Electromagnetic Shielding: Theory and Applications

Description

Comprehensive Resource for Understanding Electromagnetic Shielding Concepts and Recent Developments in the Field This book describes the fundamental, theoretical, and practical aspects to approach electromagnetic shielding with a problem-solving mind, either at a design stage or in the context of an issue-fixing analysis of an existing configuration. It examines the main shielding mechanisms and how to analyze any shielding configuration, taking into account all the involved aspects. A detailed discussion on the possible choices of parameters suitable to ascertain the performance of a given shielding structure is also presented by considering either a continuous wave EM field source or a transient one. To aid in reader comprehension, both a theoretical and a practical engineering point of view are presented with several examples and applications included at the end of main chapters. Sample topics discussed in the book include: Concepts in transient shielding including performance parameters and canonical configurationsTime domain performance of shielding structures, thin shields, and overall performance of shielding enclosures (cavities)How to install adequate barriers around the most sensitive components/systems to reduce or eliminate interferenceDetails on solving core fundamental issues for electronic and telecommunications systems via electromagnetic shielding For industrial researchers, telecommunications/electrical engineers, and academics studying the design of EM shielding structures, this book serves as an important resource for understanding both the logistics and practical applications of electromagnetic shielding. It also includes all recent developments in the field to help professionals stay ahead of the curve in their respective disciplines. Cover Title Page Copyright Contents About the Authors Preface Chapter 1 Electromagnetics Behind Shielding 1.1 Definitions 1.2 Notation, Symbology, and Acronyms 1.3 Macroscopic Electromagnetism and Maxwell's Equations 1.4 Constitutive Relations 1.5 Discontinuities and Singularities 1.6 Initial Conditions, Boundary Conditions, and Causality 1.7 Poynting's Theorem and Energy Considerations 1.8 Fundamental Theorems 1.8.1 Uniqueness Theorem 1.8.2 Reciprocity Theorem 1.8.3 Equivalence Principle 1.8.4 Duality 1.8.5 Symmetry 1.8.6 Image Principle 1.8.7 Babinet's Principle 1.9 Wave Equations, Helmholtz's Equations, Potentials, and Green's Functions 1.10 Basic Shielding Mechanisms 1.11 Source Inside or Outside the Shielding Structure and Reciprocity References Chapter 2 Shielding Materials 2.1 Standard Metallic and Ferromagnetic Materials 2.2 Ferrimagnetic Materials 2.3 Ferroelectric Materials 2.4 Thin Films and Conductive Coatings 2.5 Other Materials Suitable for EM Shielding Applications 2.5.1 Structural Materials 2.5.2 Conductive Polymers 2.5.3 Conductive Glasses and Transparent Materials 2.5.4 Conductive (and Ferromagnetic or Ferrimagnetic) Papers 2.6 Special Materials 2.6.1 Metamaterials and Chiral Materials 2.6.2 Composite Materials 2.6.3 Graphene 2.6.4 Other Nanomaterials 2.6.5 High‐Temperature Superconductors References Chapter 3 Figures of Merit for Shielding Configurations 3.1 (Local) Shielding Effectiveness 3.2 The Global Point of View 3.3 Other Proposals of Figures of Merit 3.4 Energy‐Based, Content‐Oriented Definition 3.5 Performance of Shielded Cables References Chapter 4 Shielding Effectiveness: Plane Waves 4.1 Electromagnetic Plane Waves: Definitions and Properties 4.2 Uniform Plane Waves Incident on a Planar Shield 4.2.1 Transmission‐Line Approach 4.2.2 The Single Planar Shield 4.2.3 Multiple (or Laminated) Shields 4.3 Plane Waves Normally Incident on Cylindrical Shielding Surfaces 4.4 Plane Waves Against Spherical Shields 4.5 Extension of the TL Analogy to Near‐Field Sources 4.5.1 Examples References Chapter 5 Shielding Effectiveness: Near‐Field Sources 5.1 Spectral‐Domain Approach 5.1.1 Maxwell's Equations in the Spectral Domain 5.1.2 TM/TE Decomposition and Equivalent Transmission Lines 5.1.3 Spectral Dyadic Green's Functions 5.1.4 Field Evaluation in the Spatial Domain 5.2 LF Magnetic Shielding of Metal Plates: Parallel Loop 5.2.1 Spectral‐Domain Approach 5.2.2 Vector Magnetic‐Potential Approach 5.2.3 Approximate Formulations 5.3 LF Magnetic Shielding of Metal Plates: Perpendicular Loop 5.4 LF Magnetic Shielding of Metal Plates: Parallel Current Line References Chapter 6 Transient Shielding 6.1 Performance Parameters: Definitions and Properties 6.2 Transient Sources: Plane Waves and Dipoles 6.2.1 Transient Uniform Plane Waves 6.2.2 Transient Dipoles 6.3 Numerical Solutions via Inverse‐Fourier Transform 6.4 Analytical Solutions in Canonical Configurations 6.4.1 Transient Plane Waves on a Single‐Layer Screen 6.4.2 Transient Dipoles: The Cagniard–de Hoop Method 6.4.2.1 Thin Conductive Sheet 6.4.2.2 Graphene Sheet 6.4.2.3 Generalizations: Thick Shields, Multilayered Shields References Chapter 7 Numerical Methods for Shielding Analyses 7.1 Finite‐Element Method 7.2 Method of Moments 7.3 Finite‐Difference Time‐Domain Method 7.4 Finite Integration Technique 7.5 Transmission‐Line Matrix Method 7.6 Partial Element Equivalent Circuit Method 7.7 Test Case for Comparing Numerical Methods References Chapter 8 Apertures in Planar Metal Screens 8.1 Historical Background 8.2 Statement of the Problem 8.3 Low‐Frequency Analysis: Transmission Through Small Apertures 8.4 The Small Circular Aperture 8.4.1 Bethe's Theory 8.4.2 Spectral‐Domain Formulation 8.5 Small Noncircular Apertures 8.6 Finite Number of Small Apertures 8.7 Apertures of Arbitrary Shape: Integral‐Equation Formulation 8.8 Rules of Thumb References Chapter 9 Enclosures 9.1 Modal Expansion of Electromagnetic Fields Inside a Metallic Enclosure 9.2 Oscillations Inside an Ideal Source‐Free Enclosure 9.3 The Enclosure Dyadic Green Function 9.4 Excitation of a Metallic Enclosure 9.5 Damped Oscillations Inside Enclosures with Lossy Walls and Quality Factor 9.6 Apertures in Perfectly Conducting Enclosures 9.6.1 Small‐Aperture Approximation 9.6.2 Rigorous Analysis: Integral‐Equation Formulation 9.6.3 Aperture‐Cavity Resonances 9.7 Small Loading Effects 9.8 The Rectangular Enclosure 9.8.1 Symmetry Considerations 9.9 Shielding Effectiveness of a Rectangular Enclosure with an Aperture 9.9.1 Numerical Models 9.9.2 Analytical Models 9.10 Case Study: Rectangular Enclosure with a Circular Aperture 9.10.1 External Sources: Plane‐Wave Excitation 9.10.2 Internal Sources: Electric and Magnetic Dipole Excitations 9.11 Overall Performance in the Frequency Domain 9.12 Overall Performance in the Time Domain References Chapter 10 Cable Shielding 10.1 Transfer Impedance in Tubular Shielded Cables and Aperture Effects 10.2 Relationship Between Transfer Impedance and Shielding Effectiveness 10.3 Actual Cables and Harnesses References Chapter 11 Components and Installation Guidelines 11.1 Gaskets 11.2 Shielded Windows 11.3 Electromagnetic Absorbers 11.4 Shielded Connectors 11.5 Air‐Ventilation Systems 11.6 Fuses, Switches, and Other Similar Components References Chapter 12 Frequency Selective Surfaces 12.1 Analysis of Periodic Structures 12.1.1 Floquet Theorem and Spatial Harmonics 12.1.2 Plane‐Wave Incidence on a Planar 1D Periodic Structure 12.1.3 Plane‐Wave Incidence on a Planar 2D Periodic Structure 12.1.4 Integral Equation Formulation for Plane‐Wave Incidence and Periodic Green's Function 12.1.5 Dipole Excitation of Planar 2D Periodic Structure 12.2 High‐ and Low‐Pass FSSs 12.3 Band‐Pass and Band‐Stop FSSs 12.3.1 Center‐Connected Elements or N‐Pole Elements 12.3.2 Loop‐Type Elements 12.3.3 Solid‐Interior‐Type Elements 12.3.4 Combinations and Fractal Elements 12.4 Recent Trends in FSSs 12.4.1 Multilayer and Cascaded FSSs 12.4.2 3‐D FSSs 12.4.3 2.5‐D FSSs 12.4.4 Reconfigurable and Active FSSs 12.5 Absorbing FSSs 12.5.1 Circuit Analog Absorbers 12.5.2 Absorptive Frequency Selective Reflection/Transmission Structures 12.5.2.1 AFSR Structures 12.5.2.2 AFST Structures (Frequency‐Selective Rasorbers) 12.6 Modeling and Design of FSSs References Chapter 13 Shielding Design Guidelines 13.1 Establishment of the Shielding Requirements 13.2 Assessment of the Number and Types of Functional Discontinuities 13.3 Assessment of Dimensional Constraints and Non‐Electromagnetic Characteristics of Materials 13.4 Estimation of Shielding Performance References Chapter 14 Uncommon Ways of Shielding 14.1 Active Shielding 14.2 Partial Shields 14.3 Chiral Shielding 14.4 Metamaterial Shielding References Appendix A Electrostatic Shielding A.1 Basic Laws of Electrostatics A.2 Electrostatic Tools: Electrostatic Potential and Green's Functions A.3 Electrostatic Shields A.3.1 Conductive Electrostatic Shields A.3.2 Dielectric Electrostatic Shields A.3.3 Aperture Effects in Conductive Shields References Appendix B Magnetic Shielding B.1 Magnetic Shielding Mechanism B.2 Calculation Methods B.3 Boundary‐Value Problems B.3.1 Spherical Magnetic Conducting Shield B.3.2 Cylindrical Magnetic Conducting Shield in a Transverse Magnetic Field B.3.3 Cylindrical Magnetic Conducting Shield in a Parallel Magnetic Field B.4 Ferromagnetic Shields with Hysteresis References Appendix C Statistical Electromagnetics for Shielding Enclosures C.1 Statistical Analyses C.2 Examples References Appendix D Standards and Measurement Methods for Shielding Applications D.1 MIL‐STD 285 and IEEE STD‐299 D.2 NSA 65‐6 and NSA 94‐106 D.3 ASTM E1851 D.4 ASTM D4935 D.5 MIL‐STD 461G D.6 Code of Federal Regulations, Title 47, Part 15 D.7 ANSI/SCTE 48‐3 D.8 MIL‐STD 1377 D.9 IEC Standards D.10 ITU‐T Recommendations D.11 Automotive Standards References Index EULA