ACTIVE ANTENNAS FOR RF SYSTEMS
by
MADHUR DEO UPADHAYAY
CENTRE FOR APPLIED RESEARCH IN ELECTRONICS
Submitted
in fulfillment of the requirements of the degree of Doctor Of Philosophy
to the
INDIAN INSTITUTE OF TECHNOLOGY DELHI
JULY 2013
CERTIFICATE
This is to certify that the work reported in this thesis entitled “Active Antennas for RF System”, being submitted by Mr. Madhur Deo Upadhayay for the award of the degree of Doctor of Philosophy (Ph. D.) to the Indian Institute of Technology Delhi, New Delhi, India, is a record of original bonafide research work carried out by him under our guidance and supervision. The results contained in this thesis have not been submitted in part or full, to any other university or institute for the award of any degree or diploma.
We certify that he has pursued the prescribed course of research.
Dr. ANANJAN BASU Dr. MAHESH P. ABEGAONKAR
Professor Assistant Professor
Centre for Applied Research Centre for Applied Research
in Electronics (C A R E) in Electronics (C A R E)
Indian Institute of Technology Delhi, Indian Institute of Technology Delhi, New Delhi -110016, India. New Delhi -110016, India.
Date:
New Delhi
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ACKNOWLEDGEMENTS
A doctoral thesis, though driven by the candidate, is built on a foundation of guidance and support of many individuals. I would like to thank all people who have helped and inspired me during my doctoral study.
I would like to record my sincere gratitude to Prof. Ananjan Basu for his vast experience and gentle guidance which has steered me through each stage of my research. I also thank him for providing constant encouragement and support.
I gratefully acknowledge Dr. Mahesh P. Abegaonkar for his valuable advice, and supervision. His constant encouragement and support have been crucial in the completion of this thesis. His involvement and his originality have triggered and nourished my intellectual maturity which will be beneficial for me throughout my life.
I was privileged to have interacted with Prof. S. K. Koul by attending his classes and having him as my course advisor and expert of my research area. His guardianship and sincerity are beyond the scope of acknowledgement.
I express my sincere thanks to Prof. Devi Chadda, Professor, EE Department, IIT Delhi for providing me equipment from her laboratory.
Collective and individual acknowledgments are also owed to my colleagues at CARE whose presence somehow perpetually refreshed, helpful, and memorable. I am thankful to Dr.
(Ms.) Preeti Sharma, Dr. Mithilesh Kumar, Dr. Manoj Singh Parihar, and Dr. Sandeep Chaturvedi for their valuable suggestions. Thanks to Lalithendra Kurra, Ritabrata Bhattacharya, Sukomal Dey, Sanjeeb Kumar, Srujana Kagita, Tweldebrahan, Ankita Katyal, and Saurabh Pegwal for their company. My thanks to project staff Mr. Ravi Dutt Gupta and Ms. Pooja Prakash. I am thankful to Dr. V. J. Thomas for his companionship.
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I would like to thank all CARE faculty and staff members for helping me complete my research successfully. I am thankful to Mr. S. P. Chakraborty for providing technical support for operating and maintaining equipments. Support from Mr. Ashok Pramanik is duly acknowledged.
I would like to express my everlasting gratitude to my uncle Shri S. D. Upadhayay and my father Dr. G. D. Upadhayay for encouraging me to pursue a doctoral degree. I am eternally indebted to my sister Neha, brother Abhishek and sister- in- law Alpi who remained with me throughout the past few years; they took the load off my shoulders and made my thoughts positive. Finally, at a very personal level, the patience, cooperation and constant encourangement of my wife Neelu and children Daksha and Vivaan during my research work, merit a warm acknowledgement.
Above all, I thank almighty God, for giving me the intellect to understand the complexity of numbers, and giving me strength to complete this research.
Madhur Deo Upadhayay
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ABSTRACT
This thesis deals with the design and development of frequency reconfigurable active antenna, active antenna using floating-base BJT and study on injection locking in active antenna.
Various passive antenna structures have been developed for active antenna application. Two and three port annular slot antennas, three-port rectangular slot antenna were designed for active antenna application. These antennas were designed using MIC technology. This antenna can be used for short range communication in Industrial Scientific and Medical (ISM) and bands.
A frequency switchable active antenna has been developed using three port rectangular slot antenna (RSA). This circuit consists of RF BJT as an amplifying device and two P-I-N diodes in SPDT configuration. The switching time of the proposed active antenna has been studied. This active antenna can be used for WLAN. This idea can also be used to develop high end active antenna for defence application which would be immune to interference and jamming.
A feedback-oscillator type active antenna using RF BJT with floating base terminal has been developed for the first time. At d.c. the base terminal of BJT is kept floating in this active antenna.Other than simplifying bias connections, which is important for large arrays and power combining, this has potential for future optical sensing and control circuitry, since the floating base is light-sensitive. Injection locking has been verified also for this active antenna.
The injection locking of active antenna has been studied in frequency domain and time domain.
Time domain study of injection locking has been done for the first time in active integrated antenna. The locking delay plays an important role in communication systems. The factors affecting locking delay have been studied.
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CONTENTS
I Certificate i
II Acknowledgements ii
III Abstract iv
IV Contents v
V List of Figures viii
VI List of Tables xiii
VII List of Abbreviations xiv
CHAPTER – 1
Review & Scope of the Thesis
1.1 Introduction 1
1.2 Active Antenna 2
1.3 Injection Locking 5
1.4 Applications 7
1.4.1 Automotive applications 7
1.4.2 Sensor applications 8
1.4.3 Communication or tag applications 8
1.5 Problem Statement 10
1.6 Scope and Organisation of the Thesis 10
CHAPTER – 2
Passive Antennas Suitable For Use in Reconfigurable Active Antennas
2.1 Introduction 12
2.2 Two Port Annular Slot Antenna 13
2.2.1 Dual Port Annular Slot Design 14
2.2.2 Parametric Analysis 15
2.2.3 Results and Discussion 19
2.3 Three Port Annular Slot Antenna 23
2.3.1 Design of Three Port ASA 23
2.3.2 Parametric Analysis 24
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2.3.3 Results and Discussion 25
2.4 Design, Simulation, Fabrication And Characterization of Two
Port Annular Slot Circular Polarized Antenna 31
2.5 Three Port Rectangular Slot Antenna 35
2.5.1 Design of Three Port RSA 35
2.5.2 Parametric Analysis 36
2.5.3 Result and Discussion 41
2.6 Conclusions 43
CHAPTER – 3
Frequency Reconfigurable Active Antenna
3.1 Introduction 44
3.2 Frequency Reconfigurable Active Antenna Design 44
3.3 Fabrication and Measurement 48
3.4 Conclusions 58
CHAPTER – 4
Floating Base Active Antenna
4.1 Novel Floating Base Active Antenna 59
4.2 Design and Measurement 59
4.3 Injection Locking in Novel Active Antenna 63 4.4 Model of Active Antenna and Transient Analysis 69
4.5 Conclusions 69
CHAPTER – 5 Injection Locking
5.1 Introduction 71
5.2 Injection Locking in Active Antenna 72
5.3 Locking Delay 82
5.4 Conclusions 84
vii CHAPTER – 6
Conclusions and Scope For Future Research
6.1 Summary of Thesis 85
6.2 Scope for Future Research 86
References 87
Appendix-I 95
Appendix-II 124
List of Publications 130
Brief Bio-Data of the Author 131
