theory of dipoles, array factors, and multi-element antennas with physics-based propagation for ...

190 Pages·2014·9.62 MB·English

THEORY OF DIPOLES, ARRAY FACTORS,
AND MULTI-ELEMENT ANTENNAS
WITH PHYSICS-BASED PROPAGATION
FOR MOBILE COMMUNICATIONS
by
Maryam Dehghani Estarki
M.Sc., University of Tehran, 2004
B.Sc., University of Tehran, 2000
a Thesis submitted in partial fulfillment of
the requirements for the degree of
Doctor of Philosophy
in the
School of Engineering Science
Faculty of Applied Sciences
⃝c Maryam Dehghani Estarki 2014
SIMON FRASER UNIVERSITY
Summer 2014
All rights reserved. However, in accordance with the Copyright Act of Canada, this work
may be reproduced, without authorization, under the conditions for Fair
Dealing. Therefore, limited reproduction of this work for the purposes of private
study, research, criticism, review and news reporting is likely to be in accordance
with the law, particularly if cited appropriately.
APPROVAL
Name: Maryam Dehghani Estarki
Degree: Doctor of Philosophy
Title of Thesis: Theory of Dipoles, Array Factors, and Multi-Element Anten-
nas with Physics-Based Propagation for Mobile Communica-
tions
Examining Committee: Dr. Jie Liang, Associate Professor, Ph.D., P.Eng.
Chair
Dr. Rodney G. Vaughan
Senior Supervisor, Professor, Ph.D., P.Eng.
Dr. Shawn Stapleton
Supervisor, Professor, Ph.D., P.Eng.
Dr. Daniel Janse van Rensburg, Nearfield Systems,
Adjunct Professor, Supervisor, Ph.D., P.Eng.
Dr. Behrouz Pourseyed, Sierra Wireless Inc., RF Di-
rector, Supervisor, Ph.D.
Dr. Daniel C. Lee, Simon Fraser University
Internal Examiner, Professor, Ph.D., P.Eng.
Dr.RobertPaknys,ConcordiaUniversity,ECEDept.
External Examiner, Professor, Ph.D., P.Eng.
Date Defended/Approved: April 29, 2014
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Partial Copyright Licence

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Abstract
Bandwidth, volume and energy are the basic resources for communications, and current
signal processing techniques use these in many different ways. The bandwidth is limited by
the antenna size, and maximizing the bandwidth of the elements and the design of multi-
element antennas (MEAs) require new research. This two-part thesis addresses antenna-
theoretic bandwidth and MEA evaluation.
The limiting bandwidth of the most fundamental antenna element - the dipole - remains
elusive despite its long research history. This motivates Part I, in which the bandwidth of
the electric dipole is developed from theoretical and numerical methods, and recent mea-
surements. The resulting antenna-theoretic bandwidth of the dipole with a feed gap offers
new benchmark results for compact elements. The lossless, thin dipole with finite gap has a
much wider bandwidth than was previously known, and the non-radiating feed is identified
as the challenge to realize the available bandwidth.
Using multiple-input multiple-output (MIMO) and other diversity techniques with large
dimensions (many elements) is the key technology for high spectral efficiency. But large-
dimension MIMO is not yet used commercially, and the design methodology and evaluation
of MEAs is undeveloped. There is no standard for evaluating MEAs used for MIMO com-
munications, and currently, the physical evaluation of a MIMO terminal comprises coarse
throughput tests in an idealized environment. The real-world performance of the terminal,
and especially the antenna performance, remains unclear from such tests. This motivates
Part II, which explores MEA evaluation using physical antenna parameters together with
site-specific, ray-traced models for the spatial channel. Ray-tracing calculation is well es-
tablished, but its application with MEAs is in its infancy. Using third-party ray-tracing
files, an approach for evaluating MEAs for urban channels is presented. The advantage
is that it maintains the full control of being computer-driven, thereby avoiding expensive,
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hard-to-repeat physical measurements, while incorporating the ground-truth of empirical
antenna parameters.
keywords: wiredipole;Qbounds;mmwaveantennas;array;ray-tracing;MIMO/diversity
v
To my parents, Mehrzad and Mahmood,
for all the beauty and love they always (cid:12)ll my life with,
and to my brother, Maziar,
for his unconditional friendship and support.
Maral
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\It took me so long to (cid:12)gure out where he was coming from. The Little Prince, who was
asking me too many questions, did not seem to hear at all the ones I was asking him. It
was from the words uttered by chance that, little by little, everything was revealed to me."
| The Little Prince, Antoine de Saint-Exupry, 1900-1944
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Acknowledgments
I always knew writing this part of the thesis would be the hardest. Since I started this
journey, many amazing people have been accompanying me, without their love, support,
care, patience and endurance, I have never been able to survive a single day. I would like
to acknowledge some of these many people.
There is no way to thank my senior supervisor at the School of Engineering Science,
SFU, Dr. Rodney G. Vaughan. He invited me to work in his research group when I was
about to leave this school. He changed my points of views about science and research. This
thesis and all my publications were accomplished by his constant supervision and support.
Though, what I learnt from Rodney is much more than my research and my papers. He
assisted me improving my writing style and my communications skills. During the stages
thatIwasphysicallyandemotionallyweak,Rodneyandhisencouragingwordsmademefeel
stronger, stand up and proceed. Whenever I was demotivated and frustrated of research, he
was there offering a new approach. Many of his brilliant ideas have become the foundation
of the present dissertation. In response to my faults and mistakes, he was patient and
forgiving. Being a member of his research team was one of the best things ever happened
to me. He helped me gain back my interest in research. At last, I have to mention that he
financially supported me from the very first day I joined his team till the day I defended
my thesis and that made the way much smoother for me to pass.
I wish to express my sincere gratitude and appreciation to my former supervisors,
Dr. Dong In Kim and Dr. Paul Ho. Dr. Kim gave me the admission to join SFU and
start my PhD in Vancouver. He supervised me during the first two semesters of my study
at SFU. He is one of the most knowledgeable people in the ultra wideband research and
a great mentor in this field. I also want to thank Dr. Paul Ho, my second (temporary)
supervisor, for all I learnt from him during the single semester I worked with him. He is
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an excellent teacher and I very much profited from his guidance and knowledge in digital
communications.
I am so grateful to my supervisor Dr. Shawn Stapleton who has always been positive
about my work and research since September 2007 that I started working with him as a
teaching assistant. It was a great pleasure to work for him. Since then, he has been one of
my best friends at SFU from whom I always get advice.
I want to thank my supervisor, Dr. Daniel Janse van Rensburg from Nearfield Systems
Inc. Daniel traveled from the other side of the country, made it to my defence session and
provided me with thoughtful comments and questions. His comments were so detailed and
he had captured some points that I had not seen before.
I wish to express my appreciation to Dr. Behrouz Pourseyed from Sierra Wireless Inc.
Hebecameamemberofmysupervisorycommitteedespitehisbusyscheduleandsupervised
my thesis progress insightfully. Behrouz’s practical comments prompted me to consider the
problemfromanotherangle. Hisbrilliantquestionsduringthedefencesessiondelightedme.
It is my honor to thank my external examiner, Dr. Robert Paknys who traveled from
Montreal for my defence. He provided me with great comments during the defence session
and left me with his precious constructive notes after the defence.
I want to express my gratitude to Dr. Daniel C. Lee, my internal examiner, for his
insightful questions and for his nice and supportive contribution. I was always inspired by
his passion for learning and teaching. He is always around and always eager for new ideas.
I am thankful to the defence chair, Dr. Jie Liang for his valuable contribution. He is an
amazing graduate chair who is always there to assist you.
I warmly acknowledge Dr. Yvo de Jong from Communications Research Centre Canada
(CRC), and Dr. Thomas Ku¨rner and Mr. J¨org Nuckelt from Braunschweig Technische Uni-
versit¨at Germany for generating and supplying a sample file of simulated channels. They
patiently answered my questions and kindly helped me all along the way.
I want to thank all the faculty and staff of the School of Engineering Science for their
support during my graduate study at SFU. Especially, I want to thank Ms. Raj Pabla,
Ms. Lindsay Ward, Ms. Roya Ghorab, Mr. Chao C. Cheng, Mr. Gary Houghton, Mr. Gary
Shum and Mr. Bryan Sales.
I am so grateful to my amazing mentors at the Engineering Science Co-operative Ed-
ucation Program at SFU for their support and encouragement, especially to Ms. Harriet
Chicoine for her trust and encouragement. During the two semesters with Co-op office, I
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enjoyedworkingwithMs.ShannonDanson,Ms.IsabellaSilvestreandMs.HeatherKeeping.
I express my appreciation to Mr. Steve Whitmore for all I learnt from his writing course
and all the joy I had while I was working as a TA for him.
I thank Health and Counselling Services at SFU, especially Dr. Dianne Vosloo and
Ms. Enzula Tavormina for the all the efficient sessions I had with them.
Iamindebtedtomylabcolleaguesfortheirfriendship,encouragementandadviceduring
these years. Jane Xing Yun helped me a lot in using simulation packages. She kindly pro-
vided me with the patterns of the antennas she had simulated and measured. My colleague,
Xu Han, also, assisted me a lot in numerical methods. I express my special thanks to the
past and current members of the Sierra Wireless Communications Laboratory, Nima Ma-
hanfar, Sara Bavarian, Shirin Karimifar, Ted Liu, Jinyun Ren, Muhammad Naeem, Alireza
Banani, Mehdi Seyfi, Piraj Fozoonmayeh, Omar Altrad, Jaspreet Oberoi, Moein Shayegan
Nia, Saeed Asharfinia, Milad Amir Toutounchian, Ali Zarei, Maryam Razmhosseini, Ying
Chen, Abhijit Bhattacharya and Hanieh Khalilian.
I also want to thank my amazing friends form SFU who were always there for me,
Arina Aboonabi, Lila Torabi, Parastoo Dehkordi, Mahsa Najibi, Farnaz Gharibian, Leila
Kalantari, Reza Entezari, Maryam Soleimani, Esmaeil Tafazzoli, Neda Changizi, Vahid
Kazempour and Kaveh Kianfar. I want to thank my friends Anooshe Bazzazan, Alireza
Saremi, Nooshin Karimifar and Azadeh Hajihosseini for their support and encouragement.
I would like to thank my friends Mona Jafarnejad, Vafa Sarmast, Neda Ehtiati and
Sahar Ayazian for being so close to me although they are so far away from Vancouver and
for being so amazing to me all the time.
I am grateful to my beloved friend, Armita Kaboli. There is no way to thank her (and
her family) for the priceless friendship. She always gave me courage and energy. She was
listening patiently to me and was offering me incredible solutions.
I wish to thank my aunts and uncles and my beloved cousins who were so supportive
from different parts of the world. I want to thank my Grandma, Irandokht Aminian, who
has been the best Grandma ever. I will always remain thankful and grateful to them.
I have no word to thank my dear friend Hassan Goldani Moghaddam who never stopped
supporting, encouraging and helping me. He was unbelievably patient with me throughout
my research and was always encouraging and understanding during the toughest times. He
was by my side all over my study at SFU. While I was so overwhelmed by my thesis, every
night he was coming to the lab with a big smile and a bar of chocolate asking me how my
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