

by Filippo Meucci

In the last two decades, the wireless arena has witnessed the emergence of an astonishing number of technologies which play a part in the definition of new wireless systems. Driven by the pressing capacity demand, the research community has developed several technological enablers. Fundamental technological building blocks that will be part of wireless systems in the near-future definitely include: Orthogonal Frequency Division Multiplexing (OFDM) modulation at the physical (PHY) layer, Multiple Input Multiple.Output (MIMO) systems, and a cross-layer (CL) stack design. While the benefits of OFDM have been recognized for several years, the real capacity improvement of MIMO antennae is still being debated today. As to the lastpoint, even if opportunities for CL have been pointed out for a long time, the impact on the actual legacy systems has not been noticeable, as investors are hesitant to implement the inherent design paradigm shift.Single and Cross-Layer MIMO Techniques for IMT-Advanced will present some advanced MIMO techniques where adaptivity, cross-layer approach, and MIMO antennae are analyzed together to show a deep impact on the sum-capacityachievable over the wireless link.The introduction presents the functional requirements for IMT-A candidate systems and the relation between IEEE802.16 and LTE wireless access networks. Then, in the first part, adaptive strategies are analyzedseparately at the PHY and Medium Access Control (MAC) layers. The second part presents an evolution of the previous approach, providing a cross-layer MIMO-ARQ protocol, where adaptive MIMO schemes, namely SpatialMultiplexing (SM) and STBC Alamouti, are used with ARQ protocol. A Multiple User (MU) network is served in DownLink (DL) with a Round Robin (RR) scheduler; the design is ready to include more advanced schedulers. The ARQstate machine at the MAC layer is aware of per-antenna ARQ. The interaction between the ARQ and the PHY layer, with a per-antenna ACK, allows resource exploitation to increase with per-antenna ACKs, shifting from MIMO Signal Processing Gain to MIMO Protocol Gain with no need for Channel State Information (CSI) feedback. The absence of CSI feedback at the PHY layer is an important characteristic of the proposedMIMO-ARQ cross-layer designs since MIMO CSI feedback (when feasible) drastically reduces the network efficiency.The added degrees of freedom offered by MIMO transmissions can make the difference if correctly exploited both at the physical and medium access layers, in particular for overcoming the problem of low MIMO channel ranks.The advantages of the paradigm shift from signal processing gain to protocol gain - together with the modifications to be applied at the classical protocol stack - are discussed in the final chapter.

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