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EMC (electromagnetic compatibility)--Principles and Techniques



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Electromagnetic compatibility (EMC) may be approached from two stand points. 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 learner 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 guide 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 Learner 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 Learners 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 Learners. 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 Learners 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 Learners.

ii. EMC analysis-oriented Learners.

Part I contains material underlying all work in electrical and electronic engineering and it is thus also relevant to EMC. Learners 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.


Part I Underlying Concepts and Techniques

1 Introduction to Electromagnetic Compatibility

2 Electromagnetic Fields

  • 1 Static Fields
    • 1.1 Electric Field
    • 1.2 Magnetic Field
  • 2 Quasistatic Fields
    • 2.1 The Relationship between Circuits and Fields
    • 2.2 Electromagnetic Potentials
  • 3 High-Frequency Fields
    • 3.1 Electromagnetic Waves
    • 3.2 Radiating Systems

3 Electrical Circuit Components

  • 1 Lumped Circuit Components
  • 1.1 Ideal Lumped Components
  • 1.2 Real Lumped Components
  • 2 Distributed Circuit Components
    • 2.1 Time-Domain Analysis of Transmission Lines
    • 2.2 Frequency-Domain Analysis of Transmission Lines

4 Electrical Signals and Circuits

  • 1 Representation of a Signal in Terms of Simpler Signals
  • 2 Correlation Properties of Signals
    • 2.1 General Correlation Properties
    • 2.2 Random Signals
  • 3 The Response of Linear Circuits to Deterministic and Random Signals
    • 3.1 Impulse Response
    • 3.2 Frequency Response
    • 3.3 Detection of Signals in Noise
  • 4 The Response of Nonlinear Circuits
  • 5 Characterization of Noise

Part II General EMC Concepts and Techniques

5 Sources of Electromagnetic Interference

  • 1 Classification of Electromagnetic Interference Sources
  • 2 Natural Electromagnetic Interference Sources
    • 2.1 Low-Frequency Electric and Magnetic Fields
    • 2.2 Lightning
    • 2.3 High-Frequency Electromagnetic Fields
  • 3 Man-Made Electromagnetic Interference Sources
    • 3.1 Radio Transmitters
    • 3.2 Electroheat Applications
    • 3.3 Digital Signal Processing and Transmission
    • 3.4 Power Conditioning and Transmission
      • 3.4.1 Low-Frequency Conducted Interference
      • 3.4.2 Low-Frequency Radiated Interference
      • 3.4.3 High-Frequency Conducted Interference
      • 3.4.4 High-Frequency Radiated Interference
    • 3.5 Switching Transients
    • 3.5.1 Nature and Origin of Transients
      • 3.5.2 Circuit Behavior during Switching Assuming an Idealized Switch
      • 3.5.3 Circuit Behavior during Switching Assuming a Realistic Model of the Switch
    • 3.6 The Electrostatic Discharge (ESD)
    • 3.7 The Nuclear Electromagnetic Pulse (NEMP) and High Power Electromagnetics (HPEM)
  • 4 Surveys of the Electromagnetic Environment

6 Penetration through Shields and Apertures

  • 1 Introduction
  • 2 Shielding Theory
    • 2.1 Shielding Effectiveness
    • 2.2 Approximate Methods - The Circuit Approach
    • 2.3 Approximate Methods - The Wave Approach
    • 2.4 Analytical Solutions to Shielding Problems
    • 2.5 General Remarks Regarding Shielding Effectiveness at Different Frequencies
    • 2.6 Surface Transfer Impedance and Cable Shields
  • 3 Aperture Theory
  • 4 Rigorous Calculation of the Shielding Effectiveness (SE) of a Conducting Box with an Aperture
  • 5 Intermediate Level Tools for SE Calculations
  • 6 Numerical Simulation Methods for Penetration through Shields and Apertures
    • 6.1 Classification of Numerical Methods
    • 6.2 The Application of Frequency-Domain Methods
    • 6.3 The Application of Time-Domain Methods
  • 7 Treatment of Multiple Apertures through a Digital Filter Interface
  • 8 Further Work Relevant to Shielding

7 Propagation and Crosstalk

  • 1 Introduction
  • 2 Basic Principles
  • 3 Line Parameter Calculation
    • 3.1 Analytical Methods
    • 3.2 Numerical Methods
  • 4 Representation of EM Coupling from External Fields
  • 5 Determination of the EM Field Generated by Transmission Lines
  • 6 Numerical Simulation Methods for Propagation Studies

8 Simulation of the Electromagnetic Coupling between Systems

  • 1 Overview
  • 2 Source/External Environment
  • 3 Penetration and Coupling
  • 4 Propagation and Crosstalk
  • 5 Device Susceptibility and Emission
  • 6 Numerical Simulation Methods
    • 1 The Finite-Difference Time-Domain (FD-TD) Method
    • 2 The Transmission-Line Modeling (TLM) Method
    • 3 The Method of Moments (MM)
    • 4 The Finite-Element (FE) Method

9 Effects of Electromagnetic Interference on Devices and Systems

  • 1 Immunity of Analogue Circuits
  • 2 The Immunity of Digital Circuits

Part III Interference Control Techniques

10 Shielding and Grounding .

  • 1 Equipment Screening
    • 1.1 Practical Levels of Attenuation
    • 1.2 Screening Materials
    • 1.3 Conducting Penetrations
    • 1.4 Slits, Seams, and Gasketing
    • 1.5 Damping of Resonances
    • 1.6 Measurement of Screening Effectiveness
  • 2 Cable Screening
    • 2.1 Cable Transfer Impedance
    • 2.2 Earthing of Cable Screens
    • 2.3 Cable Connectors
  • 3 Grounding
    • 3.1 Grounding in Large-Scale Systems
    • 3.2 Grounding in Self-Contained Equipment
    • 3.3 Grounding in an Environment of Interconnected Equipment

11 Filtering and Nonlinear Protective Devices

  • 1 Power-Line Filters
  • 2 Isolation
  • 3 Balancing
  • 4 Signal-Line Filters
  • 5 Nonlinear Protective Devices

12 General EMC Design Principles

  • 1 Reduction of Emissions at Source
  • 2 Reduction of Coupling Paths
    • 2.1 Operating Frequency and Rise-Time
    • 2.2 Reflections and Matching
    • 2.3 Ground Paths and Ground Planes
    • 2.4 Circuit Segregation and Placement
    • 2.5 Cable Routing
  • 3 Improvements in Immunity
    • 3.1 Immunity by Software Design
    • 3.2 Spread Spectrum Techniques
  • 4 The Management of EMC

Part IV EMC Standards and Testing

13 EMC Standards

  • 1 The Need for Standards
  • 2 The International Framework
  • 3 Civilian EMC Standards
    • 3.1 FCC Standards
    • 3.2 European Standards
    • 3.3 Other EMC Standards
    • 3.4 Sample Calculation for Conducted Emission
  • 4 Military Standards
    • 4.1 Military Standard MIL-STD-461D
    • 4.2 Defense Standard DEF-STAN 59-41
  • 5 Company Standards
  • 6 EMC at Frequencies above 1 GHz
  • 7 Human Exposure Limits to EM Fields

14 EMC Measurements and Testing

  • 1 EMC Measurement Techniques
  • 2 Measurement Tools
    • 2.1 Sources
    • 2.2 Receivers
    • 2.3 Field Sensors
    • 2.4 Antennas
    • 2.5 Assorted Instrumentation
  • 3 Test Environments
    • 3.1 Open-Area Test Sites
    • 3.2 Screened Rooms
    • 3.3 Reverberating Chambers
    • 3.4 Special EMC Test Cells

Part V EMC in Systems Design

15 EMC and Signal Integrity (SI)

  • 1 Introduction
  • 2 Transmission Lines as Interconnects
  • 3 Board and Chip Level EMC
  • 3.1 Simultaneous Switching Noise (SSN)
  • 3.2 Physical Models
  • 3.3 Behavioral Models

16 EMC and Wireless Technologies

  • 1 The Efficient Use of the Frequency Spectrum
  • 2 EMC, Interoperability, and Coexistence
  • 3 Specifications and Alliances
  • 4 Conclusions

17 EMC and Broadband Technologies

  • 1 Transmission of High-Frequency Signals over Telephone and Power Networks
  • 2 EMC and Digital Subscriber Lines (xDSL)
  • 3 EMC and Power Line Telecommunications (PLT)
  • 4 Regulatory Framework for Emissions from xDSL/PLT and Related Technologies

18 EMC and Safety

19 Statistical EMC

  • 1 Introduction
  • 2 The Basic Stochastic Problem
  • 3 A Selection of Statistical Approaches to Complex EMC Problems

 


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Updated: Sunday, 2015-07-19 18:51 PST