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Preface to the Second Edition

Since the publication of the first edition of this book in 2008, it has attracted a lot of attention from university students, professors, researchers as well as engineers in the industry. The book has been adopted by many universities around the world as a textbook for undergraduate and postgraduate teaching and used as a reference book for antenna research and designs. It was translated to Korean as a major antenna book in 2014. The main attraction and success of the book are its distinct and unique feature from other well‐known antenna books: it has integrated the antenna theory with real‐world examples from the past to the present into one volume without excessive mathematics. This feature has been maintained in this new edition.

Based on the success of the first edition, this edition has provided a better coverage in many important areas and added some recent and latest developments in antenna theory and practice. In particular, the theory of characteristic modes (Section 6.5) for antenna design and analysis, new materials (e.g. composite materials, metamaterials, and meta‐surfaces in Section 7.1), fabrication processes (Section 7.2), and advanced measurement methods for antennas (Section 7.3). MIMO antennas, automotive antennas, and reflector antennas have been added to Special Topics in Chapter 8 to reflect some of the current hot topics. Every chapter has been updated with the latest information. Of course, the mistakes and errors identified in the first edition have also been corrected. As a result, the number of pages is increased significantly from 360 to over 500.

As an essential element of a radio system, the antenna has always been an interesting but difficult subject for radio‐frequency (RF) engineering students and engineers. Many good books on antennas have been published over the years, and some of them were used as our major references.

This book is different from other antenna books. It is especially designed for the people who are relatively new to antennas but would like to learn this subject from the basics to advanced antenna analyses, designs, and measurements within a relatively short period of time. In order to gain a comprehensive understanding of antennas, one must also know transmission lines and radio propagation. At the moment, people often have to read a number of different books, which may not be well correlated. Thus, it is not the most efficient way to study this subject. In this book, we put all the necessary information about antennas into a single manuscript and try to examine the antenna from both the circuit point of view and the field point of view. The book covers the basic transmission line and radio propagation theories, which are then used to gain a good understanding of antenna basics and theory. Various antennas are examined, and design examples are presented. Particular attention is given to modern computer‐aided antenna designs. Both basic and advanced computer software packages are used as examples to illustrate how they can be used for antenna analysis and design. Antenna materials, fabrication processes, measurement theory, and techniques are also addressed. Some special topics on the latest antenna development are covered in the final chapter.

The book material is mainly based on a successful short course on antennas for practicing professionals at the University of Oxford and the Antennas module for the students at the University of Liverpool. The book covers almost all aspects about antennas, especially important and timely issues involving modern practical antenna design and theory. Many examples and questions are given in each chapter. It is an ideal textbook for university antenna course, professional training course, and self‐study. It is also a valuable reference for engineers and researchers who work with RF engineering, radar and radio communications. The organization of this book is as follows:

 Chapter 1: Introduction. The objective of this chapter is to introduce the concept of antenna and review essential mathematics and electromagnetics, especially Maxwell’s equations. Material properties (permittivity, permeability, and conductivity) are discussed, and some common ones are presented in tables.

 Chapter 2: Circuit Concepts and Transmission Lines. The concepts of lumped and distributed systems are established. The focus is placed on the fundamentals and characteristics of transmission lines. A comprehensive coverage on Smith chart, bandwidth, and impedance match techniques is provided in this edition. A wide range of conventional and new transmission lines and connectors are introduced and compared.

 Chapter 3: Field Concepts and Radiowaves. Field concepts, including plane wave, intrinsic impedance, and polarization, are introduced and followed by a discussion on radio propagation mechanisms and radiowave propagation characteristics in various media. Some basic radio propagation models are introduced, and circuit concepts and field concepts are compared at the end of this chapter.

 Chapter 4: Antenna Basics. The essential and important parameters of an antenna (such as the radiation pattern, gain, and input impedance) are addressed from both the circuit point of view and field point of view. Through this chapter, you will become familiar with antenna language, understand how antennas work, and know what the main design considerations are.

 Chapter 5: Popular Antennas. In this long chapter, some of the most popular antennas (wire‐type, aperture‐type, and array antennas) are introduced and analyzed using relevant antenna theories. The aim is to see why they have become popular, what their major features and properties are (including advantages and disadvantages), and how they should be designed.

 Chapter 6: Computer‐Aided Antenna Design and Analysis. The aim of this special and unique chapter is to give a good review of antenna modeling methods and software development, introduce the basic theory behind computer simulation tools, and demonstrate how to use industry standard software to analyze and design antennas. Two software packages (one is simple and free) are presented with step‐by‐step illustrations. The theory of characteristic modes (TCM) is introduced, and a patch antenna is employed as an example to illustrate how to use TCM for antenna design and analysis.

 Chapter 7: Antenna Materials, Fabrication, and Measurements. This is another practical chapter to address three important issues: what materials are suitable for antennas, how to make an antenna, and then how to conduct antenna measurements accurately and efficiently. Some popular measurement equipment and facilities are introduced and discussed. A good overview of antenna measurement systems is provided with real‐world examples. Some latest measurement techniques and problems are also presented and discussed.

 Chapter 8: Special Topics. This final chapter presents some of the latest important developments in antennas. It covers electrically small antennas, mobile terminal and base‐station antennas, diversity and MIMO antennas, RFID antennas, multiband and broadband antennas, reconfigurable antennas, automotive antennas, and reflector antennas. Relevant theory, design techniques, and practical examples are provided for in‐depth understanding.

On completion of this book, the reader should be ready to conduct advanced antenna design, analysis, and measurements and ready to become an antenna researcher and engineer.

I am very grateful to the many individuals who have provided great contributions, comments, suggestions, and assistance to make this much improved second edition a reality. In particular, I would like to extend my sincere appreciation to:

1 Dr Kevin Boyle from Qualcomm, who has contributed significantly to the first edition as coauthor and provided many good suggestions, corrections, and references to the second edition. It is a pity that his new job has made it impossible for him to directly contribute to the second edition;

2 Mr Lars Foged, Scientific Director of MVG, who is a well‐known measurement expert and has contributed to various parts and a section on antenna measurements in Chapter 7;

3 Prof Tony Brown, a leading antenna expert from Manchester University, who has contributed a new section on reflector antennas in Chapter 8;

4 Prof Tae‐Hoon Yoo at Dongyang Mirae University for having translated the book into Korean and provided many great suggestions and feedbacks on how to make the second edition better;

5 Dr Hanyang Wang, Chief Antenna Expert of Huawei, for inspiring discussions on industrial practices in antenna designs, fabrication, and measurements.

6 My students: Ahmed Alieldin, Lyuwei Chen, Qian Xu, Sheng Yuan, Chaoyun Song, Jiayou Wang, Shahzad Maqbool, Barry Cheeseman, Yang Lu, and many other current and past students at the University of Liverpool for constructive feedbacks and production of figures;

7 The individuals and organizations who have provided us with their figures or allowed us to reproduce their figures;

8 A special one who has kindly provided a list of corrections of the first edition via John Wiley, but I was not given his/her name;

9 The team at John Wiley who have provided the guidance and great support throughout the process.

Prof Yi Huang

Chair in Wireless Engineering

The University of Liverpool, UK

Yi.Huang@IEEE.org

January 2021