Download or read book The Transmission line Modeling TLM Method in Electromagnetics written by Christos Christopoulos and published by Morgan & Claypool Publishers. This book was released on 2006 with total page 133 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the topic in electromagnetics known as Transmission-Line Modeling or Matrix method-TLM. While it is written for engineering students at graduate and advanced undergraduate levels, it is also highly suitable for specialists in computational electromagnetics working in industry, who wish to become familiar with the topic. The main method of implementation of TLM is via the time-domain differential equations, however, this can also be via the frequency-domain differential equations. The emphasis in this book is on the time-domain TLM. Physical concepts are emphasized here before embarking onto mathematical development in order to provide simple, straightforward suggestions for the development of models that can then be readily programmed for further computations. Sections with strong mathematical flavors have been included where there are clear methodological advantages forming the basis for developing practical modeling tools. The book can be read at different depths depending on the background of the reader, and can be consulted as and when the need arises.
Download or read book The Transmission line Modeling Method written by Christos Christopoulos and published by Oxford University Press, USA. This book was released on 1995 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by renowned researcher Christos Christopoulos, this book covers a broad area of electromagnetics, including microwaves, antennas, radar cross-section, electromagnetic compatibility, and electromagnetic heating. In addition, you will find a clear explanation of modeling principles from lumped components through one-, two, and three-dimensional complex systems.
Download or read book The Transmission Line Modeling t L M Method In Electromagnetics written by Christos Christopoulos and published by . This book was released on 2006 with total page 101 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transmission Line Matrix TLM in Computational Mechanics written by Donard de Cogan and published by CRC Press. This book was released on 2005-11-01 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: The finite element method reigns as the dominant technique for modeling mechanical systems. Originally developed to model electromagnetic systems, the Transmission Line Matrix (TLM) method proves to match, and in some cases exceed, the effectiveness of finite elements for modeling several types of physical systems. Transmission Line Matrix in Compu
Download or read book Electromagnetic Analysis Using Transmission Line Variables written by Maurice Weiner and published by World Scientific. This book was released on 2001 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt: V. Boundary conditions and dispersion. 5.1. Dielectric-dielectric interface. Node coupling: nearest node and multi-coupled node approximations. 5.2. Nearest nodes for ID interface. 5.3. Nearest nodes at 2D interface. 5.4. Truncated cell and oblique interface. 5.5. Single index cell notation. 5.6. Simplified iteration neglecting the nearest node approximation. 5.7. Non-uniform dielectric. Use of cluster cells. Other boundary conditions. 5.8. Dielectric- open circuit interface. 5.9. Dielectric - conductor interface. 5.10. Input/output conditions. 5.11. Composite transmission line. 5.12. Determination of initial static field by TLM method. 5.13. Time varying source voltage and antenna simulation. Dispersion. 5.14. Dispersion sources. 5.15. Dispersion example. 5.16. Propagation velocity in terms of wave number. 5.17. Dispersive properties of node resistance. 5.18. Node resistance in terms of wave number. 5.19. Anomalous dispersion. Incorporation of dispersion into TLM formulation. 5.20. Dispersion approximations. 5.21. Outline of dispersion calculation using the TLM method. 5.22. One dimensional dispersion iteration. 5.23. Initial conditions with dispersion present. 5.24. Stability of initial profiles with dispersion present. 5.25. Replacement of non-uniform field in cell with effective uniform field -- VI. Cell discharge properties and integration of transport phenomena into the TLM matrix. 6.1. Charge transfer between cells. 6.2. Relationship between field and cell charge. 6.3. Dependence of conductivity on carrier properties. Integration of carrier transport using TLM notation. Changes in cell occupancy and its effect on TLM iteration. 6.4. General continuity equations. 6.5. Carrier generation due to light activation. 6.6. Carrier generation due to avalanching: identical hole and electron drift velocities. 6.7. Avalanching with differing hole and electron drift velocities. 6.8. Two step generation process. 6.9. Recombination. 6.10. Limitations of simple exponential recovery model. 6.11. Carrier drift. 6.12. Cell charge iteraction.equivalence of drift and inter-cell currents. 6.13. Carrier diffusion. 6.14. Frequency of transport iteration. 6.15. Total contribution to changes in carrier cell occupancy -- VII. Description of TLM iteration. 7.1. Specification of geometry. 7.2. Description of inputs and TLM iteration outline. 7.3. Output format. Output simulation data. 7.4. Conditions during simulation. 7.5. Behavior during charge-up.establishment of static field profile. 7.6. Node resistance R(n,m) during activation. 7.7. Output pulse when semiconductor is activated. 7.8. Node recovery and its effect on output pulse. 7.9. Steady state and transient field profiles. 7.10. Partial activation of nodes and effect on profiles and output. 7.11. Cell charge following recovery. 7.12. Role ofTLM waves at charged boundary. 7.13. Comparison of possible boundary conditions at the semiconductor/dielectric interface. 7.14. Simulation results for boundary with non-integral nearest nodes. 7.15. Comparison of output with and without matched input /output lines. 7.16. Simulation of plane wave effects. Effect of alternating input -- VIII. Spice solutions. 8.1. Photoconductive switch. 8.2. Traveling wave Marx generator. 8.3. Traveling Marx wave in a layered dielectric. 8.4. Simulation of a traveling Marx wave in a layered dielectric. Pulse transformation and generation using non-uniform transmission lines. 8.5. Use of cell chain to simulate pulse transformer. 8.6. Pulse transformer simulation results. 8.7. Pulse sources using non-uniform TLM lines (switch at output). 8.8. Radial pulse source (switch at output). 8.9. Pulse sources with gain (PFXL sources). Darlington pulser. 8.10. TLM formulation of Darlington pulser. 8.11. SPICE simulation of Lossy Darlington Pulser.
Download or read book Electromagnetic Analysis Using Transmission Line Variables Third Edition written by Weiner Maurice and published by World Scientific. This book was released on 2017-12-27 with total page 652 pages. Available in PDF, EPUB and Kindle. Book excerpt: This latest edition continues the evolution toward the ultimate realization of a new technique for solving electromagnetic propagation problems. The technique combines the classical and intuitive use of a transmission line matrix (TLM) while striving for consistency with the guideposts demanded by quantum mechanics and the essential structure of electromagnetic theory. The matrix then becomes a useful vehicle for examining both coherent and noncoherent electromagnetic waves. The goal is a mathematical tool capable of solving problems related to the propagation of transient, high-speed, complex waveforms containing both symmetric and plane wave components. For such waveforms, standard classical electromagnetic theory is unable to provide a truly accurate solution since it does not properly account for the correlations among the various TLM cells. The correlations among neighboring TLM cells allow the cell waves to sense one another and to collectively participate as a coherent wave. For arbitrary signals, e.g., complex, high speed, highly non-uniform signals, the correlation model must be placed on a firmer footing to insure the proper correlation strength based on the close adherence to quantum mechanical principles. The purpose of the Third Edition is to thereby improve the correlation model, and incorporate the model into the simulations. The simulation results thus obtained show great promise in describing the full range of electromagnetic phenomena. Wave divergence and diffraction simulations, employing both composite and shorter range correlation models, have been incorporated. The models employ correlation coefficients which may be linked with quantum mechanical parameters, thus providing a deeper understanding of coherent wave fronts. Contents: Introduction to Transmission Lines and Their Application to Electromagnetic PhenomenaNotation and Mapping of Physical PropertiesScattering EquationsCorrections for Plane Wave and Grid Anisotropy EffectsBoundary Conditions and DispersionCell Discharge Properties and Integration of Transport Phenomena into the Transmission Line MatrixDescription of TLM Iteration (includes Correlation/Decorrelation Effects)SPICE Solutions Readership: Graduate students and researchers in applied physics and electrical engineering. Keywords: Transmission Line Matrix;Electromagnetics;Plane Waves;Wave Correlations;Light Activated Semiconductor;Picosecond Electromagnetic SignalsReview: Key Features: Unique approach offering the potential for more accurate solutions compared to the standard approaches, especially in the treatment of fast risetime (picosecond) devices and transmitters, that may eventually supplant present standard electromagnetic methods, which have limited validity for very fast phenomenaEmploys the TLM method, that is very intuitive and physically appealing; thus providing a convenient means for incorporating correlation/decorrelation effects, which are relatable to quantum mechanical parametersLists the Program Statements giving the reader a "hands-on" approach to the simulations, which will encourage readers to observe the effects of their own changes in the program
Download or read book The Transmission Line Modeling TLM Method in Electromagnetics written by Christos Christopoulos and published by Springer Nature. This book was released on 2022-06-01 with total page 123 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the topic in electromagnetics known as Transmission-Line Modeling or Matrix method-TLM. While it is written for engineering students at graduate and advanced undergraduate levels, it is also highly suitable for specialists in computational electromagnetics working in industry, who wish to become familiar with the topic. The main method of implementation of TLM is via the time-domain differential equations, however, this can also be via the frequency-domain differential equations. The emphasis in this book is on the time-domain TLM. Physical concepts are emphasized here before embarking onto mathematical development in order to provide simple, straightforward suggestions for the development of models that can then be readily programmed for further computations. Sections with strong mathematical flavors have been included where there are clear methodological advantages forming the basis for developing practical modeling tools. The book can be read at different depths depending on the background of the reader, and can be consulted as and when the need arises.
Download or read book Transmission Line Matrix TLM Techniques for Diffusion Applications written by Donard deCogan and published by Routledge. This book was released on 2018-12-12 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transmission Line Matrix (TLM) is a numerical technique which is based upon establishing an analogue between a space and time dependent physical problem and an electrical network which includes transmission lines. By their very nature these enforce time discretization on the network which can then be solved explicitly in the time-domain. Although it is best known in electromagnetic applications, TLM can also be used to model diffusion phenomena, and this book outlines the state of the art in this area. The first part of the book deals with theory and techniques. The second part is devoted to the development of algorithms for specific applications. This is arranged as a historical sequence starting with heat-flow and matter diffusion. The remainder of the book outlines many of the ingenious exploitations of the unique properties of TLM, including topics such as the solution of convection, Poisson, Laplace, and time-dependent Schrodinger equations. Applications in the firing of ceramics, chromatography, image processing, and the solution of inverse thermal problems are also covered.
Download or read book Numerical Techniques in Electromagnetics Second Edition written by Matthew N.O. Sadiku and published by CRC Press. This book was released on 2000-07-12 with total page 764 pages. Available in PDF, EPUB and Kindle. Book excerpt: As the availability of powerful computer resources has grown over the last three decades, the art of computation of electromagnetic (EM) problems has also grown - exponentially. Despite this dramatic growth, however, the EM community lacked a comprehensive text on the computational techniques used to solve EM problems. The first edition of Numerical Techniques in Electromagnetics filled that gap and became the reference of choice for thousands of engineers, researchers, and students. The Second Edition of this bestselling text reflects the continuing increase in awareness and use of numerical techniques and incorporates advances and refinements made in recent years. Most notable among these are the improvements made to the standard algorithm for the finite difference time domain (FDTD) method and treatment of absorbing boundary conditions in FDTD, finite element, and transmission-line-matrix methods. The author also added a chapter on the method of lines. Numerical Techniques in Electromagnetics continues to teach readers how to pose, numerically analyze, and solve EM problems, give them the ability to expand their problem-solving skills using a variety of methods, and prepare them for research in electromagnetism. Now the Second Edition goes even further toward providing a comprehensive resource that addresses all of the most useful computation methods for EM problems.
Download or read book Numerical Analysis in Electromagnetics written by Pierre Saguet and published by John Wiley & Sons. This book was released on 2013-03-01 with total page 153 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of this book is to give a broad overview of the TLM (Transmission Line Matrix) method, which is one of the “time-domain numerical methods”. These methods are reputed for their significant reliance on computer resources. However, they have the advantage of being highly general. The TLM method has acquired a reputation for being a powerful and effective tool by numerous teams and still benefits today from significant theoretical developments. In particular, in recent years, its ability to simulate various situations with excellent precision, including complex materials, has been demonstrated. Application examples are included in the last two chapters of the book, enabling the reader to draw conclusions regarding the performance of the implemented techniques and, at the same time, to validate them. Contents 1. Basis of the TLM Method: the 2D TLM Method. 2. 3D Nodes. 3. Introduction of Discrete Elements and Thin Wires in the TLM Method. 4. The TLM Method in Matrix Form and the Z Transform. Appendix A. Development of Maxwell’s Equations using the Z Transform with a Variable Mesh. Appendix B. Treatment of Plasma using the Z Transform for the TLM Method.
Download or read book Transmission Line Matrix TLM in Computational Mechanics written by Donard de Cogan and published by CRC Press. This book was released on 2005-11-01 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: The finite element method reigns as the dominant technique for modeling mechanical systems. Originally developed to model electromagnetic systems, the Transmission Line Matrix (TLM) method proves to match, and in some cases exceed, the effectiveness of finite elements for modeling several types of physical systems. Transmission Line Matrix in Computational Mechanics provides a tutorial approach to applying TLM for modeling mechanical and other physical systems. Transmission Line Matrix in Computational Mechanics begins with the history of TLM, an introduction to the theory using mechanical engineering concepts, and the electromagnetic basics of TLM. The authors then demonstrate the theory for use in acoustic propagation, along with examples of MATLAB® code. The remainder of the book explores the application of TLM to problems in mechanics, specifically heat and mass transfer, elastic solids, simple deformation models, hydraulic systems, and computational fluid dynamics. A discussion of state-of-the-art techniques concludes the book, offering a look at the current research undertaken by the authors and other leading experts to overcome the limitations of TLM in applying the method to diverse types of systems. This valuable reference introduces students, engineers, and researchers to a powerful, accurate, and stable alternative to finite elements, providing case studies and examples to reinforce the concepts and illustrate the applications.
Download or read book Modeling and Simulation of Electromagnetic Problems Via the Transmission Line Matrix Method written by M. Orhan Özyalçın and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Today's electromagnetic (EM) problems are very complex. Analytical solutions are available only for some canonical structures and this has lead to an increased interest in numerical electromagnetics. Today, parallel to the increase in computer's capacity and speed, numerical approaches have become rather popular . Improvements in computers have also made it possible to solve EM problems directly in time domain (TD), starting either or from field and network theories. That is why , the transmission line matrix (TLM) and finite difference time domain (FDTD) methods, have enjoyed widespread use in the last decade. TLM is a fast developing technique which was first introduced by P .B. Johns in 1971. At the beginning, three dimensional (3D) problems were simplified and reduced to a generalized 2D nodes (Expanded Node) in the TLM method. Towards the end of the 70's, 3D TLM began to be applied successfully to a wide variety of EM problems. This thesis can be considered as an attempt for increasing the realm of complex EM problems which can be satisfactorily addressed by the TLM method. We will consider two such problems concerning Electromagnetic Compatibility (EMC) and Specific Absorption Rate (SAR) calculations under realistic conditions for which hitherto it has not been possible to generate TLM solutions. Our numerical calculations will show clearly that TLM can satisfactorily be applied to these problem areas. We will also validate our solutions, albeit in a necessarily incomplete manner , by comparing our results with independently generated FDTD solutions of the same problems. It has also to be mentioned that both the TLM and the FDTD algorithms used for this purpose in our work were developed and coded by the author . TLM is based on network theory and involves TD lumped transmission line modeling of the Maxwell's equations in discretized spatial domain. This is an entirely different approach from that used in the FDTD, which relies on the direct discretization of the governing differential equations. TLM involves replacing a continuous system by a network or array of lumped elements. Interrelations and analogies between network equations and Maxwell ' s equations form the basis of this method, and as such it can be considered as being more physical than strictly mathematical discretization approach. Lumped parameters of the transmission line, such as, inductance and capacitance correspond to the electrical parameters relating to the permeability and permittivity distributions in the corresponding EM problem, respectively .Currents and voltages on the other hand, correspond to the magnetic and electrical field components in the system. There are many different TLM versions in the literature. Here, the most powerful of these approaches, namely the 3' symmetrical condensed node (SCN) TLM version is used. The main advantage of this node structure over the others and over the FDTD method is the symmetry it provides and the fact that the calculation of all the 6 field components is accomplished at the same time step. Each SCN- TLM node is represented by a scattering matrix, S, with which the reflected voltage pulses are related to the incident voltage pulses during the simulation time. On the other hand, there are two main drawbacks of the TLM method, which are the requirement of (İ) large computer memories, and (İİ) high simulation times. The organization of this work is as follows: .Chapter 2 is devoted to a fairly complete and detailed treatment of TLM method in 2D and 3D. In this chapter we critically investigate the various TLM algorithms based on different node structures and assess relative merits in relation to their respective computational requirements and the accuracies (numerical dispersion effects) they provide. .In Chapter 3, two canonical problems, (i) the Green's function representation in a PEC resonator and, (ii) radiation from an aperture, are considered for the purposes of validation (calibration) of our codes. The calibration is done via comparisons both in TD and frequency domain (FD). Analytical representations of these two canonical problems are derived in the FD, therefore comparisons in this domain are straightforward. The TLM results are transformed to the FD via discrete Fourier transformation (DFT). On the other hand, broad band TD comparisons are difficult and one needs to follow the steps given below: o The TLM results are obtained directly by using a broad band pulse as a source and the response is obtained directly in the TD. o FD results are calculated separately at chosen sampling frequencies of the broad band pulse used in TLM simulation via analytical representations. Frequency domain results are weighed with the source spectrum and inverse DFT is applied to obtain the TD analytical results. During this process, one must take the frequency resolution criteria into the consideration to get correct results. .In Chapter 4, after having successfully calibrated our TLM code ( and also FDTD which is used to obtain comparison solutions) we proceed to investigate the complex problems which constitute the main original contribution of this work. These are the Shielding Effectiveness (SE) and the Specific Absorption Rate (SAR) simulations for which, where no TLM solutions are available. SE is an effective parameter in EM compatibility (EMC) problems and is used as a criterion for assessing a structure's susceptibility to EM interference. As a realistic prototype of EMC problems in this thesis we have considered a resonator with an aperture for SE modeling. The second problem we investigated concerns SAR calculations. SAR is the only parameter in bio-EM where device-human tissue interaction is of interest. The determination of SAR is an extremely complex problem and can be addressed either via difficult to perform laboratory measurements or via numerical methods using simulated tissue prototypes. In this thesis we have considered the nowadays rather actual problem of calculating SAR distributions in human head models. Extensive calculations for different parameter regimes are done for both problems and the TLM results are compared against the FDTD results and, in the SE case, also with the results given in the literature as obtained via Method of Moments (MoM) and validated experimentally .In all cases our results were in rather good agreement with the comparison solutions used. .Finally , in Chapter 5 we present some concluding remarks together with suggestions for future work.
Download or read book The Electromagnetic Wave Simulator written by Wolfgang J. R. Hoefer and published by Wiley. This book was released on 1991-08-15 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excellent coverage of the two-dimensional transmission line matrix (TLM) method of electromagnetic field modeling and TLM electromagnetic wave simulation software for MS-DOS computers is detailed. Divided into 3 sections, it begins with a comprehensive treatment of the two-dimensional TLM method, including all concepts and procedures incoporated in the field-modeling part of the software. An expansive user's manual and tutorial, which describes various features of the simulator using numerous examples, comprises the middle section. Concludes with a unique selection of experiments for a typical course in microwaves and electromagnetics.
Download or read book Electromagnetic Fields written by Jean G. Van Bladel and published by John Wiley & Sons. This book was released on 2007-05-23 with total page 1171 pages. Available in PDF, EPUB and Kindle. Book excerpt: Professor Jean Van Bladel, an eminent researcher and educator in fundamental electromagnetic theory and its application in electrical engineering, has updated and expanded his definitive text and reference on electromagnetic fields to twice its original content. This new edition incorporates the latest methods, theory, formulations, and applications that relate to today's technologies. With an emphasis on basic principles and a focus on electromagnetic formulation and analysis, Electromagnetic Fields, Second Edition includes detailed discussions of electrostatic fields, potential theory, propagation in waveguides and unbounded space, scattering by obstacles, penetration through apertures, and field behavior at high and low frequencies.
Download or read book Numerical Techniques in Electromagnetics with MATLAB written by Matthew N.O. Sadiku and published by CRC Press. This book was released on 2018-10-08 with total page 469 pages. Available in PDF, EPUB and Kindle. Book excerpt: Despite the dramatic growth in the availability of powerful computer resources, the EM community lacks a comprehensive text on the computational techniques used to solve EM problems. The first edition of Numerical Techniques in Electromagnetics filled that gap and became the reference of choice for thousands of engineers, researchers, and students. This third edition of the bestselling text reflects the continuing increase in awareness and use of numerical techniques and incorporates advances and refinements made in recent years. Most notable among these are the improvements made to the standard algorithm for the finite-difference time-domain (FDTD) method and treatment of absorbing boundary conditions in FDTD, finite element, and transmission-line-matrix methods. The author also has added a chapter on the method of lines. Numerical Techniques in Electromagnetics with MATLAB®, Third Edition continues to teach readers how to pose, numerically analyze, and solve EM problems, to give them the ability to expand their problem-solving skills using a variety of methods, and to prepare them for research in electromagnetism. Now the Third Edition goes even further toward providing a comprehensive resource that addresses all of the most useful computation methods for EM problems and includes MATLAB code instead of FORTRAN.
Download or read book Time Domain Methods in Electrodynamics written by Peter Russer and published by Springer Science & Business Media. This book was released on 2008-09-26 with total page 423 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book consists of contributions given in honor of Wolfgang J.R. Hoefer. Space and time discretizing time domain methods for electromagnetic full-wave simulation have emerged as key numerical methods in computational electromagnetics. Time domain methods are versatile and can be applied to the solution of a wide range of electromagnetic field problems. Computing the response of an electromagnetic structure to an impulsive excitation localized in space and time provides a comprehensive characterization of the electromagnetic properties of the structure in a wide frequency range. The most important methods are the Finite Difference Time Domain (FDTD) and the Transmission Line Matrix (TLM) methods. The contributions represent the state of the art in dealing with time domain methods in modern engineering electrodynamics for electromagnetic modeling in general, the Transmission Line Matrix (TLM) method, the application of network concepts to electromagnetic field modeling, circuit and system applications and, finally, with broadband devices, systems and measurement techniques.
Download or read book Computational Electromagnetics with MATLAB Fourth Edition written by Matthew N.O. Sadiku and published by CRC Press. This book was released on 2018-07-20 with total page 687 pages. Available in PDF, EPUB and Kindle. Book excerpt: This fourth edition of the text reflects the continuing increase in awareness and use of computational electromagnetics and incorporates advances and refinements made in recent years. Most notable among these are the improvements made to the standard algorithm for the finite-difference time-domain (FDTD) method and treatment of absorbing boundary conditions in FDTD, finite element, and transmission-line-matrix methods. It teaches the readers how to pose, numerically analyze, and solve EM problems, to give them the ability to expand their problem-solving skills using a variety of methods, and to prepare them for research in electromagnetism. Includes new homework problems in each chapter. Each chapter is updated with the current trends in CEM. Adds a new appendix on CEM codes, which covers commercial and free codes. Provides updated MATLAB code.