Registration for Tutorial I or II

• The registration fees for each of the full-day tutorials is S$350. To register for the Tutorial A or B, please click at the online registration system available.

• Two full-day tutorials are arranged by the ISAP06 Committee, both on November 1, 2006.

  • "Smart Antennas", by Professor Tapan K Sarkar from Syracuse University, Syracuse, New York, USA
    (A good number of registrations is received, and there are limited seats available now --- please hurry)
    Tapan K. Sarkar received the B.Tech. degree from the Indian Institute of Technology, Kharagpur, in 1969, the M.Sc.E. degree from the University of New Brunswick, Fredericton, NB, Canada, in 1971, and the M.S. and Ph.D. degrees from Syracuse University, Syracuse, NY, in 1975.

    　

    From 1975 to 1976, he was with the TACO Division of the General Instruments Corporation. He was with the Rochester Institute of Technology, Rochester, NY, from 1976 to 1985. He was a Research Fellow at the Gordon McKay Laboratory, Harvard University, Cambridge, MA, from 1977 to 1978. He is now a Professor in the Department of Electrical and Computer Engineering, Syracuse University. His current research interests deal with numerical solutions of operator equations arising in electromagnetics and signal processing with application to system design. He obtained one of the “best solution” awards in May 1977 at the Rome Air Development Center (RADC) Spectral Estimation Workshop. He received the Best Paper Award of the IEEE Transactions on Electromagnetic Compatibility in 1979 and in the 1997 National Radar Conference. He has authored or coauthored more than 280 journal articles and numerous conference papers and 32 chapters in books and fifteen books, including his most recent ones, Iterative and Self Adaptive Finite-Elements in Electromagnetic Modeling (Boston, MA: Artech House, 1998), Wavelet Applications in Electromagnetics and Signal Processing (Boston, MA: Artech House, 2002), Smart Antennas (John Wiley & Sons, 2003), and History of Wireless (John Wiley & Sons, 2005).
    　

    Dr. Sarkar is a Registered Professional Engineer in the State of New York. He received the College of Engineering Research Award in 1996 and the Chancellor’s Citation for Excellence in Research in 1998 at Syracuse University. He was an Associate Editor for feature articles of the IEEE Antennas and Propagation Society Newsletter (1986-1988), Associate Editor for the IEEE Transactions on Electromagnetic Compatibility (1986-1989), Chairman of the Inter-commission Working Group of International URSI on Time Domain Metrology (1990–1996), distinguished lecturer for the Antennas and Propagation Society from (2000-2003) and on the board of directors of ACES (2000-2006) and vice president of the Applied Computational Electromagnetics Society (ACES). He is currently a member of the IEEE Electromagnetics Award board and an associate editor for the IEEE Transactions on Antennas and Propagation. He is on the editorial board of Digital Signal Processing – A Review Journal, Journal of Electromagnetic Waves and Applications and Microwave and Optical Technology Letters. He is a member of Sigma Xi and International Union of Radio Science Commissions A and B.

    　

    He received Docteur Honoris Causa both from Universite Blaise Pascal, Clermont Ferrand, France in 1998 and from Politechnic University of Madrid, Madrid, Spain in 2004. He received the medal of the friend of the city of Clermont Ferrand, France, in 2000.
    　

  • "Dielectric Resonator Antennas: Theory and Design", by Professor Ahmed A. Kishk from University of Mississippi University, MS 38677, USA
    (Due to some reasons, this tutorial is now withdrawn --- the Committee apologizes for any inconvenience caused)

    Ahmed A. Kishk received the BS degree in Electronic and Communication Engineering from Cairo University, Cairo, Egypt, in 1977, and in Applied Mathematics from Ain-Shams University, Cairo, Egypt, in 1980.  In 1981 he joined the Department of Electrical Engineering, University of Manitoba, Winnipeg, Canada, where he obtained his M.Eng and PhD degrees in 1983 and 1986, respectively.

    From 1977 to 1981, he was a research assistant and an instructor at the Faculty of Engineering, Cairo University.  From 1981 to 1985, he was a research assistant at the Department of Electrical Engineering, University of Manitoba.  From December 1985 to August 1986, he was a research associate fellow at the same department.  In 1986, he joined the Department of Electrical Engineering, University of Mississippi, as an Assistant Professor. He was on sabbatical leave at Chalmers University of Technology during the 1994-1995 academic year. He is now a Professor at the University of Mississippi (since 1995).  He was an Associate Editor of Antennas & Propagation Magazine from 1990 to 1993.  He is now an Editor of Antennas & Propagation Magazine.  He was a Co-editor of the special issue on Advances in the Application of the Method of Moments to Electromagnetic Scattering Problems in the ACES Journal.  He was also an editor of the ACES Journal during 1997. He was an Editor-in-Chief of the ACES Journal from 1998 to 2001. He was the chair of Physics and Engineering division of the Mississippi Academy of Science (2001-2002). He was a guest Editor of the special issue on artificial magnetic conductors, soft/hard surfaces, and other complex surfaces, on the IEEE Transactions on Antennas and Propagation, January 2005.

    His research interest includes the areas of design of millimeter frequency antennas, feeds for parabolic reflectors, dielectric resonator antennas, microstrip antennas, soft and hard surfaces, phased array antennas, and computer aided design for antennas. He has published over 160 refereed Journal articles and book chapters.  He is a coauthor of the Microwave Horns and Feeds book (London, UK, IEE, 1994; New York: IEEE, 1994) and a coauthor of chapter 2 on Handbook of Microstrip Antennas (Peter Peregrinus Limited, United Kingdom, Ed. J. R. James and P. S. Hall, Ch. 2, 1989).  Dr. Kishk received the 1995 outstanding paper award for a paper published in the Applied Computational Electromagnetic Society Journal. He received the 1997 Outstanding Engineering Educator Award from Memphis section of the IEEE. He received the Outstanding Engineering Faculty Member of the 1998, 2001 Faculty research award for outstanding performance in research, and 2005 Faculty research award for outstanding performance in research. He received the Award of Distinguished Technical Communication for the entry of IEEE Antennas and Propagation Magazine, 2001.  He also received The Valued Contribution Award for outstanding Invited Presentation, “EM Modeling of Surfaces with STOP or GO Characteristics – Artificial Magnetic Conductors and Soft and Hard Surfaces” from the Applied Computational Electromagnetic Society. He received the Microwave Theory and Techniques Society Microwave Prize 2004. Dr. Kishk is a Fellow member of IEEE since 1998 (Antennas and Propagation Society and Microwave Theory and Techniques), a member of Sigma Xi society, a member of the U.S. National Committee of International Union of Radio Science (URSI) Commission B, a member of the Applied Computational Electromagnetics Society, a member of the Electromagnetic Academy, and a member of Phi Kappa Phi Society.

SUMMARY:  There have been a large number of papers appearing in the scientific literature which claims that the antenna theory need to go through a revolution and new antenna theory of the future has tremendous potential under the guise of MIMO and smart antennas which is going to revolutionize electromagnetic theory and communication systems and so on. However, this is rather surprising as Maxwell’s equations are one of the few equations of mathematical physics that has not gone through any changes since Hertz put them in the appropriate scalar form and Heaviside in the vector form over one hundred and twenty five years ago. This is one of the rare theories that has withstood the erosion and corrosion of progress. The objective of this presentation is to illustrate that an incomplete understanding of the Maxwellian physics can often lead to the wrong conclusions and could promise illusory designs. A few of them will be illustrated to start and initiate a dialog about the physical subtleties in the conception, analysis, and design of a wireless system. The topic will start with fundamental mathematical modeling, concept of diversity and how to employ ensemble averaging as its originator – James Clerk Maxwell, intended. It will also discuss the feasibility of baseband broadband communication and will describe adaptive processing techniques where the effect of near field scattering and mutual coupling between the antennas can be taken into account. Finally, a reciprocity based SISO system will be presented and contrasted in performance with a conventional MIMO system. 

We first start the presentation with how to solve the nonlinear vector electromagnetic adaptive processing problem in contrast to the scalar quasi-linear acoustic problem. This new adaptive methodology can also take care of the various electromagnetic interactions between the antenna array and the platform on which it is mounted in addition to mutual coupling and nonuniformity in the antenna element spacing. To accomplish this goal a single snapshot based direct data domain least squares method is proposed which does not require any information of the clutter or noise characteristics and can be implemented in real time on a DSP chip. The number of coherent interferers that this method can handle is identical to the conventional adaptive techniques which require a block of data, whereas the classical method can deal with a larger number of incoherent interferers. Conventional approach in the electromagnetic community to adaptive antennas had employed analog processing techniques. With the advent of the digital technology the adaptive processing techniques used the conventional detection based methodology developed earlier for radar. The advantage of using the digital techniques is that one can cancel interferers in the main lobe. However, the detection based methodology is difficult to implement in real time as one needs to form a covariance matrix of the data. Also the effect of the finite size antenna and the mutual coupling between the antennas and their surroundings had so far been neglected. The result is that one needs to carry out calibration before any processing of the data can be done and it is an important aspect of the processing that needs to be done repeatedly. However, in a modern high speed data flow environment what is necessary is a new approach to adaptive processing which is based on estimation rather than on detection which had been the primary approach in radar where the shape of the received signal is assumed to be known and dispersion do not play an important role. However, in a rich multipath environment, a detection based methodology is not the solution as we know there are many copies of the signal present and what we need to do is to estimate its correct value. In addition when an array operates in a near field environment it is not clear what antenna beam forming means as the antenna pattern can only be defined in the far-field! For an adaptive technique to operate in such complex dynamic electromagnetic environments we have proposed a Maxwellian approach to Adaptive Antenna [T. K. Sarkar, M. Wicks, M. Salazar-Palma and R. Bonneau, Smart Antennas, John Wiley & Sons, 2003]. The advantage of this approach is that it is quite amenable to a dynamic environment as we operate on a single snapshot of the data. It is rather important to note that for coherent interferers, the available degrees of freedom using a single snapshot of the data is identical to the conventional covariance based method of using multiple snapshots. In addition it is faster than the conventional methods by an order of magnitude and in addition no statistical knowledge of the clutter is necessary in the computation of this least squares solution.  The following FIVE topics will be covered:

Topic 1. A Direct Data Domain Least Squares Approach to Adaptive Processing

The presentation will present a direct data domain least squares approach to adaptive processing without forming a covariance matrix which at least an order of magnitude faster than the stochastic methods, if and when they converge. Examples will be presented on the accuracy and efficiency of this technique over conventional stochastic methods for performing STAP processing using real measured data on an airborne platform called the MCARM data set.

Topic 2. Adaptive Processing Using Directive Elements in the Presence of Near-Field Scatterers

The talk will focus on how to adaptive processing using real antennas particularly when they are operating in a real environment in the presence of mutual coupling and other near field scatterers.

Topic 3. Broadband Baseband Communication: Fact or Fiction!

Current communication theory does not take the effect of antennas into account when talking about broadband – the result is a perfect recipe for failure- and the promise of baseband and broadband can only be addressed when the effects of sensors are appropriately accounted for. It will be shown that one can get a perfectly dispersionless channel once attention is paid to the physics of the problem which is sadly lacking in the present methodologies. 

Topic 4. Transmission and Reception by Ultrawideband Antennas in the Time Domain

Impulse response of antennas in the time domain will be discussed. It will be shown that one needs a new paradigm to look at antennas in the time domain as opposed to in the frequency domain. Examples of various wideband antennas including the century bandwidth antenna, impulse radiating antenna  and others will be presented.

Topic 5. Signal Enhancement in a Near Field MIMO Environment Through Adaptivity on Transmit

The definition of channel capacity a la Shannon is incomplete for the vector electromagnetic problem. The goal will be to address how to handle the vector electromagnetic problem as opposed to the scalar electromagnetic problem. The power spectral density which provides the basis for the scalar acoustics problem really does not hold in electromagnetics as the power in electromagnetics is defined by both the voltage and the current and not exclusively by either one, which may hold only for special cases. It is well known in electrical engineering that power in a RLC circuit cannot be obtained from only the voltage or the current. In addition the use of real antennas instead of point sources will drastically change the philosophy.

Tutorial II: "Dielectric Resonator Antennas: Theory and Design"
     (Due to some reasons, this tutorial is now withdrawn --- the Committee apologizes for any inconvenience caused)
　

Abstract: Recently, interest in dielectric resonator antennas has increased because of their attractive features such as small size, high radiation efficiency (98%), wide bandwidth, and high power capability for radar applications and base stations.  The dielectric resonator antenna is made from high dielectric constant materials and mounted on a ground plane or on a grounded dielectric substrate of lower permittivity.  The short course will start by an overview for the development of the dielectric resonator antennas.  The theory of operation will be discussed step by step to provide basic understanding.  The discussion is provided in simple forms to satisfy audience of different background levels. Design curves will be provided for the circular disc and hemisphere dielectric resonators. Use of these models with other geometries is discussed. 

Different excitation mechanisms are demonstrates such as the probe, slot, image line and waveguides. Applications in dielectric resonator arrays are provided with discussion on the mutual coupling level and the wide scanning capabilities of the dielectric resonator array.  The array bandwidth limit is discussed based on the element size and the spacing between the array elements. 

The problems related to the practical implementations are considered.  Results of a numerical study pertaining to the effect of an air gap, between the dielectric disc and the ground plane or an air gap surrounding the feed probe, on the input impedance and resonant frequency of a cylindrical DRA operating in the TM₀₁-mode or HEM₁₁-mode as a function of dielectric constant will be presented. Some of the numerical results are validated experimentally.

Formulation of the surface integral equations, derived from the equivalence principle, and the method of moments (MoM), are presented. Use of the MoM to compute the natural complex resonant frequency for a specified mode from which the radiation Q factor of the antenna and the (actual) real resonant frequency are obtained. Analytic expressions are obtained for the resonant frequency and the Q-factor for a circular disk resonating at different modes. Then the field distribution inside the dielectric disk is computed and plotted at the resonant frequency in order to determine the proper excitation mechanism that excites such a mode.

A formulation based upon MoM will be presented for the computation of input impedance of the DRA. The class of antennas modeled by this method consists of axially symmetric dielectric resonators fed by thin wire or a narrow slot in the ground plane of a microstrip line.  The formulation is general in that the feed structure may be interior or exterior to the dielectric resonator.  To demonstrate the utility of this technique, parametric studies are performed on a cylindrical DRA operating at frequencies, which excite the important HEM₁₁ resonator antenna mode.  The integrity of this technique is established both experimentally and numerically.

Finally, suggestions for size reduction of the DRA will be presented to demonstrate the flexibility of the DRA to satisfy the required small size for some applications.