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Method of Moments for 2D Scattering Problems

Author : Christophe Bourlier

Publisher : John Wiley & Sons

Page : 122 pages

File Size : 21,16 MB

Release : 2013-08-05

Category : Computers

ISBN : 1118648684

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Book Description

Electromagnetic wave scattering from randomly rough surfaces in the presence of scatterers is an active, interdisciplinary area of research with myriad practical applications in fields such as optics, acoustics, geoscience and remote sensing. In this book, the Method of Moments (MoM) is applied to compute the field scattered by scatterers such as canonical objects (cylinder or plate) or a randomly rough surface, and also by an object above or below a random rough surface. Since the problem is considered to be 2D, the integral equations (IEs) are scalar and only the TE (transverse electric) and TM (transverse magnetic) polarizations are addressed (no cross-polarizations occur). In Chapter 1, the MoM is applied to convert the IEs into a linear system, while Chapter 2 compares the MoM with the exact solution of the field scattered by a cylinder in free space, and with the Physical Optics (PO) approximation for the scattering from a plate in free space. Chapter 3 presents numerical results, obtained from the MoM, of the coherent and incoherent intensities scattered by a random rough surface and an object below a random rough surface. The final chapter presents the same results as in Chapter 3, but for an object above a random rough surface. In these last two chapters, the coupling between the two scatterers is also studied in detail by inverting the impedance matrix by blocks. Contents 1. Integral Equations for a Single Scatterer: Method of Moments and Rough Surfaces. 2. Validation of the Method of Moments for a Single Scatterer. 3. Scattering from Two Illuminated Scatterers. 4. Scattering from Two Scatterers Where Only One is Illuminated. Appendix. Matlab Codes. About the Authors Christophe Bourlier works at the IETR (Institut d’Electronique et de Télécommunications de Rennes) laboratory at Polytech Nantes (University of Nantes, France) as well as being a Researcher at the French National Center for Scientific Research (CNRS) on electromagnetic wave scattering from rough surfaces and objects for remote sensing applications and radar signatures. He is the author of more than 160 journal articles and conference papers. Nicolas Pinel is currently working as a Research Engineer at the IETR laboratory at Polytech Nantes and is about to join Alyotech Technologies in Rennes, France. His research interests are in the areas of radar and optical remote sensing, scattering and propagation. In particular, he works on asymptotic methods of electromagnetic wave scattering from random rough surfaces and layers. Gildas Kubické is in charge of the “Expertise in electroMagnetism and Computation” (EMC) laboratory at the DGA (Direction Générale de l’Armement), French Ministry of Defense, where he works in the field of radar signatures and electromagnetic stealth. His research interests include electromagnetic scattering and radar cross-section modeling.



Infrared Spectroscopy of Triatomics for Space Observation

Author : Pierre-Richard Dahoo

Publisher : John Wiley & Sons

Page : 241 pages

File Size : 41,75 MB

Release : 2019-01-03

Category : Science

ISBN : 1119579244

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Book Description

This book is dedicated to the application of the different theoretical models described in Volume 1 to identify the near-, mid- and far-infrared spectra of linear and nonlinear triatomic molecules in gaseous phase or subjected to environmental constraints, useful for the study of environmental sciences, planetology and astrophysics. The Van Vleck contact transformation method, described in Volume 1, is applied in the calculation and analysis of IR transitions between vibration–rotation energy levels. The extended Lakhlifi–Dahoo substitution model is used in the framework of Liouville’s formalism and the line profiles of triatomic molecules and their isotopologues subjected to environmental constraints are calculated by applying the cumulant expansion. The applications presented in this book show how interactions at the molecular level modify the infrared spectra of triatomics trapped in a nano-cage (substitution site of a rare gas matrix, clathrate, fullerene, zeolite) or adsorbed on a surface, and how these interactions may be used to identify the characteristics of the perturbing environment.



Design Constraints for NFC Devices

Author : Dominique Paret

Publisher : John Wiley & Sons

Page : 224 pages

File Size : 14,71 MB

Release : 2016-04-11

Category : Technology & Engineering

ISBN : 1848218842

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Book Description

Near field communication (NFC) can appear to be a simple intuitive technology for exchanging data between close devices. In reality, these contactless structures that combine components and antennas must respect important and specific working constraints. Illustrated by a number of detailed technological examples, this book discusses the multiple normative (ISO, CEN, NFC Forum, EMVCo, etc.) and regulatory (ERC, FCC, ETSI, radiofrequency, private and ecological pollution, etc.) constraints, as well as the applied, typological, functional, structural, environmental or interoperability constraints that a NFC device might face. Design Constraints for NFC Devices also presents techniques that enable us to free ourselves from the technological constraints of current NFC operations encountered in banking, public transport, administration, automotive, industrial, communicating object and Internet of Things applications.



The Wave Concept in Electromagnetism and Circuits

Author : Henri Baudrand

Publisher : John Wiley & Sons

Page : 221 pages

File Size : 29,57 MB

Release : 2016-08-17

Category : Science

ISBN : 1119347599

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Book Description

The Wave Concept Iterative Procedure (WCIP) method has found an increasing number of users within electromagnetic theory and applications to planar circuits, antennas and diffraction problems. This book introduces in detail this new formulation of integral methods, based on the use of a wave concept with two bounded operators, and applications in a variety of domains in electromagnetics. This approach presents a number of benefits over other integral methods, including overcoming the problem of singularity, and reduced computing time. Through the presentation of mathematical equations to characterize studied structures and explanation of the curves obtained, via validated examples, the authors provide a thorough background to electromagnetism as well as a professional reference to students and researchers.



Synthesizers and Subtractive Synthesis 1

Author : Jean-Michel Réveillac

Publisher : John Wiley & Sons

Page : 292 pages

File Size : 34,61 MB

Release : 2024-02-21

Category : Technology & Engineering

ISBN : 1394276710

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Book Description

Subtractive sound synthesis has been one of the most widely used techniques in electronic music and for many analog synthesizers since the early 1960s. It is based on a simple principle, but its operation remains complex, involving many parameters. It can be enriched by a variety of effects that give the sound its authenticity. It does not just imitate musical instruments, but can also transcribe noises present in natural soundscapes, or generate entirely synthetic sounds. Synthesizers and Subtractive Synthesis 1 presents the theoretical basis of a sound phenomenon, the different types of synthesis, the components that are required and present in synthesizers, the working environment specific to the study of subtractive synthesis, and the hardware and software available. After reading the various chapters of this book, readers will have a clear vision of the tools and actions required to grasp the world of subtractive sound.



Radio-Frequency Human Exposure Assessment

Author : Joe Wiart

Publisher : John Wiley & Sons

Page : 157 pages

File Size : 42,81 MB

Release : 2016-03-03

Category : Computers

ISBN : 1119285151

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Book Description

Nowadays approximately 6 billion people use a mobile phone and they now take a central position within our daily lives. The 1990s saw a tremendous increase in the use of wireless systems and the democratization of this means of communication. To allow the communication of millions of phones, computers and, more recently, tablets to be connected, millions of access points and base station antennas have been extensively deployed. Small cells and the Internet of Things with the billions of connected objects will reinforce this trend. This growing use of wireless communications has been accompanied by a perception of risk to the public from exposure to radio frequency (RF) electromagnetic field (EMF). To address this concern, biomedical research has been conducted. It has also been important to develop and improve dosimetry methods and protocols that could be used to evaluate EMF exposure and check compliance with health limits. To achieve this, much effort has was made in the 1990s and 2000s. Experimental and numerical methods, including statistical methods, have been developed. This book provides an overview and description of the basic and advanced methods that have been developed for human RF exposure assessment. It covers experimental, numerical, deterministic and stochastic methods.



Secure Connected Objects

Author : Dominique Paret

Publisher : John Wiley & Sons

Page : 320 pages

File Size : 26,68 MB

Release : 2017-05-24

Category : Computers

ISBN : 1119426480

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Book Description

In this book, the authors focus on the concrete aspects of IoT (Internet of Things): the daily operation, on the ground, of this domain, including concrete and detailed discussion of the designs, applications and realizations of Secure Connected Things and IoT. As experts in the development of RFID and IoT technologies, the authors offer the reader a highly technical discussion of these topics, including the many approaches (technical, security, safety, ergonomic, economic, normative, regulations, etc.) involved in Secure Connected Objects projects. This book is written both for readers wishing to familiarize themselves with the complex issues surrounding networking objects and for those who design these connective "things".



Generalized Multipole Techniques for Electromagnetic and Light Scattering

Author : T. Wriedt

Publisher : Elsevier

Page : 273 pages

File Size : 13,94 MB

Release : 1999-12-01

Category : Technology & Engineering

ISBN : 0080532373

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Book Description

This book is an edited volume of nine papers covering the different variants of the generalized multipole techniques (GMT). The papers were presented at the recent 3rd Workshop on Electromagnetics and Light Scattering - Theory and Applications, which focused on current GMT methods. These include the multiple multipole method (MMP), the discrete sources method (DSM), Yasuura's method, method of auxiliary sources and null-field method with discrete sources. Each paper presents a full theoretical description as well as some applications of the method in electrical engineering and optics. It also includes both 2D and 3D methods and other applications developed in the former Soviet Union and Japan.



Electromagnetic Scattering using the Iterative Multi-Region Technique

Author : Mohamed H. Al Sharkawy

Publisher : Springer Nature

Page : 99 pages

File Size : 33,27 MB

Release : 2022-06-01

Category : Technology & Engineering

ISBN : 3031017021

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Book Description

In this work, an iterative approach using the finite difference frequency domain method is presented to solve the problem of scattering from large-scale electromagnetic structures. The idea of the proposed iterative approach is to divide one computational domain into smaller subregions and solve each subregion separately. Then the subregion solutions are combined iteratively to obtain a solution for the complete domain. As a result, a considerable reduction in the computation time and memory is achieved. This procedure is referred to as the iterative multiregion (IMR) technique. Different enhancement procedures are investigated and introduced toward the construction of this technique. These procedures are the following: 1) a hybrid technique combining the IMR technique and a method of moment technique is found to be efficient in producing accurate results with a remarkable computer memory saving; 2) the IMR technique is implemented on a parallel platform that led to a tremendous computational time saving; 3) together, the multigrid technique and the incomplete lower and upper preconditioner are used with the IMR technique to speed up the convergence rate of the final solution, which reduces the total computational time. Thus, the proposed iterative technique, in conjunction with the enhancement procedures, introduces a novel approach to solving large open-boundary electromagnetic problems including unconnected objects in an efficient and robust way. Contents: Basics of the FDFD Method / IMR Technique for Large-Scale Electromagnetic Scattering Problems: 3D Case / IMR Technique for Large-Scale Electromagnetic Scattering Problems: 2D Case / The IMR Algorithm Using a Hybrid FDFD and Method of Moments Technique / Parallelization of the Iterative Multiregion Technique / Combined Multigrid Technique and IMR Algorithm / Concluding Remarks / Appendices



Electromagnetic Wave Scattering from Random Rough Surfaces

Author : Nicolas Pinel

Publisher : John Wiley & Sons

Page : 122 pages

File Size : 39,6 MB

Release : 2013-12-02

Category : Science

ISBN : 1118579461

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Book Description

Electromagnetic wave scattering from random rough surfaces is an active, interdisciplinary area of research with myriad practical applications in fields such as optics, acoustics, geoscience and remote sensing. Focusing on the case of random rough surfaces, this book presents classical asymptotic models used to describe electromagnetic wave scattering. The authors begin by outlining the basic concepts relevant to the topic before moving on to look at the derivation of the scattered field under asymptotic models, based on the Kirchhoff-tangent plane, in order to calculate both the scattered field and the statistical average intensity. More elaborated asymptotic models are also described for dealing with specific cases, and numerical results are presented to illustrate these models. Comparisons with a reference numerical method are made to confirm and refine the theoretical validity domains. The final chapter derives the expressions of the scattering intensities of random rough surfaces under the asymptotic models. Its expressions are given for their incoherent contributions, from statistical calculations. These results are then compared with numerical computations using a Monte-Carlo process, as well as with experimental models, for sea surface backscattering. Contents 1. Electromagnetic Wave Scattering from Random Rough Surfaces: Basics. 2. Derivation of the Scattered Field under Asymptotic Models. 3. Derivation of the Normalized Radar Cross-Section under Asymptotic Models. APPENDIX 1. Far-Field Scattered Fields under the Method of Stationary Phase. APPENDIX 2. Calculation of the Scattering Coefficients under the GO for 3D Problems. About the Authors Nicolas Pinel worked as a Research Engineer at the IETR (Institut d’Electronique et de Télécommunications de Rennes) laboratory at Polytech Nantes (University of Nantes, France) before joining Alyotech Technologies in Rennes, France, in July 2013. His research interests are in the areas of radar and optical remote sensing, scattering and propagation. In particular, he works on asymptotic methods of electromagnetic wave scattering from random rough surfaces and layers. Christophe Bourlier works at the IETR (Institut d’Electronique et de Télécommunications de Rennes) laboratory at Polytech Nantes (University of Nantes, France) and is also a Researcher at the French National Center for Scientific Research (CNRS) on electromagnetic wave scattering from rough surfaces and objects for remote sensing applications and radar signatures. He is the author of more than 160 journal articles and conference papers.