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เนื้อหาย่อ : Over the years, I have developed a familiarity with this book in its various editions, having learned from it, referred to it, and taught from it. The second edition was used in my first electromagnetics course as a junior during the early '70's. Its simple and easy-to-read style convinced me that this material could be learned, and it helped to confirm my latent belief at the time that my specialty would lie in this direction. Later, it was not surprising to see my own students coming to me with heavily-marked copies, asking for help on the drill problems, and taking a more active interest in the subject than I usually observed. So, when approached to be the new co-author, and asked what I would do to change the book, my initial feeling was--nothing. Further reflection brought to mind earlier wishes for more material on waves and transmission lines. As a result, Chapters 1 to 10 are original, while 11 to 14 have been revised, and contain new material. A conversation with Bill Hayt at the project's beginning promised the start of what I thought would be a good working relationship. The rapport was immediate. His declining health prevented his active participation, but we seemed to be in general agreement on the approach to a revision. Although I barely knew him, his death, occurring a short time later, deeply affected me in the sense that someone that I greatly respected was gone, along with the promise of a good friendship. My approach to the revision has been as if he were still here. In the front of my mind was the wish to write and incorporate the new material in a manner that he would have approved, and which would have been consistent with the original objectives and theme of the text. Much more could have been done, but at the risk of losing the book's identity and possibly its appeal. Before their deaths, Bill Hayt and Jack Kemmerly completed an entirely new set of drill problems and end-of-chapter problems for the existing material at that time, up to and including the transmission lines chapter. These have been incorporated, along with my own problems that pertain to the new topics. The other revisions are summarized as follows: The original chapter on plane waves has now become two. The first (Chapter 11) is concerned with the development of the uniform plane wave and the treatment wave propagation in various media. These include lossy materials, where propagation and loss are now modeled in a general way using the complex permittivity. Conductive media are presented as special cases, as are materials that exhibit electronic or molecular resonances. A new appendix provides background on resonant media. A new section on wave polarization is also included. Chapter 12 deals with wave reflection at single and multiple interfaces, and at oblique incidence angles. An additional section on dispersive media has been added, which introduces the concepts of group velo- city and group dispersion. The effect of pulse broadening arising from group dispersion is treated at an elementary level. Chapter 13 is essentially the old transmission lines chapter, but with a new section on transients. Chapter 14 is intended as an introduction to waveguides and antennas, in which the underlying