Foreword ....................................................... xi
Preface ...................................................... xiii
CHAPTER 1
Electrically Small Multiband Antennas ........................... 1
1.1 Introduction ................................................ 1
1.2 The Definition of Electrically Small ........................ 2
1.3 Fundamental Antenna Properties Definitions .................. 3
1.3.1 Impedance, Efficiency, VSWR, and Gain ................. 3
1.3.2 Bandwidth and Quality Factor (Q) ...................... 6
1.4 Fundamental Limits of Small Antennas ....................... 10
1.5 Special Considerations for Integrated Multiband Antennas ... 12
1.6 Fundamental Approaches to Small Integrated Antenna
Design ..................................................... 16
1.6.1 The Monopole Antenna ................................. 16
1.6.2 The Inverted-L Antenna ............................... 17
1.6.3 The Inverted-F and Planar Inverted-F Antennas ........ 18
1.7 Finite Ground Plane Effects on Small Antenna Performance ... 22
References ................................................. 30
CHAPTER 2
Multiband Multisystem Antennas in Handsets ..................... 33
2.1 Introduction ............................................... 33
2.1.1 Frequencies and Systems .............................. 33
2.1.2 Typical Specifications ............................... 36
2.2 Multiband Techniques ....................................... 36
2.2.1 Radiating and Balanced Mode Theory ................... 37
2.2.2 Analysis of PIFA Slots ............................... 41
2.2.3 Analysis of PIFA Shorting Pins ....................... 43
2.3 Multisystem Techniques ..................................... 45
References ................................................. 52
CHAPTER 3
Multiband Planar Wire Antennas ................................. 53
3.1 Introduction ............................................... 53
3.2 Multiband Planar Monopole Antennas ......................... 59
3.2.1 Microstrip-Fed Dual-Band Monopole Antenna ............ 60
3.2.2 CPW-Fed Dual-Band Monopole Antenna ................... 60
3.2.3 Meandered CPW-Fed Multiband Monopole Antenna ......... 62
3.3 Inverted-L Multiband Antennas .............................. 63
3.3.1 Modified Double Inverted-L Antenna for Multiband
Operation ............................................ 63
3.3.2 Inverted-L Antenna with a Parasitic Element for
Dual-Band Operation .................................. 67
3.4 Inverted-F Antennas for Dual-Band Operation ................ 68
3.4.1 Spiraled Inverted-F Antenna for Dual-Band
Operation ............................................ 68
3.4.2 Coupling Dual-Band Inverted-F Antenna ................ 71
3.4.3 Inverted-FL Antennas with a Parasitic Inverted-L
Element for Bandwidth Enhancement .................... 74
3.5 T-Shaped Antennas for Multiband Operation .................. 75
3.5.1 Single T-Shaped Antenna for Multiband Operation ...... 75
3.5.2 Double T-Shaped Antenna for Dual-Band Operation ...... 77
3.5.3 T-Shaped Antenna with a Parasitic Inverted-L
Element for Bandwidth Improvement .................... 78
3.6 Meandered Multiband Antennas ............................... 79
3.6.1 A Nonuniform Meandered Antenna with a Forked Ground
Plane for Multiband Operation ........................ 80
3.6.2 A Compact Multiband Meandered Planar Antenna ......... 82
3.7 M-Shaped Planar Monopole for Multiband Operation ........... 83
3.8 Two-Strip Planar Antennas for Broadband and Multiband
Operation .................................................. 85
3.8.1 Broadband Two-Strip Antenna .......................... 85
3.8.2 Broadband/Dual-Frequency Two-Strip Antenna ........... 89
3.9 Conclusions ................................................ 92
References ................................................. 93
CHAPTER 4
Printed Multiband Fractal Antennas ............................. 95
4.1 Introduction ............................................... 95
4.1.1 Brief Background on Fractal Geometry ................. 95
4.1.2 Fractals in Nature ................................... 97
4.1.3 Prefractals: Truncating a Fractal to Useable
Complexity ........................................... 99
4.1.4 How Fractals Can Be Used as Antennas and Why
Fractals Are Space-Filling Geometries ............... 100
4.1.5 The Fractal Dimensions of Box Counting, Hausdorff,
and Similarity ...................................... 101
4.2 Fractals Defined by Transformations - Self-Similar and
Self-Affine Sets .......................................... 109
4.2.1 Iterated Function Schemes: The Language of
Fractals ............................................ 109
4.2.2 Self-Affine Sets .................................... 112
4.3 Deterministic Fractals as Antennas ........................ 113
4.3.1 Fractals as Wire Antenna Elements ................... 114
4.3.2 Fractal Patch Elements .............................. 125
4.3.3 Circularly Polarized Microstrip Fractal Antennas .... 138
4.4 Fractal Arrays and Fractal Volume Antennas ................ 141
4.4.1 Multiband Fractal Arrays ............................ 143
4.5 Conclusions ............................................... 147
References ................................................ 147
CHAPTER 5
Miniaturized Integrated Multiband Antennas .................... 151
5.1 Design Considerations for Integrated Multiband Handset
Antennas .................................................. 151
5.1.1 Hearing Aid Compatible Handsets ..................... 152
5.2 Effect of the Terminal on the Antenna Behavior ............ 153
5.2.1 Effect of the Size of the Chassis ................... 153
5.2.2 Effect of the Handset Components .................... 157
5.3 Modal Analysis ............................................ 164
5.3.1 The Theory of Characteristic Modes .................. 165
5.3.2 Practical Applications .............................. 172
Acknowledgments ..................................... 182
References .......................................... 229
CHAPTER 6
Multiband Handset Antennas for MIMO Systems ................... 187
6.1 Introduction .............................................. 187
6.2 Design Considerations for MIMO Systems .................... 188
6.2.1 Diversity Techniques ................................ 190
6.2.2 Volume Constraints: The MIMO Cube ................... 198
6.3 MIMO Techniques in a Handset .............................. 198
6.3.1 Effect of Antenna Efficiency ........................ 199
6.3.2 Effect of User Presence ............................. 212
6.3.3 Effect of Antenna Correlation ....................... 219
6.4 Combined Diversity Techniques for Optimum Handset MIMO
Performance ............................................... 223
CHAPTER 7
Communication Performance of Mobile Devices ................... 235
7.1 Introduction .............................................. 235
7.2 Antenna Efficiency ........................................ 241
7.2.1 Radiation Efficiency ................................ 242
7.2.2 How to Obtain the Antenna Efficiency ................ 242
7.2.3 Conductive Cable Problem ............................ 243
7.2.4 Total Radiated Power and Total Isotropic
Sensitivity ......................................... 246
7.3 User Influence ............................................ 247
7.3.1 Experimental Setup .................................. 248
7.3.2 Repeatability Test .................................. 251
7.3.3 Variation Due to Different Users .................... 252
7.3.4 Influence of Hand Position .......................... 254
7.3.5 Summary ............................................. 257
7.4 Mean Effective Gain ....................................... 258
7.4.1 Power Distribution Models ........................... 260
7.4.2 Single Antenna ...................................... 266
7.4.3 Multiple Antennas ................................... 274
7.5 Standard Measurement Setup Using Phantoms ................. 281
7.5.1 Setup for Measurements of Mobile Handset Radiation
Patterns ............................................ 282
7.5.2 Measurement Uncertainty ............................. 284
7.5.3 Errors Due to Insufficient Sampling Density of
Radiation Pattern ................................... 284
7.5.4 Investigation of Phantom Type Influence on
Performance ......................................... 285
7.5.5 Uncertainty Due to Incorrect Handset Positioning
on Phantom .......................................... 288
References .......................................... 292
List of Acronyms .............................................. 295
About the Editor .............................................. 299
About the Authors ............................................. 301
Index ......................................................... 307
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