Antennas are part of every radar, every communications system, and every electronic warfare system. Therefore antennas are an important technical subject. The number of antenna books that have been published in the last 5 years alone attest to this fact. But why another book about antennas? What does this book offer that is different from all the others? The answer is: accessibility. Most of the technical literature on antennas is written for those with extensive backgrounds in electromagnetic theory and familiarity with the mathematical language of vector analysis, differential equations, and special functions. This puts much of the antenna literature out of reach for the nonspecialist who needs to understand the subject but cannot afford the time required to become familiar with all the background material. With the rapid expansion of technical knowledge, the number of engi­ neering students who find themselves attracted to "classical" subjects, such as electromagnetic theory, is on the decline, making it increasingly difficult to train engineers in areas involving antennas. Some authors in other technical fields have recognized this problem. For example, books on solid-state elec­ tronic devices that do not require an extensive background in quantum me­ chanics are available, useful, and informative. This book fulfills a similar Ileed in the area of antennas.