Manipulating Antenna Radiation with Angle Holography by Michael Chen A thesis submitted in

179 Pages·2015·14.56 MB·English

Manipulating Antenna Radiation with Angle Holography
by
Michael Chen
A thesis submitted in conformity with the requirements
for the degree of Master of Applied Science
The Edward S. Rogers Sr. Department of Electrical and
Computer Engineering
University of Toronto
(cid:13)c Copyright 2015 by Michael Chen
Abstract
Manipulating Antenna Radiation with Angle Holography
Michael Chen
Master of Applied Science
Graduate Department of Electrical and Computer Engineering
University of Toronto
2015
Holography discovered by Dennis Gabor in 1948 is traditionally used in optics to pro-
duce 3D holographic photos. Antenna engineers inspired by this idea have since brought
forth holographic antennas to microwave frequencies. However these antenna systems
are typically difficult to design and fabricate. In this work a new holographic antenna
design is investigated. By analysing interference patterns we devised a method of using
tilted radiating elements to represent holographic patterns. In contrast to traditional
holographic antennas, our approach dubbed angle holography uses the radiators as both
the holographic sampling and excitation source. By using rotations, the antennas are
easy to design and fabricate. Arrays using single dipole, cross dipoles, single slot coupled
patch, and cross slots coupled patch antennas were implemented. Simulations of conical
beam, single beam steering, and beam focusing are demonstrated with single and dual
polarization control. Lastly a fabricated prototype is tested confirming the simulated
results.
ii
To my loving parents
and my dearest friends
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Acknowledgements
First and foremost I would like to express my highest respect and gratitude to my
supervisor Professor George Eleftheriades for giving me this wonderful opportunity to be
a part of this work. It has been a privilege to have a supervisor as encouraging, patient,
and supportive as Professor Eleftheriades. It goes without saying that this thesis could
not have been possible without his help and guidance. It has truly been an honour to
have worked with him.
I would also like to thank Professor Hum, Professor Triverio, and Professor Tate for
being members of my defense committee. I appreciate all the feedback and questions
regarding the thesis. As well I am very thankful of them for taking their time to be a
part of my thesis defense.
Iwouldalsoliketoextendmygratitudetomyfellowcolleaguesintheelectromagnetics
group. I am very proud to be a member of our team and to work along side such a
dedicated and intellectual group of individuals. It has been wonderful getting to know
all of you through the years, and I could not have asked for better mentors during my
time here. Although I am glad to have defended my thesis and completed my Master’s
research, perhaps my greatest gain through this experience has been befriending all of
you. It has been and always will be a privilege to have known you all.
Most importantly I want to thank my loving parents. This thesis, my education, and
everything in my life would not have been the same without them. It is through the
sacrifices and the support of my mom and dad that I have been able to achieve this. I
am very lucky to have been blessed with a great family and my only hope is that I have
made them proud. I will always be grateful to them and I will always love them.
Of course I could not forget to thank all my dearest friends. Some of whom I have
known since my first days in Toronto, others I have gotten to know along the way.
Although I do not always express it, I have always been very thankful for their support
in my academic goals. A special thanks goes out to my best friend Jay whose been with
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me since day one. I think Jay put in as much work getting me through the years alive
as I have working on this thesis. Without his support I would not have been able to get
to where I am now. Thanks buddy, for the last few years, and to many more to come.
Last but certainly not least, I want to thank a very dear friend of mine who unfortu-
nately will never have the opportunity to read this. I know I speak for both Jay and I
when I say that we miss her very much. Although Megan did not directly influence this
thesis, herimpactonmehelpedinshapingmeintowhoIamtoday. Ithasbeenablessing
and an honour to have been her friend. I have always regretted not properly telling her
how much I appreciated knowing her. So I am taking the time now to acknowledge my
sincere gratitude towards her. I have never been good at writing conclusions so I shall
simply leave with my favorite quote from her. In the words of my dear friend Megan,
”You can sleep when you are dead”.
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Contents
1 Introduction 1
1.1 Brief History of Holography . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Motivation of Holographic Systems . . . . . . . . . . . . . . . . . . . . . 5
1.3 Project Proposal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.4 Thesis Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2 Holography 9
2.1 Principle of Holography . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.2 Beam Steering Example . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2.3 Beam Focusing Example . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
3 Angle Holography Array 27
3.1 Angle Holography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
3.2 Beam Steering Array . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
3.3 Conjugate Beam . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
3.4 Beam Focusing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
4 Polarization Control Array 56
4.1 Cross-Polarization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
4.2 Cross Dipole Cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
4.3 Minimizing Cross Polarization . . . . . . . . . . . . . . . . . . . . . . . . 66
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4.4 Additional Polarization Control . . . . . . . . . . . . . . . . . . . . . . . 70
5 Microstrip Realization 75
5.1 Slotted Patch Antennas . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
5.2 Slot Patch Array Feeding Network . . . . . . . . . . . . . . . . . . . . . . 80
5.3 Single and Cross Slotted Patched Array . . . . . . . . . . . . . . . . . . . 84
6 Microstrip Angle Holography Array Design 87
6.1 Overall Design Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . 87
6.2 Interference Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
6.3 Single-Slot Aperture-Coupled Patch . . . . . . . . . . . . . . . . . . . . . 96
6.4 Single-Slot Aperture-Coupled Patch Array without Feed Network . . . . 100
6.5 Single-Slot Aperture-Coupled Patch Array with Feed Network . . . . . . 104
6.6 Cross-Slot Aperture-Coupled Patch . . . . . . . . . . . . . . . . . . . . . 109
6.7 Cross-Slot Aperture-Coupled Patch Array without Feed Network . . . . . 115
6.8 Cross-Slot Aperture-Coupled Patch Array with Feed Network . . . . . . 118
6.9 Optimization of Prototype Antenna . . . . . . . . . . . . . . . . . . . . . 121
7 Experimental Results 130
7.1 Experimental Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
7.2 Experimental Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
8 Future Possibilities 148
8.1 Future Opportunities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
8.2 Amplitude Beam Steering . . . . . . . . . . . . . . . . . . . . . . . . . . 148
8.3 Electric and Magnetic Holography . . . . . . . . . . . . . . . . . . . . . . 151
9 Conclusion 152
Appendix A Far-Field Dipole Angle Holography Array 155
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Bibliography 160
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List of Tables
6.1 Single slot rotations for beam steering angles of 30◦, 45◦, and 60◦ with
normally incident reference wave. . . . . . . . . . . . . . . . . . . . . . . 90
6.2 Single slot rotations for beam steering angles of 30◦, 45◦, and 60◦ with
oblique incident reference wave. . . . . . . . . . . . . . . . . . . . . . . . 92
6.3 Cross slot rotations for beam steering angles of 30◦, 45◦, and 60◦ with
normal incident reference wave. . . . . . . . . . . . . . . . . . . . . . . . 93
6.4 Cross slot rotations for beam steering angles of 30◦, 45◦, and 60◦ with
oblique incident reference wave. . . . . . . . . . . . . . . . . . . . . . . . 95
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List of Figures
1.1 Holographic image of a leopard [4]. . . . . . . . . . . . . . . . . . . . . . 2
1.2 Examples of equivalent holographic films (a) linear metallic film [7], (b)
curvi-linear metallic film [8], and (c) impedance holographic film [9]. . . . 3
2.1 General holographic process (a) obtaining and recording the interference
pattern (b) wave reconstruction via exciting the hologram. . . . . . . . . 10
2.2 Hologramcreationprocessofaninterferencepatternusingareferencewave
with an object wave and simplified photographic film. . . . . . . . . . . . 12
2.3 Exciting the hologram with a secondary wave resulting in four wave com-
ponents. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
2.4 Exciting a hologram with the initial reference wave to obtain object wave
reconstruction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2.5 Expansion of the interference function with generalized reference and ob-
ject waves to obtain the cosine varying intensity expression. . . . . . . . 17
2.6 Holography beam steering with a normal incident reference plane-wave
and an oblique incident object plane-wave with interference plane lying
along the z axis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2.7 Holography beam focusing with a normal incident reference plane-wave
and a spherical object wave with interference plane lying along the x =
−f axis denoting the focal length. . . . . . . . . . . . . . . . . . . . . . . 23
x