# Antenna Theory and Applications

# Antenna Theory and Applications

ISBN: 978-1-119-94521-5

Jan 2012

280 pages

$72.99

## Description

**This comprehensive text on antenna theory explains the origin of radiation and discusses antenna parameters in-depth**

This book offers an in-depth coverage of fundamental antenna theory, and shows how to apply this in practice. The author discusses electromagnetic radiation and antenna characteristics such as impedance, radiation pattern, polarization, gain and efficiency. In addition, the book provides readers with the necessary tools for analyzing complex antennas and for designing new ones. Furthermore, a refresher chapter on vector algebra, including gradient, divergence and curl operation is included. Throughout the book ample examples of employing the derived theory are given and all chapters are concluded with problems, giving the reader the opportunity to test his/her acquired knowledge.

Key Features:

- Covers the mathematical and physical background that is needed to understand electromagnetic radiation and antennas
- Discusses the origin of radiation and provides an in-depth explanation of antenna parameters
- Explores all the necessary steps in antenna analysis allowing the reader to understand and analyze new antenna structures
- Contains a chapter on vector algebra, which is often a stumbling block for learners in this field
- Includes examples and a list of problems at the end of each chapter
- Accompanied by a website containing solutions to the problems (for instructors) and CST modeling files (www.wiley.com/go/visser_antennas

This book will serve as an invaluable reference for advanced (last year Bsc, Msc) students in antenna and RF engineering, wireless communications, electrical engineering, radio engineers and other professionals needing a reference on antenna theory. It will also be of interest to advanced/senior radio engineers, designers and developers.

## Related Resources

**Preface ix**

**Acknowledgements xi**

**List of Abbreviations xiii**

**1 Introduction 1**

1.1 The Early History of Antennas 1

1.2 Antennas and Electromagnetic Radiation 2

*1.2.1 Electromagnetic Radiation* 2

*1.2.2 Short Wire Dipole Radiation* 5

1.3 The Modern History of Antennas 6

1.4 Frequency Spectrum and Antenna Types 8

*1.4.1 Dipole Antennas* 8

*1.4.2 Loop Antennas* 9

*1.4.3 Aperture Antennas* 10

*1.4.4 Reflector Antennas* 10

*1.4.5 Array Antennas* 11

*1.4.6 Modern Antennas* 11

1.5 Organization of the Book 12

1.6 Problems 13

References 13

**2 Antenna System-Level Performance Parameters 15**

2.1 Radiation Pattern 15

*2.1.1 Field Regions* 16

*2.1.2 Three-Dimensional Radiation Pattern* 17

*2.1.3 Planar Cuts* 19

*2.1.4 Power Patterns* 22

*2.1.5 Directivity and Gain* 25

*2.1.6 Antenna Beamwidth* 28

2.2 Antenna Impedance and Bandwidth 29

2.3 Polarization 32

*2.3.1 Elliptical Polarization* 33

*2.3.2 Circular Polarization* 35

*2.3.3 Linear Polarization* 35

*2.3.4 Axial Ratio* 36

2.4 Antenna Effective Area and Vector Effective Length 38

*2.4.1 Effective Area* 38

*2.4.2 Vector Effective Length* 40

2.5 Radio Equation 41

2.6 Radar Equation 43

*2.6.1 Radar Cross-Section* 44

2.7 Problems 46

References 47

**3 Vector Analysis 49**

3.1 Addition and Subtraction 49

3.2 Products 50

*3.2.1 Scalar Product or Dot Product* 50

*3.2.2 Vector Product or Cross Product* 51

*3.2.3 Triple Product* 52

3.3 Differentiation 53

*3.3.1 Gradient* 54

*3.3.2 Divergence* 55

*3.3.3 Curl* 57

3.4 Problems 61

**4 Radiated Fields 63**

4.1 Maxwell Equations 63

4.2 Vector Potential 64

4.3 Far-Field Approximations 69

*4.3.1 Magnetic Field* 69

*4.3.2 Electric Field* 73

4.4 Reciprocity 75

*4.4.1 Lorentz Reciprocity Theorem* 75

*4.4.2 Antenna Reciprocity* 77

4.5 Problems 79

References 79

**5 Dipole Antennas 81**

5.1 Elementary Dipole 81

*5.1.1 Radiation* 82

*5.1.2 Input Impedance* 86

5.2 Non-Infinitesimal Dipole Antenna 87

*5.2.1 Radiation* 87

*5.2.2 Input Impedance* 96

5.3 Printed Monopole and Inverted-F Antennas 97

*5.3.1 Application of Theory* 98

*5.3.2 Planar Monopole Antenna Design* 99

*5.3.3 Printed UWB Antenna Design* 105

*5.3.4 Miniature Monopole with Cable Current Suppression* 113

*5.3.5 Inverted-F Antenna Design* 120

5.4 Problems 128

References 129

**6 Loop Antennas 131**

6.1 General Constant Current Loop 131

*6.1.1 Radiation* 132

*6.1.2 Input Impedance* 136

*6.1.3 Small Loop Antenna* 137

*6.1.4 Comparison of Short Dipole and Small Loop Antenna* 138

6.2 Printed Loop Antenna 139

*6.2.1 Application of Theory* 139

*6.2.2 Design of a Printed Loop Antenna* 143

6.3 Problems 149

References 152

**7 Aperture Antennas 153**

7.1 Magnetic Sources 154

7.2 Uniqueness Theorem 156

7.3 Equivalence Principle 158

7.4 Radiated Fields 160

7.5 Uniform Distribution in a Rectangular Aperture 161

7.6 Uniform Distribution in a Circular Aperture 166

7.7 Microstrip Antennas 170

*7.7.1 Application of Theory* 172

*7.7.2 Design of a Linearly Polarized Microstrip Antenna* 175

*7.7.3 Design of a Circularly Polarized Microstrip Antenna* 179

7.8 Problems 185

References 188

**8 Array Antennas 189**

8.1 A Linear Array of Non-Isotropic Point-Source Radiators 189

8.2 Array Factor 195

8.3 Side Lobes and Grating Lobes 195

*8.3.1 Side-Lobe Level* 196

*8.3.2 Grating Lobes* 196

8.4 Linear Phase Taper 197

8.5 Grating Lobes 202

8.6 Special Topics 203

*8.6.1 Mutual Coupling* 203

*8.6.2 Antenna Diversity* 212

*8.6.3 Sequential Rotation and Phasing* 213

8.7 Array Antenna Design 217

*8.7.1 Theory* 220

*8.7.2 A Linear Microstrip Patch Array Antenna* 221

8.8 Problems 229

References 230

**Appendix A Effective Aperture and Directivity 231**

**Appendix B Vector Formulas 235**

**Appendix C Complex Analysis 237**

C.1 Complex Numbers 237

C.2 Use of Complex Variables 240

**Appendix D Physical Constants and Material Parameters 243**

References 244

**Appendix E Two-Port Network Parameters 245**

**Appendix F Transmission Line Theory 249**

F.1 Distributed Parameters 249

F.2 Guided Waves 252

*F.2.1 VSWR and Reflection Factor* 254

*F.2.2 Impedance and Relative Impedance* 254

F.3 Input Impedance of a Transmission Line 255

F.4 Terminated Lossless Transmission Line 255

*F.4.1 Matched Load* 255

*F.4.2 Short Circuit* 256

*F.4.3 Open Circuit* 256

*F.4.4 Imaginary Unit Termination* 257

*F.4.5 Real Termination* 257

F.5 Quarter Wavelength Impedance Transformer 257

**Appendix G Coplanar Waveguide (CPW) 259**

References 260

**Index 261**

“This book is a good reference for advanced students in antenna and RF engineering, wireless communications, electrical engineering, radio engineers and other professionals needing a reference on antenna theory. It will also be of interest to advanced or senior radio engineers, designers and developers as a practical guide and reference. It assumes knowledge of electromagnetic theory and vector analysis but is a good, compact reference book for antennas.” (*Microwave Journal*, 1 January 2013)

- Covers the mathematical and physical background that is needed to understand electromagnetic radiation and antennas
- Discusses the origin of radiation and provides an in-depth explanation of antenna parameters
- Explores all the necessary steps in antenna analysis allowing the reader to understand and analyze new antenna structures
- Contains a chapter on vector algebra, which is often a stumbling block for learners in this field
- Includes examples and a list of problems at the end of each chapter
- Accompanied by a website containing solutions to the problems (for instructors) and CST modeling files (www.wiley.com/go/visser_antennas