电磁学及其应用 第5版PDF电子书下载

1 Introduction 1

1-1 Electromagnetics: Its Importance 1

1-2 Dimensions and Units 2

1-3 Fundamental and Secondary Units 2

1-4 How to Read the Symbols and Notation 5

1-5 Equation and Problem Numbering 7

1-6 Vector Analysis 8

Introduction 8

Scalars and Vectors 9

Vector Addition and Subtraction 9

Multiplication and Division of a Vector by a Scalar 11

Rectangular Coordinates and the Resolution of a Vector into Components 12

The Scalar or Dot Product of Two Vectors 13

The Line Integral 15

The Surface Integral 18

The Volume Integral 21

Vector or Cross-Product of Two Vectors 22

1-7 Inroduction to Coordinate Systems 24

Coordinate Tables 27

Problems 30

2 Electric and Magnetic Fields 35

2-1 Introduction 35

2-2 Electric Fields 35

Electric Charge Q and Electric Field E 35

2-3 Electrie Potential V and Its Gradient E 39

Superposition of Potential 44

2-4 Electric Field Streamlines and Equipotential Contours; Orthogonality 47

2-5 Multiconductor Transmission Lines 48

Line Charges 48

2-6 Electric Flux and Electric Flux Density (or Displacement): Gauss s Law 51

Surface Charge, Uniform Case 51

Surface Charge, Nonuniform Case 52

Volume Charge and Gauss s Law 54

2-7 Divergence 56

Poisson s and Laplace s Equations 58

2-8 Boundary Conditions; Dielectric Media 59

2-9 Capacitors and Capacitance;Capacitor Cells 61

Capacitor Energy and Energy Density 64

2-10 Twin-Strip and Microstrip Transmission Lines 65

2-11 Electric Currents 68

Electric Current and Current Density 68

Resistance and Conductance;Resistivity and Conductivity 70

Ohm s Law 71

Ohm s Law at a Point and Current Density 72

Power and Joule s Law 73

Dielectrics, Conductors, and Semiconductors Compared-An Overview 73

Conductor Cells 76

Boundary Conditions; Conducting Media 79

Potential and emf 80

2-12 Magnetic Fields of Electric Currents 81

Magnetic Flux Ψm and Magnetic Flux Density B; Gauss s Law 86

Lorentz Force or Motor Equation 87

Inductance, Inductors, Energy, and Energy Density 89

Inductor Energy and Energy Density 92

Inductor Cells 92

2-13 Changing Magnetic Fields, Induction, and Faraday s Law 96

2-14 Examples of Induction 99

Motion and Time-Changing Induction 99

Coupling, Cross Talk, and Mutual Inductance 105

2-15 Curl 108

2-16 Maxwell s Equations 112

Problems 115

3 Transmission Lines 119

3-1 Introduction 119

3-2 Circuit Theory 119

3-3 Field Theory 123

The Microstrip Transmission Line 127

Transmission Line Impedance Formulas 130

Energy, Power, and Poynting Vector 133

3-4 The Terminated Uniform Transmission Line and VSWR 137

Impedance Matching; the Smith Chart 145

Using a Smith Chart 146

Stub Tuning 151

3-5 Bandwidth 155

3-6 Pulses and Transients 162

The λ/4 Transformer 162

Important Conclusions 165

Problems 166

4 Wave Propagation, Attenuation, Polarization, Reflection, Refraction, and Diffraction 169

4-1 Introduction 169

4-2 Waves in Space 169

4-3 Traveling Waves and Standing Waves 175

4-4 Conductors and Dielectrics 178

4-5 Conducting Media and Lossy Lines 181

4-6 Dielectric Hysteresis and Dielectric Loss 187

4-7 Plane Waves at Interfaces and Analogous Transmission Lines 189

Wave Absorption with Conducting Sheet(Salisbury Sheet) 196

Wave Absorption with Ferrite-Titanate Medium 197

4-8 Relative Phase Velocity and Index of Refraction 201

4-9 Group Velocity 203

4-10 Power and Energy Relations 207

4-11 Linear, Elliptical, and Circular Polarization 211

4-12 Poynting Vector for Elliptically and Circularly Polarized Waves 214

4-13 The Polarization Ellipse and the Poincaré Sphere 215

4-14 Oblique Incidence: Reflection and Refraction 219

Perpendicular Case(EI) 219

Parallel Case(EII) 224

4-15 Elliptically Polarized Plane Wave, Oblique Incidence 226

4-16 Huygens Principle and Physical Optics; Diffraction 231

Projects 237

Problems 239

5 Antennas, Radiation, and Wireless Systems 247

5-1 Introduction 247

5-2 Basic Antenna Parameters 247

5-3 Arrays 260

Two Isotropic Point Sources 260

Pattern Multiplication 260

Binomial Array 262

Linear Arrays of n Isotropic Point Sources of Equal Amplitude and Spacings 264

5-4 Retarded Potentials 275

5-5 The Short Dipole Antenna and Its Radiation Resistance 276

5-6 Pattern and Radiation Resistance of λ/2 and 3λ/2 Dipoles 285

5-7 Broadside Array 287

5-8 Fields of λ/2 Dipole Antenna 291

5-9 Antenna Types 292

Loops, Dipoles, and Slots 292

Opened-Out Coaxial Antennas 294

Opened-Out Two-Conductor Antennas 294

Opened-Out Waveguide Antennas 294

Flat-Sheet Reflector Antennas 298

Paranbolic Dish and Dielectric Lens Antennas 298

End-Fire Antennas: Polyrod, Yagi-Uda, and Helical 301

Broad-Bandwidth Antennas: Conical Spiral, Log-Periodic, and 3-in-I 305

Patch Antennas 307

Arrays of Dipoles and Slots;Frequency Selective Surfaces(FSS) 308

5-10 Radion Link and Friis Formula 308

5-11 Antenna Temperature, Signal-to-Noise Ratio, and Remots Sensing 309

Note: Ratios and Decibels 314

5-12 Radar and Radar Cross-Section 318

Pulse Doppler Weather Radar 323

The Corner Reflector 324

5-13 Global Position Satellites and Relatiyity 327

5-14 Far Field, Near Field, and Fourier Transform 329

5-15 Earth-Based, Airborne, and Spaceborne Cellular Systems 332

5-16 Absorption by Atmosphere and Foliage 335

Projects 340

Problems 343

6 Electrodynamics 357

6-1 Introduction 357

6-2 Charged Particles Moving in Electric Fields 357

6-3 The Cathode-Ray Tube(CRT);Electrical Deflection 359

6-4 Charged Particles Moving in a Static Magnetic Field 361

Particle Radius 363

Gyrofrequency 364

6-5 Cathode-Ray Tube; Magnetic Deflection 365

6-6 Rotary Motor or Generator 367

6-7 Linear Motor 369

6-8 Hall-Effect Generator 370

6-9 Moving Conductor in a Static Magnetic Field 373

6-10 The Magnetic Brake 374

Problems 376

7 Dielectric and Magnetic Materials 379

7-1 Introduction 379

7-2 Homogeneity, Linearity, and Isotropy 379

7-3 Table of Permittivities 380

7-4 The Electric Field in a Dielectric 381

7-5 The Electric Dipole and Electric-Dipole Moment 381

7-6 Polarization 384

7-7 Boundary Relations 389

7-8 Table of Boundary Relations 392

7-9 Dielectric Strength 392

7-10 Energy and Energy Density 393

7-11 The Atomic Loop 396

7-12 Magnetic Dipoles, Loops, and Solenoids 399

7-13 Magnetic Materials 404

7-14 Magnetic Dipoles and Magnetization 406

7-15 Uniformly Magnetized Rod and Equivalent Air-Core Solenoid 409

7-16 Boundary Relations 412

7-17 Ferromagnetism 415

7-18 Magnetization Curves 418

7-19 Hysteresis 424

7-20 Energy in a Magnet 426

7-21 Permanent Magnets 427

7-22 Table of Permanent Magnetic Materials 429

7-23 Demagnetization 430

7-24 Gapless Circuit 434

7-25 Magnetic Circuit with Air Gap 435

7-26 Magnetic Gap Force 437

7-27 Permanent Magnet with Gap 438

7-28 Altermating-Current Behavior of Ferromagnetic Materials 441

7-29 Eddy Currents 443

Problems 443

8 Waveguides, Resonators, and Fiber Optics 447

8-1 Introduction 447

8-2 Circuits, Lines, and Guides: A Comparison 447

8-3 TE Mode Wave in the Infinite-Parallel-Plane Transmission Line or Guide 448

8-4 The Hollow Rectangular Waveguide 456

8-5 The Hollow Cylindrical Waveguide 468

8-6 Hollow Waveguides of Other Cross-Section 472

8-7 Waveguide Devices 474

8-8 Waves Traveling Parallel to a Plane Boundary 475

8-9 Open Waveguides 480

8-10 Dielectric Sheet Waveguides 483

8-11 Dielectric Fiber and Rod Waveguides: Fiber Optics 487

8-12 Cavity Resonators 491

Project 499

Problems 500

9 Bioelectromagnetics 501

9-1 Introduction 501

9-2 The Axon: An Active, Lossless, Shielded, Noiseless Transmission Line 501

9-3 Retinal Optic Fibers 503

9-4 Heart Dipole Field 506

9-5 Defibrillators and Pacemakers 507

9-6 Biological Fields 509

9-7 Electromagnetic Hazards and the Environment 512

Projects 516

Solar Power to Food 518

Problems 519

Solar Power Problems 520

References 520

10 Electromagnetic Effects in High-Speed Digital Systems 521

10-1 Introduction 521

SceneI:A Strangely Behaving Reset Signal on a PC Card 521

SceneII:CD Player on Airplane Interferes with the Navigation System 522

10-2 Two Viewpoints: Lumped or Distributed 522

10-3 Distributed Systems 522

Speed and Distance 522

Rise Time and Length; Lumped versus Distributed Circuits 523

Knee Frequency 526

Review of Transmission Line Theory 527

Reflections in the Presence of Capactitance 530

Terminations 533

10-4 Inductance and Capacitance 534

How Circuit Boards Are Made 534

Cross Talk 537

10-5 Electromagnetic Interference 539

Problems 542

11 Numerical Methods 547

11-1 Introduction 547

11-2 Laplace s Equation in Rectangular Coordinates; Separation of Variables 548

11-3 Example 11-1: The Parallel-Plate Capacitor 550

11-4 Repetitive Laplace Solution or Finite Difference Method 552

11-5 Example 11-2: The Infinite Square Trough with Lid by Repetitive Laplace 554

11-6 Example 11-3: Infinite Square Trough with Different Potentials on All Four Sides 556

11-7 Line Charge Distribution: The Integral Equation and the Moment Method(MM) 558

11-8 The Generalized Multipole Technique(GMT) 560

11-9 Finite Difference-Time Domain(FD-TD)Technique 560

11-10 Finite Element Method(FEM) 563

11-11 Continuous Wave(CW)Reflections and FEM 565

Problems 567

Appendixes 569

A Units, Constants, and Other Useful Reltions 569

A-1 Fundamental, Mechanical, Electrical, and Magnetic Units 570

A-2 Trigonometric, Hyperbolic, Logarithmic, and Other Relations 576

A-3 Glyphs(Nonalphabetic Pictograph Symbols) 579

B Field Maps, Laplace s Equation, Full Vector Notation 581

Field Mapping 581

Graphical Solution 582

Full Vector Notation 585

C Computer Programs 589

1: ZX 590

2: VSWR 590

3: Bouncing Pulses 590

4: Traveling waves 590

5: Ground bounce 590

6: ARRAYPATGAIN 590

7: REPLA 590

8: Charged Plates 590

9: Post 590

10: Lossy line 590

11: V-LEVEL 590

12: SMITH CHART 590

13: QWT 590

D Project Equipment 591

E Answers 593

Index 601

Symbols, prefixes and abbreviation 619

Constants and conversions 621