Bio:

Sadasiva M. Rao received the Bachelors degree in electrical communication engineering from Osmania University in 1974, Masters degree in microwave engineering from Indian Institute of Sciences in 1976, and Ph.D. degree with specialization in electromagnetic theory from University of Mississippi in 1980.

Dr. Rao served as an Assistant Professor in the Department of Electrical Engineering, Rochester Institute of Technology from 1980 to 1985, Senior Scientist at Osmania University from 1985 to 1987, and as a Professor in the Department of Electrical and Computer Engineering, Auburn University from 1988 to 2009. He also held visiting Professorships at University of Houston (1987to 1988), Osmania University, and Indian Institute of Science. Presently, he is with the Radar Division, Naval Research Laboratory, Washington, DC. Dr. Rao worked extensively in the area of numerical modeling techniques as applied to Electromagnetic/Acoustic Scattering. He and his team at the University of Mississippi, were the original researchers to develop the planar triangular patch model and to solve the problem of EM scattering by arbitrary shaped conducting bodies. For this work, he received the best paper award for the period 1979 to 1981 from SUMMA Foundation. He published/presented over 150 papers in international journals/conferences. For his contributions in numerical electromagnetic problems, he was awarded the status of Fellow of IEEE. Further, he was recognized as a HIGHLY CITED RESEARCHER by Thomson ISI in 2001.

Dr. Rao's research interests are in the area of numerical methods applied to antennas and scattering.

Presentation

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Abstract:

For scattering problems concerning arbitrary shaped bodies, the method of moments (MoM) has provided a practical means of solution using surface integral equations. Although there exist several numerical procedures to solve such MoM problems, the most popular of such schemes employs triangular patch modeling and Rao-Wilton-Glisson (RWG) vector basis functions. In this work, we examine the application of RWG functions for various situations, in frequency domain as well as in time domain involving: a) only PEC bodies, b) only dielectric bodies, and c) a combination of both conductor/dielectric bodies.  We investigate various expansion and testing schemes adopted for successful numerical implementation of the afore mentioned problems and analyze the circumstances necessitated to develop those schemes. We also look at a few recent numerical procedures which further extend the applicability of these functions and the method of moments itself to electrically large problems.

FDTD Analysis of In-body RF Communications Using Basic MATLAB Package

Bios:

Sergey N. Makarov (M’98–SM’06) earned his B.S./M.S./Ph.D./Dr. Sci. degrees at the St. Petersburg (Leningrad) State University, Russian Federation – Faculty of Mathematics and Mechanics. Dr. Makarov joined Institute of Mathematics and Mechanics at State St. Petersburg University in 1986 as a researcher and then joined the Faculty of State St. Petersburg University where he became a full professor (youngest full professor of the faculty) in 1996. In 2000 he joined the Faculty of Department of Electrical and Computer Engineering at Worcester Polytechnic Institute, MA where he became a full professor and director of the Center for Electromagnetic Modeling and Design in 2008. His current research interests include applied antenna design and computational electromagnetics.

 Gregory M. Noetscher (S’11) was born in Syracuse, NY.  He received the B.S. degree in biomedical engineering and the M.S. degree in electrical engineering from Worcester Polytechnic Institute in 2000 and 2005, respectively. Since 2003, Mr. Noetscher has worked on the Airdrop Technology Team at the U.S. Army Natick Soldier Research, Development and Engineering Center in Natick, MA Currently, Mr. Noetscher is working toward his PhD degree. His research interests include numerical modeling and applied electromagnetics.

Presentation

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A classic FDTD solver (Yee algorithm on a rectangular grid) capable of modeling of a TX/RX antenna link (small dipole, loop, patch, PIFA antennas) in the vicinity or inside a human body model is implemented in MATLAB®. We present results for standard (Ansoft/Ansys HFSS) and custom body meshes obtained with WB4 whole body scanner manufactured by Cyberware. Those meshes are projected onto the base rectangular grid using interpolation of the relative dielectric permittivity between FDTD nodes. The effect of different body shapes and body organs is quantified at certain VHF ad UHF frequencies. Special attention is paid to a 402 MHz carrier. 

Design, Fabrication, Simulation and Testing of Flexible Bow-Tie Antennas

Constantine A. Balanis (S'62 - M'68 - SM'74 - F'86 – LF'04) received the BSEE degree from Virginia Tech, Blacksburg, VA, in 1964, the MEE degree from the University of Virginia, Charlottesville, VA, in 1966, and the Ph.D. degree in Electrical Engineering from Ohio State University, Columbus, OH, in l969. From 1964-1970 he was with NASA Langley Research Center, Hampton VA, and from 1970-1983 he was with the Department of Electrical Engineering, West Virginia University, Morgantown, WV.  Since 1983 he has been with the Department of Electrical Engineering, Arizona State University, Tempe, AZ, where he is now Regents' Professor. His research interests are in computational electromagnetics, flexible antennas and High Impedance Surfaces (HIS/EBGs), smart antennas, and multipath propagation.  He received in 2004 a Honorary Doctorate from the Aristotle University of Thessaloniki, the 2005 IEEE Antennas and Propagation Society Chen-To Tai Distinguished Educator Award, the 2000 IEEE Millennium Award, the 1996 Graduate Mentor Award, Arizona State University, the 1992 Special Professionalism Award from the IEEE Phoenix Section, the 1989 IEEE Region 6 Individual Achievement Award, and the 1987-1988 Graduate Teaching Excellence Award, School of Engineering, Arizona State University.

            Dr. Balanis is a Life Fellow of the IEEE.  He is Chair, Awards and Fellows Committee, IEEE Antennas and Propagations Society (2009-present).  He has served as Associate Editor of the IEEE Transactions on Antennas and Propagation (1974-1977) and the IEEE Transactions on Geoscience and Remote Sensing (1981-1984), as Editor of the Newsletter/Magazine for the IEEE Geoscience and Remote Sensing Society (1982-1983), as Second Vice-President (1984) and member of the Administrative Committee (1984-85) of the IEEE Geoscience and Remote Sensing Society, and as Distinguished Lecturer (2003-2005), Chairman of the Distinguished Lecturer Program (1988-1991) and member of the AdCom (1992-95, 1997-1999) of the IEEE Antennas and Propagation Society.  He is the author of Antenna Theory: Analysis and Design (Wiley, 2005, 1997, 1982), Advanced Engineering Electromagnetics (Wiley, 1989) and Introduction to Smart Antennas (Morgan and Claypool, 2007), and editor of Modern Antenna Handbook (Wiley, 2008) and for the Morgan & Claypool Publishers,  series on Antennas and Propagation series, and series on Computational Electromagnetics.

Presentation

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Abstract:

The presentation will focus on the design, fabrication, simulation and measurements of two different flexible bow-tie antennas: a conventional and a modified one with reduced metallization.  The antennas are mounted on a flexible substrate which is fabricated at the Flexible Display Center (FDC) of Arizona State University (ASU).  The substrate is heat stabilized polyethylene naphthalate (PEN) which allows the antennas to be flexible.  The antennas are fed by a microstrip-to-coplanar feed network balun.

The reduction of the metallization is based on the observation that the majority of the current density is confined towards the edges of the regular bow-tie antenna.  Hence the center parts of the conventional bow-tie antennas are removed without compromising significantly its performance. The return losses and radiation patterns of the antennas are simulated with HFSS and the results are compared with measurements, for bow-tie elements on flat and curved surfaces.  The impact of the curvature is also examined.  The comparisons show that there is an excellent agreement between the simulations and measurements for both cases.  Furthermore, the radiation performance of the modified bow-tie antenna is verified to be very close to those of the conventional bow-tie by simulations and measurements.

In addition to the radiation characteristics of the antennas, the effects of the feeding structure and the conductor losses on the radiation performance of the antennas will be discussed. 

Low Cost ESAs for Army Applications

Dr. Steven J. Weiss graduated from The Rochester Institute of Technology with a Bachelor’s Degree in Electrical Engineering in 1985 and from the George Washington University with a Doctorate of Science (DSc.) in Electrophysics in 1995. 

He presently heads the antenna team at the Army Research Lab working on the development of antenna systems for applications as diverse as radar, satellite communications, and terrestrial communications.  His research areas also include specialized antennas for military applications for which he has been recognized for his outstanding contributions. His recent research interests have investigated metamaterial enhancements to antennas for military applications and the in-situ modeling to optimize antenna placement on platforms.

Dr. Weiss has taught evenings at the Johns Hopkins University since 2002 instructing courses in Antenna Systems (525.418) and Advanced Antenna Systems (525.738), and Intermediate Electromagnetics (525.405).

Dr. Weiss is a senior member of the IEEE holding memberships in the both the Antennas and Propagation and the Education Societies. He is also a member of the International Union of Radio Science (URSI) and the Applied Computational Electromagnetics Society (ACES.) Dr. Weiss has published numerous conference and journal papers with these professional affiliations. He is a fellow of the Washington Academy of Science and is a licensed professional engineer with the states of Maryland and Delaware

 Presentation

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Over the years the Army Research Laboratory has designed, prototyped and demonstrated a full spectrum of affordable scanning antenna concepts for multiple applications.  These concepts include a traditional electronic phase shifter for X-band compact network radars, Rotman lens beamformers for Ku band Terrestrial Communications and Ka band Multifunction RF systems and a W-band switch beam antenna for robotic perception.  This talk will give an overview of ARL developed beamformers as well as a discussion of some unique antenna designs created by the antenna team at the lab.

Seminar 1: Terminal antenna design: practical considerations
Seminar 2: Challenges in practical design of planar arrays     

Nowadays, the access to mobile communications not only through mobile telephones, but also other kind of portable devices such as notebooks or PDAs, equipped with PCMCIA cards, allows providing almost universal connectivity, with access to public or private networks. Therefore, both cellular standards, such as the GSM family and third generation standards such as UMTS, as well as unlicensed networks, like WLAN, should be accessible with a single device. However, the limited space foreseen for the antenna and the small overall size of the terminal are often the reason of the narrow band characteristics of the resulting antennas. This problem becomes even more serious when a multiband or an ultra-wideband antenna has to be designed. Also, only a careful design of the antenna taking into account the interaction both with the handset components and the human user can lead to satisfying solutions that fulfil the given requirements for mobile communications handsets. Their design is, however, no trivial task due not only to the extensive requirements of modern antennas but also to plethora of physical factors that impinge on their performance, such as the close proximity of electronic components.

However, in the design of antennas for commercial applications, the designer has to take into account many issues not directly related to the antenna itself. Antenna engineers have to interact with other departments, to satisfy all the requirements in terms of, for example, mechanical stability, aesthetical design or compliance testing. Thus, the design must be able to adapt the antenna concept to eventual changes in the device or the specifications. Although the use of powerful software packages has allowed to precisely simulate the antennas in such a complex environment, they are useless without an in-depth knowledge of electromagnetic theory and experience in solving such problems.

Dr. Martínez-Vázquez has been involved in the design of antennas for mobile communications both from the academic and the industrial point of view, which allows her to have a global view on the problems related to this topic.

1. Nowadays, the access to mobile communications not only through mobile telephones, but also other kind of portable devices such as notebooks or PDAs, equipped with PCMCIA cards, allows providing almost universal connectivity, with access to public or private networks. Therefore, both cellular standards, such as the GSM family and third generation standards such as UMTS, as well as unlicensed networks, like WLAN, should be accessible with a single device. However, the limited space foreseen for the antenna and the small overall size of the terminal are often the reason of the narrow band characteristics of the resulting antennas. This problem becomes even more serious when a multiband or an ultra-wideband antenna has to be designed. Also, only a careful design of the antenna taking into account the interaction both with the handset components and the human user can lead to satisfying solutions that fulfil the given requirements for mobile communications handsets. Their design is, however, no trivial task due not only to the extensive requirements of modern antennas but also to plethora of physical factors that impinge on their performance, such as the close proximity of electronic components.

However, in the design of antennas for commercial applications, the designer has to take into account many issues not directly related to the antenna itself. Antenna engineers have to interact with other departments, to satisfy all the requirements in terms of, for example, mechanical stability, aesthetical design or compliance testing. Thus, the design must be able to adapt the antenna concept to eventual changes in the device or the specifications. Although the use of powerful software packages has allowed to precisely simulate the antennas in such a complex environment, they are useless without an in-depth knowledge of electromagnetic theory and experience in solving such problems.

Dr. Martínez-Vázquez has been involved in the design of antennas for mobile communications both from the academic and the industrial point of view, which allows her to have a global view on the problems related to this topic.

2. The development of new multimedia services and intelligent sensor systems is progressing at a rapid pace and requires the use of agile antenna frontends that are compact, highly efficient and cost-effective. These antennas are rarely off-the-shelf solutions. On the contrary, custom-tailored solutions are usually required in order to optimise the performance, and facilitate the integration into the final product.

In many applications, the best compromise for an antenna solution with respect to cost and performance is a planar array. In general, a planar array can be defined as an antenna in which all of the elements are situated in one plane. The antenna elements themselves can be patches or other planar or buried structures. The range of applications of planar arrays include agile RF-frontends for mobile satellite terminals, radar systems for automotive and security applications, and millimetre wave point-to-point or point-to-multipoint radio links for multimedia wireless networks.

Real-life communications systems can include antenna arrays with only a limited number of transmitters and receivers as well as very large arrays with hundreds of receive and transmit channels. A skilful symbiosis of industrial development and innovative research projects is the key to provide cost-effective products. Some typical applications will be described in the next sections.

Considerable experience is required for the design and realisation of planar antenna arrays at microwave frequencies, especially when broadband solutions are demanded. It is not only necessary to develop innovative concepts beyond the standard patch design, but it also becomes unavoidable to cope with material and manufacturing tolerances when realising the antennas on soft and hard substrates. Special care has also to be invested in the RF-feeding network and the transition between antenna and RF-circuitry, as the latter can become a bottleneck at high frequencies, hence limiting the available bandwidth.

In order to provide cutting-edge solutions, it is important not only to develop systems based on state-of-the art antenna concepts. Fast and highly accurate EM solvers are indispensable tools to simulate the whole antenna system. Access to prototyping tools and accurate measurement facilities are also required. The seamless integration of all these services helps reduce the number of iterations to obtain high-performance antennas, thus leading to reduced development time. A complete, industrial solution for complex planar arrays must cover the whole development chain, starting with the conceptual design and the development of new concepts and solutions, going through the prototyping and optimisation process, including antenna characterisation and diagnosis, up to the preparation of line production and qualification phase. Some of the key steps will be discussed in this talk.

Emerging Conformal, Flexible Antenna Technologies for UAVs and Morphing Structures

BIO

Dr. Yakup Bayram is a CEO & Chief Technology Officer at PaneraTech, Inc., which is specialized in conformal antennas, wireless sensors and navigation solutions. Prior to his position at PaneraTech, Dr. Bayram was with The Ohio State University ElectroScience Laboratory (OSU-ESL) at Senior Research Associate capacity. During his tenure at OSU-ESL, Dr. Bayram has participated in and led research programs spanning conformal antennas to wireless sensors, electromagnetic interference, and wireless communications and propagation. He also served as the Principal Investigator for research and development efforts for two Air Force and NAVAIR funded projects for wireless strain sensing on Jet engine compressor and turbine blades. Dr. Bayram also served as the program coordinator for the AFOSR GameChanger program whose objective was to develop “Multifunctional Hybrid Composite Structures for Load Bearing Antennas for Unmanned Aerial Vehicles.”

Dr. Yakup Bayram also made significant contributions to the development of high frequency computational modeling of Electromagnetic Interference and Compatibility. He is author of a book on the subject "Computational Methods for High Frequency Electromagnetic Interference” and one of his publications received a prestigious IEEE Leo L. Beranek award in this field. He has over 40 journals and conference publications on topics ranging from innovative antennas to wireless sensors.

Dr. Bayram received his B.S. in Electrical Engineering from Bilkent University, Turkey in 2001 and M.S. and Ph.D. degrees in Electrical and Computer Engineering from The Ohio State University, USA, in 2004 and 2006, respectively. He also received his M.B.A degree from Fisher College of Business, The Ohio State University in 2007.

Dr. Bayram is a senior Member of IEEE, and recipient of the 2005 IEEE Leo L. Beranek Award for innovative contributions to the field at IEEE International EMC conference in Chicago. He is also the recipient of 2001 IEEE Regional Activities Achievement Board Award. He is an invited reviewer for six major research journals and books by Wiley&Sons Publisher. Dr. Bayram is also a recipient of merit-based Ashland Fellowship and The Frank Joseph Thomas Memorial Scholarship from Fisher College of Business.

ABSTRACT

Conformal and light-weight antennas are gaining significant interest with the proliferation of Unmanned Aerial Vehicles (UAVs). There has been limited success with integrating low frequency antennas into the UAV airframe. Low frequency antennas present severe technical challenges since they claim major real estate on the limited UAV airframe due to large wavelengths at low frequencies. Furthermore, increased co-site and co-channel interference due to tightly packed antennas on a limited real estate leads to further challenges integrating these antennas on the UAV platform. Therefore, conformal antennas are key to not only utilizing the UAV real estate more optimally but also reducing interference; thus, improving the antenna performance. These structures also enable device miniaturization via 3D integration of the antenna into a host structure.  For example, conformal antennas can be  woven into airframes and reinforced to become load-bearing as well. 

Bio

Carlo P. Domizioli (S'03-M'09) was born in Luton, U.K., on Nov. 7, 1980. He received the B.S. degree in electrical engineering from Tennessee Technological University, Cookeville, in May 2005, and the Ph.D. degree in electrical engineering from North Carolina State University, Raleigh, in Dec. 2009. Since Aug. 2009 he has been employeed as a communication systems engineer for Northrop Grumman Information Systems in Fairfax, VA. His areas of interest include channel modeling and receiver design for MIMO and OFDM wireless communication systems.

Abstract

Multiple-input, multiple-output (MIMO) systems combine the deployment of multiple antennas at both the transmitter and receiver with sophisticated signal processing to improve the performance of wireless communications. As with any communication system, developing an accurate yet mathematically tractable channel model is essential to analyzing the performance of actual systems. Prior studies of MIMO channel modeling have provided detailed models for fading correlation -- either due to the propagation environment or through mutual coupling between the antennas -- and how this correlation affects performance. On the other hand, relatively little attention has been paid to the noise correlation. In this talk we consider noise analysis and low-noise design for compact MIMO receivers. We begin by extending a circuit model for mutual coupling to include noise generated by theantennas, front-end amplifiers, and other components. Through analytical and numerical examples we demonstrate that the noise may be correlated, and that different noise sources may impact performance in profoundly different ways. Finally, we derive low-noise design theorems for MIMO front-ends from communication-theoretic principles

Directional Wireless Communications Networks

Bio

Christopher C. Davis is Professor of Electrical and Computer Engineering at the University of Maryland, College Park. He received the B.A. degree (with Honors) in Natural Sciences from the University of Cambridge in 1965, the M.A. degree from the University of Cambridge in 1970, and the Ph.D. degree in Physics from the University of Manchester in 1970. From 1973-1975 he was a Instructor/Research Associate at Cornell University, and from 1982-83 was a Senior Visiting Fellow at the University of Cambridge. He has been a recipient of the following Honors and Awards:  University of Maryland Distinguished Scholar-Teacher, 1989-90; Fellow of the Institute of Physics, 1989; AT&T/ASEE Award for Excellence in Engineering Education,1990; Fellow of the IEEE, 1993; Invention of the Year Award in Information Technology, University of Maryland, 2000. Professor Davis is the author of the widely used text “Lasers and Electro-Optics,” published by Cambridge University Press, and co-author with Jack Moore and Mike Coplan of the best selling text “Building Scientific Apparatus,” recently published in its 4th edition by Cambridge University Press.

He is also author or co-author of 14 chapters in books, over 205 refereed journal articles and 290 conference papers, and is the holder of twelve awarded and several pending patents. He is Conference co-Chair of the SPIE Free Space Laser Communications Conference, and is a frequent invited lecturer both nationally and internationally.

He has served as a scientific consultant to several US Government agencies and industry. He is a member of the IEEE Standards Coordinating Committee SCC-34 SC2, which deals with RF exposure from wireless devices.

Currently active research includes optical and RF directional wireless, real-time advanced surveillance systems with “event” detection, the optical properties of nanostructures where surface plasmons can be excited, near-field scanning optical microscopy, laser interferometry, dielectrometry, fiber sensors and biosensors, magnetooptics, optical trace detection, atmospheric turbulence, optical communication systems and devices, and biophysics.

His past research has covered gas lasers, photon counting, chemical lasers, molecular relaxation processes, diode-pumped solid-state lasers, laser noise and instabilities, injection locking of broad area laser diodes, nonlinear imaging of ferroelectric and ferromagnetic materials, and studies of the biological effects of non-ionizing radiation

Abstract

Broadcast wireless networks have no fixed topology and suffer from several problems. Data from a node in the network that is intended for another node in the network becomes in essence interference at other nodes for which the data is not intended. Broadcast networks do not scale. Directional wireless networks use technologies that range from optical to radio and send data only to nodes for which it is intended. They are essentially infinitely scalable and can have an extremely low probability of intercept and detection. Omnidirectional transmissions waste energy, and are detectable by any node within range. Consequently, such networks are easily detectable, although actual data may not be detectable if encrypted. Omnidirectional wireless networks do not use the spatial or spectral domains as efficiently as hybrid networks, which use a directional wireless backbone and omnidirectional clusters of edge nodes. Such networks have defined topologies, which can be controlled to optimize the performance of the network. This optimization can provide mobility management as well as providing a secure high data rate backbone. This talk will discuss some of the challenges involved in implementing these hybrid networks, including topics such as topology control, pointing, acquisition, and tracking of directional links, and novel methods of simulation.

Bio

Dennis Prather began his professional career by joining the US Navy in 1982, where he still serves in the reserves as an Engineering Duty Officer (0-5). After active duty, he received the BSEE, MSEE, and PhD from the University of Maryland in 1989, 1993, and 1997, respectively.  During this time he worked as a senior researcher engineer for the Army Research Laboratory, where he performed research on both optical devices and architectures for information processing. His efforts included work on the modeling, design, and fabrication of meso-scale optical elements and their integration with active opto-electronic devices, such as VCSELS, IR FPAs and semiconductor lasers. During this work he developed computational electromagnetic models for the analysis of aperiodic-subwavelength and nano-scale photonic devices. In 1997 he joined the Department of Electrical and Computer Engineering at the University of Delaware. Currently he is the College of Engineering Alumni Distinguished Professor and his research focuses on both the theoretical and experimental aspects of active and passive nano-photonic elements and their integration into various subsystems. To achieve this, his lab develops and refines coupled computational electromagnetic and quantum mechanical models as well as the associated nano-fabrication (with a specialty in electron beam lithography) and integration processes necessary for their demonstration. Specific devices and applications include: subwavelength structures, photonic crystal devices, high frequency optical modulators, meta-materials, and RF-Photonics.

Professor Prather is currently an Endowed Professor of Electrical Engineering, he is a senior member of the IEEE, Fellow of the Society of Photo-Instrumentation Engineers (SPIE) and a Fellow of the Optical Society of America (OSA).  He received the Outstanding Junior Faculty in the College of Engineering in 2000, the William J. Kastner Award for Naval Engineering Excellence, in 2000, as well as the National Science Foundation CAREER Award, in 1999 and the Office of Naval Research Young Investigator Award, in 1999. He has authored or co-authored over 300 scientific papers, holds over 40 patents, and has written 10 books/book-chapters.

Abstract.

In this talk Dr. Prather will present the development of an imaging system for millimeter waves (mmWs) as well as many of its advantages and applications in the defense and security markets. Imaging in the mmW spectrum offers many of the advantages common to infrared imaging, but allows for the ability to see through obscurants, such as blowing sand, fog, dust, smoke, and light rain. It also offers the ability to see through certain types of materials, like outer garments, fiberglass, drywall, and others. In the course of this talk, Dr. Prather will discuss some of the unique attributes of mmWs and some of the underlying technologies used to capture and process these signals into images. In particular, his approach involves the use of high-frequency photonic modulators, which convert mmWs onto and optical signal that can be more easily imaged. This requires the heterogeneous integration of organic, inorganic, RF photonic, metamaterials and optoelectronic devices. Component design and integration will be presented in the context of realizing integrated RF-Photonic modules that contain ultra-broad band antennas, low noise amplifiers, and photonic phase-only modulators. Fully integrated systems working at 35 and 94GHz are characterized and presented.