Antenna Analysis and Design Using FEKO

Electromagnetic Simulation Software

Atef Z. Elsherbeni Electrical Engineering and Computer Science Department,

Colorado School of Mines

Payam Nayeri Electrical Engineering and Computer Science Department,

Colorado School of Mines

C. J. Reddy EM Software & Systems (USA), Inc.

B SCITECH PUBLISHING

a n imprint of t he IET

Edison, NJ theiet.org

Contents

Preface xi Reviewer Acknowledgment xiii Author Biographies xv

1 Introduction to Antennas 1

1.1 The Basics of Antennas 1 1.2 About This Book 4

2 Wire Dipole and Monopole Antennas 7

2.1 Introduction 7 2.2 Infinitesimal, Small, and Finite Length Dipole Antennas 2.3 Dipole Antenna Full-Wave Simulation 10 2.4 Monopole Antennas and Full-Wave Simulations 19 2.5 Dipole Antennas and Wireless Power Transfer 24 2.6 Dipole Antenna Above a PEC Ground Plane 24 2.7 Dipole Antenna Near a PEC Cylinder 30 2.8 Dipole Antenna Near a PEC Sphere 32 2.9 Dipole Antenna Near a Dielectric Sphere 34 2.10 Quasi Log-Periodic Dipole Antennas 36

Exercises 39

3 Wire Loop Antennas 41

3.1 Introduction 41

3.2 Small and Large Loop Antennas 41 3.3 Circular Loop Antennas 43 3.4 Square Loop Antennas 53

VII

viii Contents

3.5 Triangular Loop Antennas 60 3.6 Loop Antennas Near a PEC Scatterer 68

Exercises 71

4 Microstrip Patch Antennas 73

4.1 Introduction 73 4.2 Patch Antenna Design and Analysis 74 4.3 Full-Wave Simulation of Patch Antennas in FEKO 76 4.4 Circularly Polarized Patch Antennas 88

Exercises 93

5 Microstrip-Based Feeding Networks 95

5.1 Introduction 95 5.2 Design of Microstrip Transmission Lines 95 5.3 The Quarter-Wavelength Transformer 99

5.4 T-Junction Power Dividers 101 5.5 Wilkinson Power Dividers 104 5.6 The Quadrature Hybrid 105

Exercises 108

6 Broadband Dipole Antennas 109

6.1 Introduction 109 6.2 Cylindrical Dipole Antennas 109 6.3 Biconical Antennas 114 6.4 Folded Dipole Antennas 118

Exercises 123

7 Traveling Wave and Broadband Antennas 127

7.1 Introduction 127 7.2 Helical Antennas 128 7.3 Yagi-Uda Antennas 137

Exercises 149

Contents

8 Frequency-Independent Antennas 153 8.1 Introduction 153 8.2 Spiral Antennas 154

8.3 Log-Periodic Antennas 160 Exercises 166

9 Horn Antennas 167 9.1 Introduction 167

9.2 Sectoral Horn Antennas 168 9.3 Pyramidal Horn Antennas 171 9.4 Conical Horn Antennas 176 9.5 A Multimode Horn Antenna: The Potter Horn 179 9.6 Corrugated Conical Horn Antenna 182

Exercises 185

10 Reflector Antennas 187

10.1 Introduction 187 10.2 Corner Reflector Antennas 187 10.3 Design and Analysis of Parabolic Reflector Antennas 191 10.4 Design and Analysis of Spherical Reflector Antennas 201

Exercises 207

11 Antenna Arrays 209 11.1 Introduction 209

11.2 Basics of Antenna Arrays 210 11.3 Two-Element Dipole Arrays 212 11.4 A^-Element Uniform-Amplitude Linear Dipole Arrays 215 11.5 TV-Element Linear Dipole Arrays with Nonuniform Amplitude 220 11.6 Planar Antenna Arrays 222

Exercises 228

References 231

Index 233