List of Contributors xi
 
Preface xii
 
Acknowledgements xv
 
1 Introduction 1
Satish K. Sharma and Jia-Chi S. Chieh
 
1.1 Introduction 1
 
1.2 Antenna: an Integral Component of Wireless Communications 1
 
1.3 Antenna Performance Parameters 2
 
1.4 Antenna Types 2
 
1.5 Multifunctional Antennas 3
 
1.6 Reconfigurable Antennas 6
 
1.7 Frequency Agile/Tunable Antenna 13
 
1.8 Antenna Measurements 17
 
1.9 Conclusion 18
 
References 18
 
2 Frequency Reconfigurable Antennas 19
Saeed I. Latif and Satish K. Sharma
 
2.1 Introduction 19
 
2.2 Mechanism of Frequency Reconfigurability 20
 
2.3 Types of FRAs 21
 
2.3.1 Frequency Reconfigurability by Switches/Tunable Components 21
 
2.3.1.1 Electrical Switches 22
 
2.3.1.2 Varactor Diodes 31
 
2.3.1.3 Micro-Electro-Mechanical-System (MEMS) Switches 40
 
2.3.1.4 Optical Switches 40
 
2.3.1.5 Ground Plane Membrane Deflection 43
 
2.3.2 Frequency Reconfigurability Using Special Materials 43
 
2.3.2.1 Liquid Crystals 45
 
2.3.2.2 Graphene 47
 
2.3.3 Frequency Reconfigurability by Mechanical Changes 49
 
2.3.3.1 Actuators 49
 
2.3.3.2 Motors 50
 
2.3.4 Frequency Reconfigurability Using Special Shapes 53
 
2.3.4.1 Origami Antennas 53
 
2.3.4.2 Fractal Shapes 54
 
2.4 FRAs in the Future: Applications in Emerging Technologies 58
 
2.5 Conclusion 59
 
References 59
 
3 Radiation Pattern Reconfigurable Antennas 67
Sima Noghanian and Satish K. Sharma
 
3.1 Introduction 67
 
3.2 Pattern Reconfigurable by Electronically Changing Antenna Elements 67
 
3.3 Pattern Reconfigurable by Electronically Changing Feeding Network 88
 
3.4 Mechanically Controlled Pattern Reconfigurable Antennas 90
 
3.5 Arrays and Optimizations 98
 
3.6 Reconfigurable Wearable and Implanted Antennas 110
 
3.7 Conclusion 119
 
References 119
 
4 Polarization Reconfigurable Antennas 122
Behrouz Babakhani and Satish K. Sharma
 
4.1 Introduction 122
 
4.2 Polarization Reconfiguration Mechanism Using RF Switches 124
 
4.3 Solid-State RF Switch-Based Polarization Reconfigurable Antenna 125
 
4.4 Mechanical and Micro-electro-mechanical (MEMS) RF Switch-Based Antennas 140
 
4.5 Switchable Feed Network-Based Polarization Reconfiguration 148
 
4.6 Polarization Reconfigurable Antennas Using Metasurface 157
 
4.7 Other Methods to Create Polarization Reconfigurable Antennas 162
 
4.8 Conclusion 169
 
References 169
 
5 Liquid Metal, Piezoelectric, and RF MEMS-Based Reconfigurable Antennas 172
Jia-Chi S. Chieh and Satish K. Sharma
 
5.1 Introduction 172
 
5.2 Liquid Metal - Frequency Reconfigurable Antennas 172
 
5.3 Liquid Metal - Pattern Reconfigurable Antennas 175
 
5.4 Liquid Metal - Directivity Reconfigurable Antennas 182
 
5.5 Piezoelectric - Pattern Reconfigurable Array 184
 
5.6 RF MEMS - Frequency Reconfigurable 189
 
5.7 RF MEMS - Polarization Reconfigurable 191
 
5.8 RF MEMS - Pattern Reconfigurable 194
 
5.9 Conclusion 196
 
References 197
 
6 Compact Reconfigurable Antennas 198
Sima Noghanian and Satish K. Sharma
 
6.1 Introduction 198
 
6.2 Reconfigurable Pixel Antenna 199
 
6.3 Compact Reconfigurable Antennas Using Fluidic 209
 
6.4 Compact Reconfigurable Antennas Using Ferrite and Magnetic Materials 213
 
6.5 Metamaterials and Metasurfaces 224