Principles and Techniques of Electromagnetic Compatibility 2nd Edition By Christos Christopoulos

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Principles and Techniques of Electromagnetic Compatibility 2nd Edition By Christos Christopoulos

Contents

Preface to the Second Edition…………………………………………. xiii
Preface ……………………………………………………………………………..xv
The Author ……………………………………………………………………. xvii
Part I Underlying Concepts and Techniques
1 Introduction to Electromagnetic Compatibility ……………………1
2 Electromagnetic Fields………………………………………………………..5
2.1 Static Fields ………………………………………………………………………………..6
2.1.1 Electric Field ……………………………………………………………………6
2.1.2 Magnetic Field ………………………………………………………………..15
2.2 Quasistatic Fields……………………………………………………………………….22
2.2.1 The Relationship between Circuits and Fields……………………26
2.2.2 Electromagnetic Potentials……………………………………………….31
2.3 High-Frequency Fields………………………………………………………………..33
2.3.1 Electromagnetic Waves…………………………………………………….34
2.3.2 Radiating Systems……………………………………………………………39
References ………………………………………………………………………………………..53
3 Electrical Circuit Components …………………………………………..55
3.1 Lumped Circuit Components ……………………………………………………..55
3.1.1 Ideal Lumped Components………………………………………………56
3.1.2 Real Lumped Components……………………………………………….57
3.2 Distributed Circuit Components …………………………………………………64
3.2.1 Time-Domain Analysis of Transmission Lines………………………67
3.2.2 Frequency-Domain Analysis of Transmission Lines………………70
References ………………………………………………………………………………………..76
4 Electrical Signals and Circuits……………………………………………77
4.1 Representation of a Signal in Terms of Simpler Signals ………………….78
4.2 Correlation Properties of Signals …………………………………………………88
4.2.1 General Correlation Properties …………………………………………89
4.2.2 Random Signals ………………………………………………………………90
4.3 The Response of Linear Circuits to Deterministic and Random
Signals………………………………………………………………………………………92
4.3.1 Impulse Response …………………………………………………………..92
4.3.2 Frequency Response ……………………………………………………….93
4.3.3 Detection of Signals in Noise …………………………………………..95
4.4 The Response of Nonlinear Circuits ……………………………………………98
4.5 Characterization of Noise …………………………………………………………100
References ………………………………………………………………………………………108
Part II General EMC Concepts and Techniques
5 Sources of Electromagnetic Interference………………………….111
5.1 Classification of Electromagnetic Interference Sources ………………..111
5.2 Natural Electromagnetic Interference Sources…………………………….112
5.2.1 Low-Frequency Electric and Magnetic Fields ……………………112
5.2.2 Lightning ……………………………………………………………………..113
5.2.3 High-Frequency Electromagnetic Fields …………………………..117
5.3 Man-Made Electromagnetic Interference Sources ………………………..118
5.3.1 Radio Transmitters…………………………………………………………118
5.3.2 Electroheat Applications ………………………………………………..119
5.3.3 Digital Signal Processing and Transmission ………………………119
5.3.4 Power Conditioning and Transmission …………………………….122
5.3.4.1 Low-Frequency Conducted Interference ……………..122
5.3.4.2 Low-Frequency Radiated Interference …………………123
5.3.4.3 High-Frequency Conducted Interference …………….124
5.3.4.4 High-Frequency Radiated Interference ………………..124
5.3.5 Switching Transients………………………………………………………125
5.3.5.1 Nature and Origin of Transients………………………….125
5.3.5.2 Circuit Behavior during Switching Assuming an
Idealized Switch ……………………………………………….126
5.3.5.3 Circuit Behavior during Switching Assuming a
Realistic Model of the Switch …………………………….131
5.3.6 The Electrostatic Discharge (ESD)…………………………………..135
5.3.7 The Nuclear Electromagnetic Pulse (NEMP) and High
Power Electromagnetics (HPEM)…………………………………….137
5.4 Surveys of the Electromagnetic Environment……………………………..139
References ………………………………………………………………………………………139
6 Penetration through Shields and Apertures……………………..143
6.1 Introduction ……………………………………………………………………………143
6.2 Shielding Theory ……………………………………………………………………..145
6.2.1 Shielding Effectiveness…………………………………………………..145
6.2.2 Approximate Methods — The Circuit Approach……………….146
6.2.3 Approximate Methods — The Wave Approach …………………156
6.2.4 Analytical Solutions to Shielding Problems ………………………161
6.2.5 General Remarks Regarding Shielding Effectiveness at
Different Frequencies…………………………………………………….161
6.2.6 Surface Transfer Impedance and Cable Shields …………………163
6.3 Aperture Theory………………………………………………………………………167
6.4 Rigorous Calculation of the Shielding Effectiveness (SE) of a
Conducting Box with an Aperture …………………………………………….174
6.5 Intermediate Level Tools for SE Calculations ………………………………176
6.6 Numerical Simulation Methods for Penetration through Shields
and Apertures ………………………………………………………………………….185
6.6.1 Classification of Numerical Methods ……………………………….185
6.6.2 The Application of Frequency-Domain Methods……………….187
6.6.3 The Application of Time-Domain Methods……………………….190
6.7 Treatment of Multiple Apertures through a Digital Filter Interface… 194
6.8 Further Work Relevant to Shielding……………………………………………200
References ………………………………………………………………………………………201
7 Propagation and Crosstalk ………………………………………………207
7.1 Introduction ……………………………………………………………………………207
7.2 Basic Principles ……………………………………………………………………….210
7.3 Line Parameter Calculation ……………………………………………………….223
7.3.1 Analytical Methods………………………………………………………..223
7.3.2 Numerical Methods……………………………………………………….231
7.4 Representation of EM Coupling from External Fields ………………….232
7.5 Determination of the EM Field Generated by Transmission Lines…. 246
7.6 Numerical Simulation Methods for Propagation Studies ………………252
References ………………………………………………………………………………………253
8 Simulation of the Electromagnetic Coupling between
Systems…………………………………………………………………………..257
8.1 Overview………………………………………………………………………………..257
8.2 Source/External Environment……………………………………………………258
8.3 Penetration and Coupling …………………………………………………………259
8.4 Propagation and Crosstalk ………………………………………………………..270
8.5 Device Susceptibility and Emission ……………………………………………273
8.6 Numerical Simulation Methods………………………………………………….274
8.6.1 The Finite-Difference Time-Domain (FD-TD) Method ………..275
8.6.2 The Transmission-Line Modeling (TLM) Method ……………….275
8.6.3 The Method of Moments (MM) ………………………………………276
8.6.4 The Finite-Element (FE) Method……………………………………..276
References ………………………………………………………………………………………278
9 Effects of Electromagnetic Interference on Devices and
Systems…………………………………………………………………………..281
9.1 Immunity of Analogue Circuits ………………………………………………….283
9.2 The Immunity of Digital Circuits……………………………………………….284
References ………………………………………………………………………………………288
Part III Interference Control Techniques
10 Shielding and Grounding ………………………………………………..291
10.1 Equipment Screening……………………………………………………………….291
10.1.1 Practical Levels of Attenuation………………………………………..292
10.1.2 Screening Materials ……………………………………………………….292
10.1.3 Conducting Penetrations………………………………………………..297
10.1.4 Slits, Seams, and Gasketing……………………………………………..297
10.1.5 Damping of Resonances ………………………………………………..299
10.1.6 Measurement of Screening Effectiveness …………………………299
10.2 Cable Screening ………………………………………………………………………300
10.2.1 Cable Transfer Impedance………………………………………………300
10.2.2 Earthing of Cable Screens………………………………………………301
10.2.3 Cable Connectors………………………………………………………….302
10.3 Grounding ………………………………………………………………………………303
10.3.1 Grounding in Large-Scale Systems …………………………………..304
10.3.2 Grounding in Self-Contained Equipment………………………….307
10.3.3 Grounding in an Environment of Interconnected
Equipment……………………………………………………………………308
References ………………………………………………………………………………………309
11 Filtering and Nonlinear Protective Devices………………………311
11.1 Power-Line Filters…………………………………………………………………….311
11.2 Isolation………………………………………………………………………………….316
11.3 Balancing ………………………………………………………………………………..319
11.4 Signal-Line Filters …………………………………………………………………….320
11.5 Nonlinear Protective Devices ……………………………………………………320
References ………………………………………………………………………………………326
12 General EMC Design Principles ……………………………………….329
12.1 Reduction of Emissions at Source ……………………………………………..330
12.2 Reduction of Coupling Paths…………………………………………………….331
12.2.1 Operating Frequency and Rise-Time ……………………………….331
12.2.2 Reflections and Matching……………………………………………….333
12.2.3 Ground Paths and Ground Planes …………………………………..334
12.2.4 Circuit Segregation and Placement………………………………….335
12.2.5 Cable Routing……………………………………………………………….336
12.3 Improvements in Immunity ………………………………………………………336
12.3.1 Immunity by Software Design ………………………………………..338
12.3.2 Spread Spectrum Techniques………………………………………….339
12.4 The Management of EMC …………………………………………………………342
References ………………………………………………………………………………………344
Part IV EMC Standards and Testing
13 EMC Standards………………………………………………………………..347
13.1 The Need for Standards ……………………………………………………………347
13.2 The International Framework ……………………………………………………348
13.3 Civilian EMC Standards …………………………………………………………….349
13.3.1 FCC Standards ………………………………………………………………349
13.3.2 European Standards……………………………………………………….351
13.3.3 Other EMC Standards…………………………………………………….354
13.3.4 Sample Calculation for Conducted Emission ……………………354
13.4 Military Standards…………………………………………………………………….357
13.4.1 Military Standard MIL-STD-461D……………………………………..357
13.4.2 Defence Standard DEF-STAN 59-41………………………………….359
13.5 Company Standards………………………………………………………………….360
13.6 EMC at Frequencies above 1 GHz ……………………………………………..360
13.7 Human Exposure Limits to EM Fields ………………………………………..364
References ………………………………………………………………………………………368
14 EMC Measurements and Testing ………………………………………371
14.1 EMC Measurement Techniques ………………………………………………….371
14.2 Measurement Tools…………………………………………………………………..372
14.2.1 Sources ………………………………………………………………………..372
14.2.2 Receivers ……………………………………………………………………..373
14.2.3 Field Sensors ………………………………………………………………..375
14.2.4 Antennas………………………………………………………………………376
14.2.5 Assorted Instrumentation……………………………………………….380
14.3 Test Environments……………………………………………………………………383
14.3.1 Open-Area Test Sites………………………………………………………384
14.3.2 Screened Rooms……………………………………………………………387
14.3.3 Reverberating Chambers………………………………………………..391
14.3.4 Special EMC Test Cells …………………………………………………..396
References ………………………………………………………………………………………397
Part V EMC in Systems Design
15 EMC and Signal Integrity (SI)…………………………………………..403
15.1 Introduction ……………………………………………………………………………403
15.2 Transmission Lines as Interconnects ………………………………………….408
15.3 Board and Chip Level EMC……………………………………………………….422
15.3.1 Simultaneous Switching Noise (SSN)……………………………….422
15.3.2 Physical Models…………………………………………………………….426
15.3.3 Behavioral Models …………………………………………………………433
References ………………………………………………………………………………………435
16 EMC and Wireless Technologies ………………………………………437
16.1 The Efficient Use of the Frequency Spectrum…………………………….439
16.2 EMC, Interoperability, and Coexistence ………………………………………442
16.3 Specifications and Alliances ………………………………………………………449
16.4 Conclusions …………………………………………………………………………….455
References ………………………………………………………………………………………456
17 EMC and Broadband Technologies…………………………………..459
17.1 Transmission of High-Frequency Signals over Telephone and
Power Networks ……………………………………………………………………..460
17.2 EMC and Digital Subscriber Lines (xDSL) …………………………………..463
17.3 EMC and Power Line Telecommunications (PLT) ………………………..465
17.4 Regulatory Framework for Emissions from xDSL/PLT and Related
Technologies …………………………………………………………………………..466
References ………………………………………………………………………………………467
18 EMC and Safety……………………………………………………………….471
References ………………………………………………………………………………………473
19 Statistical EMC…………………………………………………………………475
19.1 Introduction ……………………………………………………………………………475
19.2 The Basic Stochastic Problem……………………………………………………477
19.3 A Selection of Statistical Approaches to Complex EMC Problems … 481
References ………………………………………………………………………………………484
Appendices
A Useful Vector Formulae …………………………………………………..485
B Circuit Parameters of Some Conductor Configurations…….489
C The sinx/x Function ……………………………………………………….495
D Spectra of Trapezoidal Waveforms…………………………………..499
E Calculation of the Electric Field Received by a Short
Electric Dipole ………………………………………………………………..503

Preface to the Second Edition

In preparing the second edition of this book I have adhered to the same
principles as in the first edition, namely, to present the topic of EMC to
a wide range of readers and enable as many of them as possible to benefit
from the experience and the work of others. A practical approach is
adopted whenever appropriate but mathematical analysis and numerical
techniques are also presented in connection with the development of EMC
predictive tools. I have tried to present the physical basis and analytical
models of important interactions in EMC and whenever the mathematical
framework became too complex I have guided the interested reader to
relevant references. Readers therefore will be able to study the material
at a depth appropriate to their skills and interests.
The main thrust of the new edition was to update material, extend the
treatment of some topics that are not covered adequately in the first
edition, introduce new topics that ten years ago had not emerged as
important in EMC, and add more worked examples. Part V is entirely new
and covers new and emerging technologies that are having a major impact
in EMC theory and practice.
Again, I gratefully acknowledge the support and friendship over the
years of professional colleagues at Nottingham and elsewhere.

Preface

Electromagnetic compatibility (EMC) may be approached from two standpoints.
In the first approach, one is tempted to address the problem in
its generality and seek the development of general tools to predict performance.
The complexity of the problem is such that it is not at present
possible to make decisive progress along this route and one is left with
a collection of mathematical treatises of limited immediate applicability.
It is also generally the case that a physical grasp of the problem cannot
be easily attained in this way, since mathematical complexity dominates all.
An alternative approach is to view EMC from the multiplicity of practical
problems that confront designers on a day-to-day basis. The general
appearance of such work is a collection of “EMC recipes and fixes” based
on a mixture of theoretical ideas, practical experience, and black magic,
which no doubt work under certain circumstances. The student of such
works is left, however, without a clear physical grasp of exactly what is
happening or an understanding of the range of validity of the formulae
he or she is supplied with.
The current text adopts a different viewpoint. Emphasis is placed on
understanding the relevant electromagnetic interactions in increasingly
complex systems. Mathematical tools are introduced as and when pursuing
the physical picture unaided becomes counterproductive.
Approximations and intuitive ideas are also included and an effort is
made to define the limitations of each approach. As the reader becomes
aware of the physics of EMC interactions and has some mathematical tools
at his or her disposal, then the manner in which systems can be engineered
to achieve EMC is described and illustrated with practical examples. Many
readers will find that the confidence felt when they become familiar with
the physical, mathematical, and engineering aspects of EMC is not sufficient
to predict the performance of complex systems. In order to handle
complexity, numerical tools are developed and the basis and capabilities
of these tools are presented. It is hoped that the text will provide useful
source material for a serious study of EMC, including references to more
advanced work.
The text aims to be comprehensive, although, in a topic of such a
wide coverage as EMC, it is difficult to make a selection of material to
be included that will appeal to all readers. The text will be useful to all
those engaged in EMC analysis and design either as advanced undergraduates,
postgraduates, or EMC engineers in industry. The author is, by
training and temperament, inclined to take a global view of problems and
he hopes that readers will choose to study the entire book at a pace that
reflects their own background and interests. However, as guidance for
those who may require a selection of topics for a first reading, the
following two schemes are suggested:
i. EMC applications-oriented readers — Chapter 1, Sections 2.1, 3.1,
4.1, 4.4; Chapter 5; and all material in Parts III and IV.
ii. EMC analysis-oriented readers — All material in Parts I and II and
Chapter 13.
Part I contains material underlying all work in electrical and electronic
engineering and it is thus also relevant to EMC. Readers with a degree in
electrical engineering will be familiar with a large part of this material.
Part II deals with general EMC concepts and techniques and it is thus
useful to those engaged in predicting the EMC behavior of systems. More
practical techniques used to control electromagnetic interference and the
design of EMC into products are presented in Part III. Finally, the main
EMC standards and test techniques are described in Part IV.
It is a pleasure to acknowledge the help and support I have received
over the years from co-workers at Nottingham University and other higher
educational establishments and from those in industry and government
laboratories who, by sponsoring work in EMC, have contributed to my
understanding of the subject. Miss S. E. Hollingsworth expertly typed large
parts of the manuscript and I am grateful to her for doing this with the
minimum of fuss.