# Preface to Eighth Edition

Building on the core content and style of its predecessor, this eighth edition (8/e) of Applied Electromagnetics includes features designed to help students develop deep understanding of electromagnetic concepts and applications. Prominent among them is a set of 52 web-based simulation modules* that allow the user to interactively analyze and design transmission line circuits; generate spatial patterns of the electric and magnetic fields induced by charges and currents; visualize in 2-D and 3-D space how the gradient, divergence, and curl operate on spatial functions; observe the temporal and spatial waveforms of plane waves propagating in lossless and lossy media; calculate and display field distributions inside a rectangular waveguide; and generate radiation patterns for linear antennas and parabolic dishes. These are valuable learning tools; we encourage students to use them and urge instructors to incorporate them into their lecture materials and homework assignments.

Additionally, by enhancing the book’s graphs and illustrations and by expanding the scope of topics of the Technology Briefs, additional bridges between electromagnetic fundamentals and their countless engineering and scientific applications are established.

# New To This Edition

- Additional exercises

- Updated Technology Briefs

- Enhanced figures and images

- New/updated end-of-chapter problems

# Acknowledgments

As authors, we were blessed to have worked on this book with the best team of professionals: Richard Carnes, Leland Pierce, Janice Richards, Rose Kernan, and Paul Mailhot. We are exceedingly grateful for their superb support and unwavering dedication to the project.

We enjoyed working on this book. We hope you enjoy learning from it.

Fawwaz T. Ulaby

Umberto Ravaioli

# Content

This book begins by building a bridge between what should be familiar to a third-year electrical engineering student and the electromagnetics (EM) material covered in the book. Prior to enrolling in an EM course, a typical student will have taken one or more courses in circuits. He or she should be familiar with circuit analysis, Ohm’s law, Kirchhoff’s current and voltage laws, and related topics.

Transmission lines constitute a natural bridge between electric circuits and electromagnetics. Without having to deal with vectors or fields, the student will use already familiar concepts to learn about wave motion, the reflection and transmission of power, phasors, impedance matching, and many of the properties of wave propagation in a guided structure. All of these newly learned concepts will prove invaluable later (in Chapters 7 through 9) and will facilitate the learning of how plane waves propagate in free space and in material media. Transmission lines are covered in Chapter 2, which is preceded in Chapter 1 with reviews of complex numbers and phasor analysis.

The next part of this book, contained in Chapters 3 through 5, covers vector analysis, electrostatics, and magnetostatics. The electrostatics chapter begins with Maxwell’s equations for the time-varying case, which are then specialized to electrostatics and magnetostatics. These chapters will provide the student with an overall framework for what is to come and show him or her why electrostatics and magnetostatics are special cases of the more general time-varying case.

Chapter 6 deals with time-varying fields and sets the stage for the material in Chapters 7 through 9. Chapter 7 covers plane-wave propagation in dielectric and conducting media, and Chapter 8 covers reflection and transmission at discontinuous boundaries and introduces the student to fiber optics, waveguides, and resonators. In Chapter 9, the student is introduced to the principles of radiation by currents flowing in wires, such as dipoles, as well as to radiation by apertures, such as a horn antenna or an opening in an opaque screen illuminated by a light source.

To give the student a taste of the wide-ranging applications of electromagnetics in today’s technological society, Chapter 10 concludes this book with presentations of two system examples: satellite communication systems and radar sensors.

The material in this book was written for a two-semester sequence of six credits, but it is possible to trim it down to generate a syllabus for a one-semester, four-credit course. The accompanying table provides syllabi for each of these options.

# Suggested Syllabi

Suggested Syllabi Full Alternative Text

# Message to the Student

The web-based interactive modules of this book were developed with you, the student, in mind. Take the time to use them in conjunction with the material in the textbook. The multiple-window feature of electronic displays makes it possible to design interactive modules with “help” buttons to guide you through the solution of a problem when needed. Video animations can show you how fields and waves propagate in time and space, how the beam of an antenna array can be made to scan electronically, and how current is induced in a circuit under the influence of a changing magnetic field. The modules are a useful resource for self-study. You can find them at the book companion website em8e.eecs.umich.edu. Use them!

# Book Companion Website

Throughout the book, we use the symbol EM to denote the book companion website em8e.eecs.umich.edu, which contains a wealth of information and tons of useful tools.

# Acknowledgments

Special thanks are due to our reviewers for their valuable comments and suggestions. They include Constantine Balanis of Arizona State University, Harold Mott of the University of Alabama, David Pozar of the University of Massachusetts, S. N. Prasad of Bradley University, Robert Bond of the New Mexico Institute of Technology, Mark Robinson of the University of Colorado at Colorado Springs, and Raj Mittra of the University of Illinois. I appreciate the dedicated efforts of the staff at Prentice Hall, and I am grateful for their help in shepherding this project through the publication process in a very timely manner.

Fawwaz T. Ulaby