cover

Contents

Cover

Title Page

Copyright

Preface

References

List of Contributors

Acknowledgments

Chapter 1: Numerical Analysis Techniques

1.1 Introduction

1.2 Standard (Yee's) FDTD Method

1.3 Numerical Dispersion of FDTD and Hybrid Schemes

1.4 Stability of Algorithms

1.5 Absorbing Boundary Conditions

1.6 LOD-FDTD Algorithm

1.7 Robustness of Printed Patch Antennas

1.8 Thin Dielectric Approximation

1.9 Modeling of PEC and PMC for Irregular Geometries

References

Chapter 2: Computer Aided Design of Microstrip Antennas

2.1 Introduction

2.2 Microstrip Patch as Cavity Resonator

2.3 Resonant Frequency of Circular Microstrip Patch (CMP)

2.4 Resonant Frequency of Rectangular Microstrip Patch (RMP) with Variable Air Gap

2.5 Resonant Frequency of Equilateral Triangular Microstrip Patch (ETMP) with Variable Air Gap

2.6 Input Impedance of a Microstrip Patch

2.7 Feed Reactance of a Probe-Fed Microstrip Patch

2.8 Radiation Characteristics

2.9 Radiation Efficiency

2.10 Bandwidth

2.11 Conclusion

References

Chapter 3: Generalized Scattering Matrix Approach for Multilayer Patch Arrays

3.1 Introduction

3.2 Outline of the GSM Approach

3.3 Mutual Coupling Formulation

3.4 Finite Array: Active Impedance and Radiation Patterns

3.5 Numerical Example

3.6 Conclusion

References

Chapter 4: Optimization Techniques for Planar Antennas

4.1 Introduction

4.2 Basic Optimization Concepts

4.3 Real Coded Genetic Algorithm (RCGA)

4.4 Neurospectral Design of Rectangular Patch Antenna

4.5 Inset-fed Patch Antenna Design Using Particle Swarm Optimization

4.6 Conclusion

References

Chapter 5: Microstrip Reflectarray Antennas

5.1 Introduction

5.2 General Review of Reflectarrays: Mathematical Formulation and General Trends

5.3 Comparison of Reflectarray and Conventional Parabolic Reflector

5.4 Cell Elements and Specific Applications: A General Survey

5.5 Wideband Techniques for Reflectarrays

5.6 Development of Novel Loop-Based Cell Elements

5.7 Conclusion

References

Chapter 6: Reconfigurable Microstrip Antennas

6.1 Introduction

6.2 Substrate Modification for Reconfigurability

6.3 Conductor Modification for Reconfigurability

6.4 Enabling Reconfigurability: Considerations for Reconfiguration Mechanisms

6.5 Future Trends in Reconfigurable Microstrip Antenna Research and Development

References

Chapter 7: Wearable Antennas for Body Area Networks

7.1 Introduction

7.2 Sources on the Human Body

7.3 Narrowband Antennas

7.4 Fabric Antennas

7.5 Ultra Wideband Antennas

7.6 Multiple Antenna Systems

7.7 Conclusion

References

Chapter 8: Printed Antennas for Wireless Communications

8.1 Introduction

8.2 Broadband Microstrip Patch Antennas

8.3 Patch Antennas for Multiband Wireless Communications

8.4 Enhanced Gain Patch Antennas

8.5 Wideband Compact Patch Antennas

8.6 Microstrip Slot Antennas

8.7 Microstrip Planar Monopole Antenna

References

Chapter 9: UHF Passive RFID Tag Antennas

9.1 Introduction

9.2 Application Requirements

9.3 Approaches

9.4 Fabrication

9.5 Conclusion

Acknowledgments

References

Chapter 10: Printed UWB Antennas

10.1 Introduction

10.2 “Swan” Antenna with Reduced Ground Plane Effect

10.3 Slim UWB Antenna

10.4 Diversity Antenna

10.5 Printed Slot UWB Antenna and Band-Notched Solutions

References

Chapter 11: Metamaterial Antennas and Radiative Systems

11.1 Introduction

11.2 Fundamentals of Metamaterials

11.3 Leaky-Wave Antennas

11.4 Resonant Antennas

11.5 Exotic Radiative Systems

References

Chapter 12: Defected Ground Structure for Microstrip Antennas

12.1 Introduction

12.2 Fundamentals of DGS

12.3 DGS for Controlling Microstrip Antenna Feeds and Front-End Characteristics

12.4 DGS to Control/Improve Radiation Properties of Microstrip Patch Antennas

12.5 DGS for Reduced Mutual Coupling Between Microstrip Array Elements and Associated Improvements

12.6 Conclusion

Appendix: A Brief DGS Chronology

References

Chapter 13: Printed Leaky Wave Antennas

13.1 Introduction

13.2 The Leaky Wave as a Complex Plane Wave

13.3 Radiation Pattern of a Leaky Wave

13.4 Examples of Leaky Mode Supporting Structures

13.5 The Excitation Problem

13.6 Two-Dimensional Leaky Waves

13.7 Further Advances on a Class of Periodic Leaky Wave Antennas

References

Appendix I: Preliminary Ideas: PTFE-Based Microwave Laminates and Making Prototypes

A1.1 PTFE Laminates

A1.2 Making Prototype Boards

A1.3 Making Simple Printed Antennas or Circuits Using a Laser Printer

Appendix II: Preliminary Ideas: Microwave Connectors for Printed Circuits and Antennas

A2.1 Specification

A2.2 Adapters

A2.3 SMA Probe/Launcher for Microstrip Circuits and Antennas

A2.4 Maintenance

Index

Title Page

Preface

Microstrip technology has been popular for microwave and millimeter wave applications since the 1970s and recently has taken off, with the tremendous growth in communications, wireless, as well as space-borne/airborne applications, although the concept dates back to 1952 [1]. The basic microstrip configuration is very similar to a printed circuit board (PCB) used for low frequency electronic circuits. It constitutes a low-loss thin substrate, both sides being coated with copper film. Printed transmission lines, patches, etc. are etched out on one side of the microstrip board and the other copper-clad surface is used as the ground plane. In between the ground plane and the microstrip structure, a quasi-TEM electromagnetic wave is launched and allowed to spread.

Such a structure offers some unique basic advantages such as low profile, low cost, light weight, ease of fabrication, suitability to conform on curved surface, etc. All these have made microstrip technology attractive since the early phase of its development.

Within a year of the pioneering article “Microstrip – a new transmission technology for the kilomegacycle range” appearing [1], Deschamps [2] had conceived of microstrip as “microwave antenna.” But its practical application started nearly two decades later. Howell [3] and Munson [4] may be regarded as the pioneer architects of microstrip antenna engineering.

These early developments immediately attracted some potential research groups and the following studies were mainly concerned with theoretical analysis of different patch geometries and experimental verifications [5–12]. A parallel trend also developed very quickly and some researchers tried to implement conventional antennas such as dipole, wire, aperture, etc. in planar form [13–16]. They are commonly referred to as printed circuit antennas or simply printed antennas. Their operations and characteristics are completely different from those due to microstrip patches, although microstrip patch antennas, in many papers, are casually called printed circuit antennas. The topic printed antenna had acquired tremendous importance by the late 1970s and a three-day workshop held at New Mexico State University in Las Crises in October, 1979 was dedicated to Printed Circuit Antenna Technology.

The developments in microstrip antennas that occurred up to the late1970s were documented by Bahl and Bhartia in their famous book [17], published in 1980. The analysis and design aspects were addressed in another book by James, Hall and Wood [18], published in 1981. A contemporary article by Carver and Mink [19] discussed the fundamental aspects of microstrip antennas and this is still regarded as a good review paper for a beginner.

More activities in the area grew gradually and many applications were realized. The suitability of deploying such lightweight low profile antennas in airborne and space-borne systems initiated major developments in microstrip array technology. With the development of mobile and wireless communications, microstrip and other printed antennas attained a new focus to serve in different technology from the mobile handset to base station antennas. General information, gathered from journals, symposia and conference articles, reveals that about 50% of the whole antenna community has been active in microstrip or printed antenna practice for the past two or three decades.

The first handbook [20] was published in 1989, nearly a decade after the first book by Bahl and Bhartia [17]. Within another five years, microstrip antenna research had attained a level of maturity as is reflected in the title and topics of the microstrip antenna books published around the middle of 1990s [21–23]. The edited volume by Pozar and Shaubert [21] contains some published articles bearing the results of contemporary interests, such as bandwidth enhancement approaches, analysis and design techniques, aperture coupling and other feeding methods, active integrated antennas, conformal and phased arrays, etc. Narrow impedance bandwidth appears an inherent limitation of the microstrip element. The research and consequent developments in bandwidth enhancement were documented in [22]. Lee and Chen [23] covered some key areas of advances reported up to 1997.

The growing need and interest in microstrip antenna designs are reflected in three design handbooks [24–26] published at close interval from 2001 to 2004. Compacting, along with bandwidth widening of printed antennas, has attracted worldwide interest to support new wireless technology since the beginning of this century and its importance was reflected in titles [27–32] which appeared between 2002 and 2007.

The book edited by Lee and Chen [23] was a timely effort to incorporate major technological developments that had occurred up to1997, under the same cover. Since then, more than a decade has passed during which many new trends, techniques and applications in planar antenna technology have been developed. For example, RFID (Radio Frequency Identification) is an ideal example to showcase the need to this day. This application needs low cost antennas, printed on paper or very thin substrate. Another example is printed antenna using unconventional and new innovations, such as using metamaterials and defected ground structures (DGSs). Replacing a large parabolic dish with a flat microstrip array with a special feeding mechanism is also a new area of activity. The design of small ultrawideband (UWB) antennas with good performance is a challenging area. Antenna for the body area network is another interesting new topic.

From our long experience in teaching and mentoring doctoral and post-doctoral students and working with practicing engineers, we certainly feel there is a need for a book that is to address more recent topics of microstrip and printed antennas. We have chosen some topics that have recently been developed or have considerably advanced during the past decade and at the same time appear to be important to the new generation of researchers, developers and application engineers. We shared the ideas with some of our colleagues and friends who are the real technical experts and potential developers in those selected topics. They fully agreed with our views, gave valuable suggestions and delivered on their promise to contribute. Our collaborative efforts have finally culminated in the present title.

As indicated by the title, the focus is on the New Trends, Techniques and Applications of Microstrip and Printed Antennas. The chapters are organized as follows: Chapters 1–4 address advances in design, analysis, and optimization techniques, Chapters 5–10 focus on some important new techniques and applications, Chapters 11 and 12 deal with engineered materials applied to printed antenna designs, and finally Chapter 13 addresses advanced methods and designs of printed leaky wave antenna.

Chapter 1 deals with numerical techniques, which are essential in analyzing and designing planar antennas of any arbitrary geometry. A brief overview of the commonly used methods are discussed and the finite difference time domain (FDTD) technique is elaborated on, with special emphasis on the recent developments that occurred after 2003. Chapter 2 presents the advances in computer aided designs (CAD) of microstrip antennas reported during 2001 and onwards. The aim of this chapter is to provide accurate closed form expressions, which can be reliably used to compute essential design parameters such as operating frequency, input impedance and matched feed-location for a given antenna involving single or multiple dielectric layers. Chapter 3 embodies the Generalized Scattering Matrix (GSM) approach to analyzing the multilayer finite printed array structures. The methodology is demonstrated through examples. Chapter 4 deals with antenna optimization techniques. Optimization in terms of performance, size and cost is discussed and the basic concept of stochastic optimization techniques is demonstrated.

Chapter 5 describes microstrip reflectarray technology, its general principle, design, operation, and applications. Microstrip's inherent demerit of narrow bandwidth is dealt with in terms of spatial and frequency dispersions and some of the techniques to suppress these factors are presented. Chapter 6 deals with Reconfigurable Microstrip Antennas, which use switches, tunable materials, or control circuitry to give additional degrees of operational freedom or to make a single element operative in multiple frequencies. A wide variety of reconfigurability is discussed. The emerging trends and directions for future research have also been indicated.

Chapter 7 describes wearable antennas for body area networks. The properties of the human body in terms of electromagnetic radiations and the performance of multiple antenna systems in presence of the human body are described. Chapter 8 presents printed wireless antennas. These include three primary configurations: microstrip patch, slot, and monopole showing multiband, wideband, or ultra wideband performances. Significant developments reported since 2000 are addressed in this chapter. Chapter 9 deals with printed antennas for RFID tags. An RFID system may be one of the following types: active, passive, or in between of these two, based on the nature of the devices used and also any of LF, HF, or UHF type based on the frequency of operations. Passive tags operating at UHF place several specialized requirements on the associated antenna structures and these are described in this chapter. Chapter 10 deals with printed antennas for ultra-wideband (UWB) applications. This incorporates the innovative technologies to minimize ground plane effects on the performance of small printed antennas.

Chapter 11 presents applications of metamaterials to planar antenna and radiative system designs. Both leaky wave and resonant metamaterial antennas are discussed with special emphasis on their recent and somewhat exotic applications. Chapter 12 deals with defected ground structures (DGS) applied to microstrip antennas. This is a recently developed topic and all the major developments that have occurred after 2002 are discussed, indicating the future scope of development. This is probably addressed here as an exclusive book chapter for the first time. Chapter 13 concludes with printed leaky wave antennas. It includes both theory and some applications based on recent advances in technology.

Each chapter is designed to cover the range from fundamental concepts to the state-of-the-art developments. We have tried to satisfy a wide cross-section of readers. A student or a researcher may consider this a guide book to understanding the strength and weaknesses of the contemporary topics. To a practicing engineer, we hope that the book will be a ready reference to many new areas of applications. To an educator, the book appears as a comprehensive review and a source of up-to-date information.

Our sincere efforts and exercise will be successful if our readers appreciate and find it useful for their respective purposes.

Debatosh Guha

Yahia M. M. Antar

References

1. D. D. Greig and H. F. Engleman, “ Microstrip – a new transmission technology for the kilomegacycle range,” Proc. IRE, vol. 40, pp. 1644–1650, 1952.

2. G. A. Deschamps, “ Microstrip microwave antennas,” presented at the 3rd USAF Symp. on Antennas, 1953.

3. J. Q. Howell, “ Microstrip antennas,” Dig. IEEE Int. Symp. Antennas Propagat., pp. 177–180, Dec. 1972.

4. R. E. Munson, “ Conformal microstrip antennas and microstrip phased arrays,” IEEE Trans. Antennas Propagat., vol. 22, pp. 74–78, 1974.

5. T. Itoh and R. Mittra, “ Analysis of microstrip disk resonator,” Arch. Elek. Ubertagung, vol. 21, pp. 456–458, Nov. 1973.

6. T. Itoh, “ Analysis of microstrip resonator,” IEEE Trans. Microwave Theory Tech., vol. 22, pp. 946–952, Nov. 1974.

7. A. Derneryd, “ Linearly polarized microstrip antennas,” IEEE Trans. Antennas Propagat., vol. 24, no. 6, pp. 846–851, 1976.

8. G. Dubost, M. Nicolas and H. Havot, “ Theory and applications of broadband microstrip antennas,” Proc. 6th European Microwave Conference, pp. 275– 279, 1976.

9. P. Agrawal and M. Bailey, “ An analysis technique for microstrip antennas,” IEEE Trans. Antennas Propagat., vol. 25, no. 6, pp. 756–759, 1977.

10. W.F. Richards, Y.T. Lo and D. D. Harrison, “ Improved theory for microstrip antennas,” Electronics Letters, vol. 15, no. 2, pp. 42–44, 1979.

11. Y.T. Lo, D. Solomon and W. Richards, “ Theory and experiment on microstrip antennas,” IEEE Trans. Antennas Propagat., vol. 27, no. 2, pp. 137–145, 1979.

12. P. Hammer, D. Van Bouchaute, D. Verschraeven and A. Van de Capelle, “ A model for calculating the radiation field of microstrip antennas,” IEEE Trans. Antennas Propagat., vol. 27, no. 2, pp. 267–270, 1979.

13. K. Keen, “ A planar log-periodic antenna,” IEEE Trans. Antennas Propagat., vol. 22, no. 3, pp. 489–490, 1974.

14. D.T. Shahani and Bharathi Bhat, “ Network model for strip-fed cavity-backed printed slot antenna,” Electronics Letters, vol. 14, no. 24, pp. 767–769, 1978.

15. Inam E. Rana and N. G. Alexopoulos, “ On the theory of printed wire antennas,” 9th European Microwave Conference, 1979, pp. 687– 691, 1979.

16. A. Mulyanto, and R. Vernon, “ A V-shaped log-periodic printed-circuit antenna array for the 1 to 10 GHz frequency range,” Antennas and Propagation Society Intl. Symp., 1979, vol. 17, pp. 392–395.

17. I. J. Bahl and P. Bhartia, Microstrip Antennas, Artech House, Dedham, MA, 1980.

18. J. R. James, P. S. Hall and C. Wood, Microstrip Antennas: Theory and Design, Peter Peregrinus, London, 1981.

19. K. Carver and J. Mink, “ Microstrip antenna technology,” IEEE Trans. Antennas Propagat., vol. 29, pp. 2–24, Jan. 1981.

20. J. R. James and P. S. Hall, Handbook of Microstrip Antennas, Peter Peregrinus, London, 1989.

21. D. M. Pozar and D. H. Schaubert, Microstrip Antennas, IEEE Press, New York, 1995.

22. J. F. Zürcher and F. E. Gardiol, Broadband Patch Antennas, Artech House, Boston, 1995.

23. K. F. Lee and W. Chen, Advances in Microstrip and Printed Antennas, John Wiley & Sons, Inc., New York, 1997.

24. R. Garg et al., Microstrip Antenna Design Handbook, Artech House, Boston, 2001.

25. R. Waterhouse, Microstrip Patch Antennas: A Designer's Guide, Springer, Berlin, 2003.

26. R. Bancroft, Microstrip and Printed Antenna Design, Noble Publishing, 2004.

27. Kin-Lu Wong, Compact and Broadband Microstrip Antennas, John Wiley & Sons, Inc., New York, 2002.

28. G. Kumar and K. P. Ray, Broadband Microstrip Antennas, Artech House, Boston, 2002.

29. Kin-Lu Wong, Planar Antennas for Wireless Communications, John Wiley & Sons, Inc., New York, 2003.

30. Zhi Ning Chen and Michael Yan Wah Chia, Broadband Planar Antennas: Design and Applications, John Wiley & Sons, Inc., New York, 2006.

31. Peter S. Hall and Yang Hao, Antennas and Propagation for Body-Centric Wireless Communications, Artech House, Boston, 2006.

32. Zhi Ning Chen (eds.), Antennas for Portable Devices, John Wiley & Sons, Inc., New York, 2007.

List of Contributors

Yahia M. M. Antar, Royal Military College, Canada

Jennifer T. Bernhard, University of Illinois at Urbana-Champaign, USA

Arun K. Bhattacharyya, Northrop Grumman Corporation, USA

Sujoy Biswas, Institute of Technology and Marine Engineering, India

Christophe Caloz, École Polytechnique, Montreal, Canada

Reza Chaharmir, Communication Research Centre Canada, Ottawa, Canada

Zhi Ning Chen, Institute for Infocomm Research, Singapore

Daniel Deavours, University of Kansas, USA

Daniel Dobkin, Enigmatics, USA

Ramesh Garg, Indian Institute of Technology, Kharagpur, India

Debatosh Guha, Institute of Radio Physics and Electronics, University of Calcutta, India

Peter S. Hall, University of Birmingham, UK

Yang Hao, Queen Mary College, University of London, UK

Samir F. Mahmoud, University of Kuwait, Kuwait

Rabindra K. Mishra, Electronic Science Department, Berhampur University, India

Xianming Qing, Institute for Infocomm Research, Singapore

Shie Ping Terence See, Institute for Infocomm Research, Singapore

Lotfollah Shafai, University of Manitoba, Canada

Jafar Shaker, Communication Research Centre Canada, Ottawa, Canada

Satish K. Sharma, San Diego State University, USA

Jawad Y. Siddiqui, Institute of Radio Physics and Electronics, University of Calcutta, India

Acknowledgments

Editing a book, like this, is a rare experience involving both liberty and responsibility. We came up with this idea in 2008 and started consulting with the experts who could be potential authors for different chapters of this book. The idea has turned into reality only due to the unstinted cooperation of the authors, who could dedicate time from their extremely busy schedules and contribute to different topics. We are grateful to all of them for their spontaneous help and support.

We would also like to express our thanks to a number of our colleagues, researchers and students who helped with many tasks throughout the process. Mr. Sujoy Biswas of Institute of Technology and Marine Engineering, India, Dr. Jawad Y. Siddiqui of the University of Calcutta, India (currently associated with the Royal Military College, Canada), Mr. Chandrakanta Kumar of the Indian Space Research Organization, and Mr. Anjan Kundu of University of Calcutta have extended their constant help and technical support throughout the whole process. We have also received help from some of our students: Sudipto Chattopadhyay of Siliguri Institute of Technology, India, Symon Podilchak of Queen's University and the Royal Military College, Canada, and Mr. David Lee of CRC in Ottawa. Dr. Somnath Mukherjee of RB Technology, USA, helped us tremendously in resolving the organization of the book. We have received constant help and support from Sarah Tilley, Anna Smart, and Genna Manaog of Wiley, which made our job easy. We are extremely grateful to all of them.

We cannot but acknowledge the ungrudging support and cooperation received from our families and from our respective Institutions: the University of Calcutta and the Royal Military College of Canada. It is always challenging to bring so many people from different parts of the world to work together on one task at the same time. We express our indebtedness to all members of this team for contributing to this volume in their different capacities.