Contents
Preface...............................................................................................................................................xi
About the Authors....................................................................................................................... xiii
Abbreviations.................................................................................................................................xv
1. Introduction..............................................................................................................................1
1.1 Need for Millimeter Waves...........................................................................................1
1.2 Antennas for Cellular Communications.....................................................................4
1.3 Contrast between 4G and 5G Architectures...............................................................6
1.4 Antenna Designs for mmWave 5G Mobile Terminals and Base Stations..............9
1.4.1 Antennas for Mobile Terminals....................................................................10
1.4.2 Antennas for Base Stations............................................................................12
1.5 Antennas beyond 5G...................................................................................................13
1.6 Outline of the Book......................................................................................................13
References................................................................................................................................14
2. Conformal Antennas for Mobile Terminals.....................................................................21
2.1 Introduction..................................................................................................................21
2.2 Typical Requirements for Mobile Antennas.............................................................21
2.3 CPW-fed Wideband Corner Bent Antenna for 5G Mobile Terminals...................23
2.3.1 CPW-fed Wideband Antenna........................................................................24
2.3.2 CPW-fed Corner Bent Antenna.....................................................................30
2.3.3 CPW-fed Corner Bent Antenna with Reflector...........................................34
2.4 A wideband High Gain Conformal Antenna for mmWave 5G Smartphones....44
2.5 Design Guidelines for CPW-fed Conformal Antennas at Ka Band......................49
2.6 Conclusion....................................................................................................................50
References................................................................................................................................50
3. Flexible Antennas for Mobile Terminals..........................................................................53
3.1 Introduction..................................................................................................................53
3.2 Overview of Flexible Substrates for mmWave Applications.................................54
3.3 Corner Bent Patch Antenna for Portrait Mode........................................................56
3.4 Corner Bent Tapered Slot Antenna for Landscape Mode......................................60
3.5 Dielectric Loaded Polycarbonate-Based Vivaldi Antenna.....................................66
3.6 Conclusion....................................................................................................................71
References................................................................................................................................71
4. Compact Antennas with Pattern Diversity.......................................................................73
4.1 Introduction..................................................................................................................73
4.2 CPW-fed Conformal Folded Dipole with Pattern Diversity..................................74
4.2.1 CPW-Fed Folded Dipole................................................................................75
4.2.2 Conformal Folded Dipole Backed by Reflector..........................................83
4.3 Conformal Antennas with Pattern Diversity...........................................................92
4.3.1 Mobile Terminal Usage Modes.....................................................................92
4.3.2 Conformal Patch Antenna.............................................................................94
4.3.3 Conformal Tapered Slot Antenna.................................................................96
4.3.4 Conformal TSA with Parasitic Ellipse..........................................................99
4.3.5 Conformal Pattern Diversity.......................................................................103
4.4 Case Studies: Measurement in a Typical Indoor Environment...........................108
4.5 Conclusion.................................................................................................................. 110
References.............................................................................................................................. 111
5. Pattern Diversity Antennas for Base Stations................................................................ 115
5.1 Introduction................................................................................................................ 115
5.2 Pattern Diversity of Path Loss Compensated Antennas for 5G Base Stations......115
5.2.1 mmWave Tapered Slot Antenna................................................................. 116
5.2.2 Dielectric and Metamaterial Loaded TSA................................................. 119
5.2.3 Pattern Diversity...........................................................................................127
5.3 Path Loss Compensated Pattern Diversity Antennas with 3D Printed Radome.....131
5.3.1 3D Printed Radome for a Patch Antenna..................................................131
5.3.2 Pattern Diversity with 3D Printed Radome..............................................132
5.4 Path Loss Compensated Module with Progressive Offset ZIM..........................136
5.4.1 Central Element: Tapered Slot Antenna....................................................136
5.4.2 Spatially Modulated ZIM Loaded Antenna..............................................139
5.4.3 Stacked Pattern Diversity............................................................................141
5.5 Path Loss Compensated Quasi-Reflector Module................................................142
5.6 Design Guidelines for High Aperture Efficiency Antenna..................................143
5.7 Case Studies: Measurement in a Typical Indoor Environment...........................145
5.8 Conclusion..................................................................................................................146
References..............................................................................................................................146
6. Shared Aperture Antenna with Pattern Diversity for Base Stations.........................149
6.1 Introduction................................................................................................................149
6.2 Shared Aperture Antenna.........................................................................................150
6.3 DPZIM Design and Characterization......................................................................153
6.4 Shared Aperture Antenna with DPZIM..................................................................154
6.5 Design Guidelines for High-Gain Dual-Polarized Antenna Module.................160
6.6 Conclusion..................................................................................................................160
References..............................................................................................................................160
7. Co-Design of 4G LTE and mmWave 5G Antennas for Mobile Terminals................163
7.1 Introduction................................................................................................................163
7.2 Miniaturization Techniques for Antenna Size Reduction....................................163
7.3 Conformal 4G LTE MIMO Antenna Design...........................................................164
7.3.1 CRLH-Based Conformal 4G LTE Antenna................................................164
7.3.2 Compact CRLH-Based Conformal 4G LTE MIMO Antenna..................168
7.4 Conformal mmWave 5G MIMO Antenna..............................................................172
7.5 Corner Bent Integrated Design of 4G LTE and mmWave 5G Antennas............176
7.5.1 4G LTE Antenna Design...............................................................................176
7.5.2 mmWave 5G Antenna Design.....................................................................177
7.5.3 Co-Designed Corner Bent 4G LTE and mmWave 5G MIMO Antennas....181
7.6 Case Study: Co-Design of 4G and 5G Antennas in a Smartphone.....................184
7.7 Conclusion..................................................................................................................185
References..............................................................................................................................186
8. Corner Bent Phased Array for 5G Mobile Terminals...................................................189
8.1 Introduction................................................................................................................189
8.2 Phased Array Designs for mmWave Frequencies.................................................190
8.3 Need for Corner Bent Phased Array.......................................................................192
8.4 Corner Bent Phased Array on Polycarbonate........................................................194
8.5 Design Guidelines for a Phased Array at Ka Band...............................................200
8.6 Conclusion..................................................................................................................200
References..............................................................................................................................201
9. Fabrication and Measurement Challenges at mmWaves.............................................203
9.1 Introduction................................................................................................................203
9.2 Fabrication Process and Associated Tolerances.....................................................203
9.3 S-parameter Measurements......................................................................................206
9.4 Pattern Measurements and Sources of Error.........................................................207
9.5 Gain Measurements...................................................................................................209
9.6 Conclusion.................................................................................................................. 211
References.............................................................................................................................. 211
10. Research Avenues in Antenna Designs for 5G and beyond.......................................213
10.1 Introduction................................................................................................................213
10.2 PCB-Based Antenna Designs for 5G Cellular Devices.........................................213
10.3 Application of Additive Manufacturing for Antennas.........................................215
10.3.1 A Dual Band mmWave Antenna on 3D Printed Substrate.....................216
10.4 On-Chip Antennas for CMOS Circuitry.................................................................219
10.4.1 A Wideband CPS-Fed Dipole on Silicon....................................................220
10.5 Optically Transparent Antennas..............................................................................225
10.6 Conclusion..................................................................................................................226
References..............................................................................................................................226
Appendices...................................................................................................................................229
Appendix A: Hints for Simulations in Ansys HFSS........................................................229
A.1 Modelling................................................................................................229
Appendix B: Measurement Issues with End-Launch Connector...................................233
Appendix C: Material Parameters Extraction Using S-parameters..............................234
Appendix D: Useful MATLAB Codes................................................................................235
References..............................................................................................................................237
Index..............................................................................................................................................239