Millimeter-wave Transceiver Chips with Antenna in Package

Prof. Quan Xue, South China University of Technology, China

3:00pm - 5:00pm, Thursday, August 17, 2023 @ E7-03-09, College of Design and Engineering

Professor Xue began his professional career in the University of Electronic Science and Technology of China (UESTC) in 1993 as a Lecturer, immediately after he obtained his Ph.D. In 1997, he became a Professor in UESTC then moved to Chinese University of Hong Kong to work as a Research Associate and then a Research Fellow. In 1999, he joined the City University of Hong Kong as Senior Scientific Officer, and then promoted as Associate Professor, Professor, and Chair Professor of Microwave Engineering. He also served the University as the Associate Vice President, the Director of Information and Communication Technology Center, and the Deputy Director of the State Key Lab of Millimeter Waves (Hong Kong). In 2017, he joined South China University of Technology. Now he is a Professor and serves as the Dean of the School of Electronics and Information Engineering, the Dean of the School of Microelectronics, and the Director of the Guangdong Key Laboratory of Terahertz and Millimeter Waves. He also served as the Chief Scientist of Antenna in the 2012 Labs of Huawei Technologies (2020-2023). His is a member of Chinese National 6G Technology General Expert Group. He has published over 400 internationally refereed journal papers and over 150 international conference papers. In addition, he has held more than 50 Chinese patents and more than 30 granted US patents. Prof. XUE's research interests include microwave/millimeter-wave/THz passive components, active components, antenna, microwave monolithic integrated circuits, etc

Harnessing the ''Fog'' of Ambient RF Waves

Professor Ross Murch, Hong Kong University of Science and Technology (HKUST)

9:30 am to 11:30 am, Thursday, August 17, 2023 @ E1-06-04, Engineering Block E1, CDE, NUS

Ross Murch is a Chair Professor in the Department of Electronic and Computer Engineering at the Hong Kong University of Science and Technology (HKUST). His research focus is creating new RF wave technology for making a better world and this includes RF imaging, energy harvesting, electromagnetic information theory, 6G, and reconfigurable intelligent surfaces. His unique expertise lies in his combination of knowledge from both wireless communication systems and electromagnetics. He is known for his work on multi-user multiple input multiple output (MU-MIMO) wireless communications, multi-user orthogonal frequency division multiplexing (MU-OFDM) and MIMO antenna design and is a Fellow of IEEE, IET and HKIE. He was Department Head at the Department of Electronic and Computer Engineering at HKUST between 2009 and 2015. Prof. Ross Murch has also been involved in IEEE activities including area editor for IEEE Transactions on Wireless Communications and Chair of the IEEE technology committee on wireless communications. He also enjoys teaching and has won several teaching awards. He received his Bachelor's and Ph.D. degrees in Electrical and Electronic Engineering from the University of Canterbury, New Zealand.

Better Light Distribution in Photocatalysts-Metamaterials and Waveguides

Dr. Joel Y. Y. Loh, University of Toronto, Canada

4:00pm - 5:00pm, 28 July 2022, Thursday, @ Mtg Rm S2-B (S1-B2b-77), EEE, Nanyang Technological University

Joel Y. Y. Loh is a postdoctoral associate at the University of Toronto, Electrical and Computing Engineering Department. He graduated with a bachelor's degree in Material Science and Engineering at Nanyang Technological University, Singapore, and switched to the Electrical Engineering department in University of Toronto for his M.A.Sc. and Ph.D. He was presented with the Connaught Scholar Award and the Award for Excellence in Research at the Advanced Photovoltaics and Photodevices Facility. He has contributed to and has been the recipient of several grants from the Natural Sciences and Engineering Research Council of Canada. He has recently published a book by the Royal Society of Chemistry titled "Energy Materials Discovery: Enabling a Sustainable Future". He is interested in developing metamaterials for energy applications and memristors for neuromorphic computing applications.

Distributed Phased Arrays: Challenges and Recent Progress

Prof. Jeffrey Nanzer, Michigan State University, USA

Tuesday, 17 May 2022, 9:30 am - 10:30 am, Singapore Time, @ Online

There has been significant research devoted to the development of distributed microwave wireless systems in recent years. The progression from large, single-platform wireless systems to collections of smaller, coordinated systems on separate platforms enables significant benefits for radar, remote sensing, communications, and other applications. The ultimate level of coordination between platforms is at the wavelength level, where separate platforms operate as a coherent distributed system. Wireless coherent distributed systems operate in essence as distributed phased arrays, and the signal gains that can be achieved scale proportionally to the number of transmitters squared multiplied by the number of receivers, providing potentially dramatic increases in wireless system capabilities. Distributed array coordination requires accurate control of the relative electrical states of the nodes. Generally, such control entails wireless frequency synchronization, phase calibration, and time alignment, but for remote sensing operations, phase control also requires high-accuracy knowledge of the relative positions of the nodes in the array to support beamforming.

This lecture presents an overview of the challenges involved in distributed phased array coordination, and describes recent progress on microwave technologies that address these challenges. Requirements for achieving distributed phase coherence at microwave frequencies are discussed, including the impact of component non-idealities such as oscillator drift on beamforming performance. Architectures for enabling distributed beamforming are reviewed, along with the relative challenges between transmit and receive beamforming. Microwave and millimeter-wave technologies enabling wireless phase-coherent synchronization are discussed, focusing on technologies for high-accuracy internode ranging, wireless frequency transfer, and high-accuracy time alignment. The lecture concludes with a discussion of open challenges in distributed phased arrays, and where microwave technologies may play a role.

Terahertz Communications at 300 GHz: Devices, Packages and System

Prof. Ho-Jin SONG, Pohang University of Science and Technology, South Korea

Tuesday, 10 December 2019, 10:00am – 11:30am@ Seminar Room 8D-1, Level 8, Temasek Laboratories, National University of Singapore

Recent progress in semiconductor devices on compound semiconductor or silicon substrates has made it possible to produce more power and receive a signal with less noise at THz frequencies. Various integrated circuits for the THz radio front-end functional blocks, including power and low-noise amplifiers, modulators and demodulators, and oscillators, have been demonstrated in the last decade. In the first experimental demonstration conducted in 2004, bulky instruments originally developed for THz spectroscopy were used to transmit pulsed THz signals carrying a 7-kHz bandwidth audio signal across a short free space. However, recently, there have been several successful demonstrations of multi-Gbps data transmissions at THz frequencies with state-of-the art devices and components. In this talk, the first prototype of a THz wireless communications system designed under the ‘touch-and-go’ scenario will be presented. I clarify the concept of the KIOSK data downloading system, cover some considerations in this work, and present a brief link-budget plan. We will then overview technologies for implementing THz components operating at 300 GHz and their performance, followed by preliminary investigation of the channel responses and the experimental demonstration results. At the end of the presentation, we will discuss several issues that need to be addressed for the future of the THz communications systems, in terms of system architectures, packagings and potential applications.

Unconventional Array Design - Fundamental and Advances

Professor Andrea MASSA, University of Trento, Italy

Tuesday, 10 December 2019, 4:00pm – 5:30pm@ Mtg Rm S1-C (S1-B1c-111), EEE, Nanyang Technological University

Antenna arrays are a key technology in several Electromagnetics applicative scenarios, including satellite and ground wireless communications, MIMO systems, remote sensing, biomedical imaging, radar, and radio astronomy. Because of their wide range of application, the large number of degrees of freedom at hand (e.g., type, position, and excitation of each radiating element), the available architectures (fully populated, thinned, clustered, etc.), and the possible objectives (maximum directivity, minimum sidelobes, maximum beam efficiency, etc.), the synthesis of arrays turns out to be a complex task which cannot be tackled by a single methodology. Despite this wide heterogeneity, most of the synthesis approaches share a common theoretical framework which is of paramount importance for all engineers and students interested in such a topic. Moreover, this is also true for innovative methodologies aimed at the design of "unconventional arrays" (i.e., based sparse, thinned, conformal, clustered, overlapped, interleaved architectures, both in the frequency and in the time domain), which are currently receiving a great attention from the academic and industrial viewpoint. The objective of the talk is therefore firstly to provide the attendees the fundamentals of Antenna Array synthesis, starting from intuitive explanations to rigorous mathematical and methodological insights about their behavior and design. Recent synthesis methodologies aimed at "unconventional architectures" (i.e., architectures close to the real‐applications and operative non‐ideal constraints/guidelines) will be then discussed in detail, with particular emphasis on innovative layouts for very large arrays.

Differential Microstrip Antennas

Professor Yueping ZHANG, Nanyang Technological University, Singapore

Friday, 6 September 2019, 10:00am – 11:30pm@ Lecture Theatre 4 (2.404, Building 2, Level 4), SUTD

The earliest antennas implemented by Hertz for the discovery of radio waves were dipole and loop. They are differential. It was Marconi who introduced the ground concept into antennas and realized single-ended monopole antennas for wireless transmission. Compared with differential antennas, single-ended antennas have smaller size and therefore single-ended antennas have dominated in antenna designs. Compared with single-ended circuits, differential circuits permit higher linearity and lower offset and make them immune to power supply variations, temperature changes, and substrate noise. As a result, differential circuits have dominated in integrated circuit designs. Differential circuits call for differential antennas. This is particularly essential in highly-integrated system-on-chip and system-in-package solutions where the system ground plane may be much smaller than one free-space wavelength. Differential antennas perfectly marry (match) with differential circuits. No lossy balanced/unbalanced conversion circuit is needed. As a result, the receiver noise performance and transmitter power efficiency are improved.

In this lecture, I present differential microstrip antennas with an emphasis on the comparison of them with single-ended counterparts. First, I extend the well-known cavity model for the single-ended microstrip antennas to analyze the input impedance and radiation characteristics of differential microstrip antennas. Then I examine the design formulas to determine the patch dimensions and the location of the feed point for single-ended microstrip antennas to design differential microstrip antennas. It is shown that the patch length can still be designed using the formulas for the required resonant frequency but the patch width calculated by the formula usually needs to be widen to ensure the excitation of the fundamental mode using the probe feeds. The condition that links the patch width, the locations of the probe feeds, and the excitation of the fundamental mode is the electrical separation, which is a new and unique concept specifically conceived for the design of differential microstrip antennas. Next, I turn to the miniaturization of differential microstrip antennas and discuss some latest achievements. Finally, I summarize the lecture and provide recommendations.

Millimeter-Wave In-Package Antennas

Professor Yueping ZHANG, Nanyang Technological University, Singapore

Thursday, 5 September 2019, 2.00pm – 3:00pm@ Seminar Room, Level 15 Connexis (North Tower), Fusionopolis

Antenna-in-package (AiP) technology, in which there is an antenna (or antennas) with a transceiver die (or dies) in a standard surface-mounted device, represents an important antenna technology achievement in recent years. AiP technology has been widely adopted by chip makers for 60-GHz radios and gesture radars. It has also found applications in 77-GHz automotive radars, 94-GHz phased arrays, 122-GHz imaging sensors, and 300-GHz wireless links. It is believed that AiP technology will also provide elegant antenna solutions to fifth generation and beyond operating in the lower millimeter-wave (mmWave) bands. Thus, one can conclude that AiP technology has emerged as the mainstream antenna and packaging technology for various mmWave applications. This lecture will start with a review of basic packaging ideas for AiP technology. Then it will focus on the co-design of antennas and packages. It will show that the antenna choice is usually based on those popular antennas that can be easily designed for the application; that the package choice is governed by the Joint Electron Device Engineering Council (JEDEC) for automatic assembly; and that the materials and processes choices involve tradeoffs among constraints such as electrical performance, thermo mechanical reliability, compactness, manufacturability, and cost. The talk also shows a probe-based setup to measure impedance and radiation of mmWave in-package antennas. It goes on to give AiP examples implemented, respectively, in different materials and processes. Finally, the lecture will present some recommendations on research topics to further the state of the art of AiP technology.

Terminal Antenna Design for Future Wireless

Prof. Buon Kiong Lau, Lund University, Sweden

11:00am – 12:00noon, Monday, 8 January, 2018@ E5-02-32, Engineering Block E5, Faculty of Engineering, NUS

Massive MIMO, full-dimension (FD) MIMO, millimeter-wave and small cells are some popular candidates for the 5th generation (5G) wireless communication systems. However, as much as these technologies present exciting new challenges for antenna design, the conventional design framework is expected to remain, partly due to the current emphasis on non-antenna issues. Conventionally, terminal antennas are designed based on simple, and often unrealistic criteria, including an emphasis on antenna performance in free space. Moreover, the need for compact multi-antenna implementation makes it even more challenging to deliver efficient antenna designs. Though poor antenna performance in reality is largely overlooked for different reasons, future wireless systems with high performance requirements will greatly benefit from a more comprehensive antenna design paradigm.

In this lecture, I will start by giving an overview of conventional terminal antenna design and comment on its limitations. Then, I will outline current trends in terminal antenna design for 4G systems. I will then introduce a new antenna design paradigm that has the potential to dramatically improve 5G performance. In particular, the paradigm takes into account the interactions of the antenna system with its nearfield and farfield surroundings and provides a powerful framework to optimize these interactions. Finally, I will provide some practical techniques to take advantage of this design paradigm, where each technique offers promising performance gains over the state-of-the-art.

Multiphysics Modeling in Computational Electromagnetics: Challenges and Opportunities

Professor Jian-Ming Jin, University of Illinois at Urbana-Champaign, USA

Thursday, 23 February 2017, 4.00pm – 5:30pm@ Meeting Room S2-B2 (S2-B2b-77), School of EEE, NTU

As computational methods for solving Maxwell’s equations become mature, the time has come to tackle much more challenging multiphysics problems, which have a great range of applications in sciences and technologies. In this presentation, we will use five examples to illustrate the nature and modeling of multiphysics problems. The first example is related to electromagnetic hyperthermia, which requires solving electromagnetic and bio-heat transfer equation for the planning and optimization of the treatment process. The second concerns the heat problem in integrated circuits due to electromagnetic dissipated power, which requires an electrical-thermal co-simulation. The third example considers modeling of monolithic microwave integrated circuits, which consist of both distributive and lumped circuit components. The fourth is the simulation of vacuum electronic devices using the particle-in-cell method, which solves Maxwell’s equations and particle kinetic equation, and the last example simulates the air and dielectric breakdown in high-power microwave devices by coupling electromagnetic modeling with various plasma models. With these examples, we will discuss the methodologies and some of the challenges in multiphysics modeling.

Many names, many advantages – Are resonant cavity antennas the killer planar space-saving approach to get 15-25 dBi gain?

Professor Karu P. Esselle, MACQUARIE UNIVERSITY, AUSTRALIA

24 February 2017, Friday, 11am to 12pm @ E5-02-32, Engineering Block E5, Faculty of Engineering, NUS

No other antenna concept has more names. At present these antennas are known as Fabry-Perot cavity resonator antennas, Partial Reflector Surface (PRS) based antennas, Electromagnetic Band Gap (EBG) Resonator antennas (ERAs) and Two-Dimensional Leaky-Wave Antennas, and more names are forthcoming. Yet they all have more or less the same configuration consisting of a resonant cavity, formed between a partially reflecting superstructure and a fully reflecting (ground) plane. The resonant cavity is excited by a small feed antenna. Hence, they are referred to as resonant cavity antennas (RCAs) in this presentation. Since the concept of using a “partially reflecting sheet array” superstructure to significantly enhance the directivity was disclosed by Trentini in 1956, it has been an attractive concept to several antenna researchers for several reasons, including its theoretical elegance, relationships to other well-researched area such as leaky-waves, EBG, frequency selective surfaces and metasurfaces, and practical advantages as a low-cost simple way to achieve high-gain (15-25 dBi) from an efficient planar antenna without an array, which requires a feed network. The RCA concept is one of the main beneficiaries of the surge of research on electromagnetic periodic structures in the last decade, first inspired by EBG and then to some extent by metamaterials. As a result, RCAs gained a tremendous improvement in performance in the last 10 years, in addition to other advantages such as size reduction. As an example, achieving 10% gain bandwidth from such an antenna with a PSS was a major breakthrough in 2006 but now there are prototypes with gain bandwidths greater than 50%. Until recently most RCAs required an area in the range of 25-100 square wavelengths but the latest extremely wideband RCAs are very compact, requiring only 1.5-2 square wavelengths at the lowest operating frequency. Once limited to a select group of researchers, these advantages have attracted many new researchers to RCA research domain, and the list is growing fast, as demonstrated by the diversity of authors in recent RCA publications. RCAs have already replaced other types of antennas, for example as feeds for reflectors. Have they become the killer planar alternative to 3D antennas such as horns and small reflectors? If not, what needs to be done to reach that stage?

This presentation will take the audience through historical achievements of RCA technology, giving emphasis to breakthroughs in the last 10 years. Special attention is given to methods that led to aforementioned bandwidth enhancement and area reduction, dramatic improvement of gain-bandwidth product and unprecedented gain-bandwidth product per unit area demonstrated by RCAs, both theoretically and experimentally. Several choices of superstructures are discussed. These superstructures include all dielectric superstrates with axial permittivity gradients and transverse permittivity gradients and printed superstructures also known as PSSs or metasurfaces. Due to ultra-compactness of modern designs and edge radiation becoming a significant player in the principle of operation, different optimisation methods and strategies have been developed to replace previous unit-cell based methods, which were only suitable for previous larger RCAs. In particular, optimisation of RCAs using automated optimisation methods, including evolutionary algorithms such as Genetic algorithms and Particle Swarm algorithms as well as statistical optimisation algorithms, is described, illustrating the improvements that have been achieved from such optimisations by the speaker’s team and others. Taking one step back, methods of designing phase correction structures (PCS) to enhance near-field phase uniformity, and hence far-field directivity, of conventional larger RCAs are presented, highlighting physical reasons for the phase non-uniformity. Both printed (metasurface-type) PCSs and all-dielectric PCSs are included in this discussion. The presentation will conclude with yet unresolved issues, which could be addressed in future research.

Compressive Sensing - Basics, State of the Art, and Advances in Electromagnetic Engineering

Prof. Andrea Massa, University of Trento, Italy

25 January 2017, 1530-1700 hrs @ Franklin Seminar Room, Institute for Infocomm Research (I2R), Fusionopolis 1, Level 11, Connexis South Tower
The widely known Shannon/Nyquist theorem relates the number of samples required to reliably retrieve a "signal" to its (spatial and temporal) bandwidth. This fundamental criterion yields to both theoretical and experimental constraints in several Electromagnetic Engineering applications. Indeed, there is a relation between the number of measurements/data (complexity of the acquisition/ processing), the degrees of freedom of the field/signal (temporal/spatial bandwidth), and the retrievable information regarding the phenomena at hand (e.g., dielectric features of an unknown object, presence/position of damages in an array, location of an unknown incoming signal).
The new paradigm of Compressive Sensing (CS) is enabling to completely revisit these concepts by distinguishing the "informative content" of signals from their bandwidth. Indeed, CS theory asserts that one can recover certain signal/phenomena exactly from far fewer measurements than it is indicated by Nyquist sampling rate. To achieve this goal, CS relies on the fact that many natural phenomena are sparse (i.e., they can be represented by few non-zero coefficients in suitable expansion bases), and on the use of aperiodic sampling strategies, which can guarantee, under suitable conditions, a perfect recovery of the information content of the signal.
Despite its recent introduction, the application of CS methodologies Electromagnetics has already enabled several innovative design/synthesis methodologies and retrieval/diagnosis methods to be developed.
In this framework, this talk is aimed at reviewing the fundamentals of the CS paradigm, specifically focusing on the applicability conditions, requirements, and guidelines for EM applications. Moreover, it is aimed at illustrating the state-of-the-art and the most recent advances in Electromagnetic Engineering (including application of CS to antenna synthesis and diagnosis, direction-of-arrival estimation, inverse scattering, and radar imaging), as well as at envisaging possible future research trends and challenges within CS as applied to Electromagnetics.
Current Research and Development of Wireless Power Transfer via Radio Waves and the Application

Professor Naoki Shinohara, Kyoto University, Japan

9 November 2016, 1400-1530 hrs @ Franklin Seminar Room, Institute for Infocomm Research (I2R), Fusionopolis 1, Level 11, Connexis South Tower
Theory, technologies, applications, and current R&D status of the wireless power transfer (WPT) will be presented. The talk will cover both the far-field WPT via radio waves, especially beam-type and ubiquitous-type WPT, and energy harvesting from broadcasting waves. The research of the WPT was started from the far-field WPT via radio waves, in particular the microwaves in 1960s. In recent years, this became a hot topic again due to the rapid growth of wireless devices. Theory and technologies of antenna and circuits will be presented in case of beam-type and ubiquitous-type WPT. The industrial applications and current R&D status of the WPT via radio waves will be also presented.
Batteryless Wireless Medical Devices and Systems
Prof. J.-C. Chiao, University of Texas at Arlington

19 August 2016, 0900-1030 hrs @ Executive Seminar Room, S2.2-B2-53, School of EEE, NTU

The presentation focuses on the development of wireless micro devices and systems for medical applications at UT-Arlington. They are based on technology platforms such as wireless energy transfer for batteryless implants, miniature electrochemical sensors, nanoparticle modified surfaces, MEMS devices and wireless communication. An integrated wireless body network for chronic pain management will be discussed. The system provides an adaptive closed-loop for neurorecorders to recognize pain signals and neurostimulators to inhibit pain. Batteryless endoluminal sensing telemeter architecture will also be discussed with an esophagus implant for remote diagnosis of gastroesophageal reflux disease (GERD) and an endoscopically-implantable wireless gastro-stimulator for gastroparesis management. These applications enable new medicines to improve human welfare and assist better living.

Convex Optimization for Optimal Design and Analysis of Small Antennas
Prof. Mats Gustafsson, Lund University, Sweden
29 October 2015, 1500-1630 hrs @ Seminar Room E4-04-03, Engineering Block E4, Faculty of Engineering, National University of Singapore
Design of small antennas is challenging as the Q-factor, efficiency, and radiation resistance must be controlled simultaneously. In this presentation, convex optimization together with integral expressions of the stored electromagnetic energies are used to analyze many fundamental antenna problems. The solutions to the convex optimization problems determine optimal currents, offer insight for antenna design, and present performance bounds for antennas. We present several optimization formulations such as maximal gain Q-factor quotient, minimal Q for superdirectivity, minimal Q for given far field, and efficiency. The effects of antennas embedded in structures such as mobile phones are discussed. Results are shown for various antenna geometries and compared to state of the art designs showing that many antennas perform almost optimally.
Wireless Applications: From Electromagnetic to Multiphysics Designs
Prof. Wen-yan Yin, Zhejiang University, China
5 August 2015, 1400-1500 hrs @ Lecture Theatre 3, Singapore University of Technology and Design
The real world is inherently multiphysics. Electromagnetics, in particular, does not exist isolation during the design of various wireless passives and actives. Rather, heat transfer and other effects can make a big impact on the performance of RF devices for wireless communication, such as miniaturized filters, couplers, LDMOSFET- and GaAs HBT-based power amplifiers, etc. For this reason, R & D terms are now adopting methodologies and tools beyond the traditional electromagnetic simulation and design, by taking all relevant multiphysics effects into account. In this talk, some novel co-simulation and co-design methods, based on both electromagnetics and multiphysics, will be presented in the development of substrate integrated waveguide (SIW)-based filters, LDMOSFET and GaAs HBT power amplifiers, vertically aligned single-walled carbon nanotube contacted phase change memory array, and graphene-gated graphene-GaAs Schotky junction field effect solar cell, where the design targets of miniaturized size, low loss, high efficiency, and high reliability  are achieved in some appropriate and practical ways.
Antenna Systems for 21st Century Satellite Communication Payloads
Dr. Sudhakar K. Rao, Northrop Grumman, USA
26 June 2015, 1615-1730 hrs @ Executive Seminar Room (S2.2-B2-53), School of EEE, NTU
The 21st century has so far seen several new satellite services such as local-channel broadcast for direct broadcast satellite service (DBS), high capacity K/Ka-band personal communication satellite (PCS) service, hosted payloads, mobile satellite services using very large deployable reflectors, high power hybrid satellites etc. All these satellite services are driven by the operators need to reduce the cost of satellite and pack more capability into the satellite. Antenna sub-system design, mechanical packaging on the spacecraft, and RF performance become very critical for these satellites. This talk will cover recent developments in the areas of antenna systems for FSS, BSS, PCS, & MSS satellite communications. System requirements that drive the antenna designs will be presented initially with brief introduction to satellite communications. Typical block-diagrams of the satellite payload including antenna and repeater will be presented. Advanced antenna system designs for contoured beams, multiple beams, and reconfigurable beams will be presented. Contoured beam antennas using dual-gridded reflectors, shaped single reflectors, and shaped Gregorian reflectors will discussed. The figure of merit of these antennas using gain-area-product (GAP) will be addressed. Multiple beam antenna (MBA) concepts and their advantages compared to conventional contoured beams will be introduced. Various designs of the MBA for DBS, PCS, and MSS services will be discussed along with practical examples. Recent advances in feed technology and reflector technology will be addressed and few examples. Advances in multi-band antennas covering multiple bands will be presented. Reconfigurable antennas, phased array systems, and lens antennas will be discussed. Topics such as antenna designs for high capacity satellites, large deployable mesh reflector designs, low PIM designs, and power handling issues will be included. Introduction to remote sensing antennas with examples will be included in the talk. Advanced high power test methods for the satellite payloads will be addressed. Brief introductions to TT&C antennas, passive inter modulation products (PIM) and multipaction for satellite payloads will be given. Antenna test ranges and software tools required for test and design of 21st century satellite antennas will be presented. Future trends in the satellite antennas will be discussed. At the end of this talk, engineers will be exposed to typical requirements, designs, hardware, software, and test methods for various satellite antennas.
 
Spectral Element Method for Nanophotonics and Multiscale Computational Electromagnetics
Prof. Qing Huo Liu, Duke University, USA
26 June 2015, 1445-1600 hrs @ Executive Seminar Room (S2.2-B2-53), School of EEE, NTU
Nanophotonics is a major technological frontier with numerous new applications. However, a significant challenge in design optimization of nanophotonic devices is the huge computational costs in large-scale simulations. Advances in high-precision, high-efficiency computational methods will have significant impact on this emerging area. In this presentation, we will discuss our recent efforts to develop the spectral element method (SEM) for computational nanophotonics. We will demonstrate the applications of SEM in photonic crystals and plasmonics, and for nonlinear effects such as the second and third order harmonic generation. We will then discuss the application of the SEM in multiscale computational electromagnetics for system-level design problems. Such multiscale problems are often very challenging to solve; they remain a significant barrier to system-level sensing and design optimization for a foreseeable future. Multiscale problems often contain three electrical scales, i.e., the fine scale (geometrical feature size much smaller than a wavelength), the coarse scale (geometrical feature size greater than a wavelength), and the intermediate scale between the two extremes. Most existing commercial solvers are based on single methodologies (such as finite element method or finite-difference time-domain method), and are unable to solve large multiscale problems. We will present our recent work in solving realistic multiscale system-level EM design simulation problems in time domain. The discontinuous Galerkin method is used as the fundamental framework for interfacing multiple scales with finite-element method, spectral element method, and finite difference method. Numerical results show significant advantages of the multiscale method.
 
Metamaterials and Composites: Electromagnetic Description and Unexpected Effects
Prof. Ari Sihvola, Aalto University, Finland
5 March 2015, 1600-1730 hrs @ Executive Seminar Room (S2.2-B2-53), School of EEE, NTU
In the analysis of electromagnetic fields interacting with material structures, the response of medium is condensed in dielectric and magnetic material parameters, like permittivity, conductivity, and permeability. In complicated and anisotropic media, these material parameters may need to be generalized from scalar quantities into matrices, or equivalently dyadics. The complicated response of materials is very often of structural origin, in other words the manner in which a heterogeneous mixture is formed determines its macroscopic electromagnetic material parameters. This lecture deals with the variety of ways how one is able to characterize and effectively describe the macroscopic dielectric and magnetic behavior of composite materials with given properties of the constituents and the geometrical microstructure. Homogenization principles will be applied to analyze and understand mixtures that display very interesting properties that differ strongly from these of the constituent materials. This is the domain of metamaterials, and the talk will shed light into this new paradigm in electromagnetics.
 

Lecture 1: Metamaterials: Past, Present and Future

Lecture 2: Radio Analog Signal Processing for Tomorrow's Radio

Prof. Christophe Caloz, École Polytechnique de Montréal, Canada
23 May 2014, 1600-1800 hrs @ Level 15 Seminar Room, Institute for High Performance Computing, Connexis (North Tower), Fusionopolis

Lecture 1 (1600-1700 hrs):

In the history of humanity, scientific progress has frequently been associated with the discovery of novel substances or materials. Metamaterials represent a recent incarnation of this evolution. As suggested by their prefix “meta”, meaning “beyond” in Greek, metamaterials (artificial materials owing their properties to sub-wavelength but supra-atomic scatterers) even transcend the frontiers of nature, to offer unprecedented properties with far-reaching implications in modern science and technology. This talk presents some research highlights in electromagnetic metamaterials over the past decade, with emphasis on applications providing performances or functionalities that outperform state-of-the-art technologies. The first part of the talk reviews some history, principles and properties of metamaterials from a global perspective. The second part presents a series of microwave metamaterial applications exploiting these properties, in particular negative refraction, near-zero index propagation, coupling amplification, full-space scanning leakage radiation, and agile temporal and spatial dispersions. This part culminates with the introduction of the concept of radio real-time signal processing, enabled by “phasers” (components with fully designable group delay versus frequency responses), which might play a central role in tomorrow’s radio. The third part introduces magnet-less non-reciprocal metamaterials (MNMs), which have been recently invented and developed in the speaker’s group. While non-reciprocal gyrotropic materials, first reported by Faraday in 1845, have always required a biasing magnet to date, MNMs, which are composed of transistor-loaded rings mimicking electron-spin precession in ferrites, only require a biasing voltage, and are therefore fully compatible with semiconductor technology. This new class of metamaterials might therefore be considered a breakthrough and seem to have a strong potential for commercial electronic and photonic applications. Finally, the talk explores perspectives for next-generation of metamaterials, which will arguably be muli-scale (micro, nano, atomic) and multi-substance (e.g. semiconductors, ferroelectrics, magnetic nanoparticles, multiferroics, carbon nanotubes, graphene, etc.) in nature.

Lecture 2 (1700-1800 hrs):

Today's exploding demand for faster, more reliable and ubiquitous wireless connectivity poses unprecedented challenges in radio technology. To date, the predominant approach has been to put increasing emphasis on digital signal processing (DSP). However, while offering device compactness and processing flexibility, DSP suffers of fundamental limitations, such as poor performance above the K band, high-cost A/D conversion, low processing speed and high power consumption. Recently, Radio Analog Signal Processing (R-ASP) has emerged as a novel paradigm to potentially overcome these issues, and hence address the aforementioned challenges. R-ASP processes radio signals in their pristine analog form and in real time, using “phasers”. A phaser is a temporally – and sometimes also spatially – dispersive electromagnetic structure whose group delay is designed so as to exhibit the required (quasi-arbitrary) frequency function to perform a desired operation, such as for instance real-time Fourier transformation. Phasers can be implemented in Bragg-grating, chirped-waveguide, magnetostatic-wave and acoustic-wave technologies. However, much more efficient phasers, based on 2D/3D metamaterial structures and cross-coupled resonator chains, were recently introduced, along with powerful synthesis techniques. These phasers can manipulate the group delay of electromagnetic waves with unprecedented flexibility and precision, and thereby enable a myriad of applications in communication, radar, instrumentation and imaging, with superior performance or/and functionality. This talk presents an overview of R-ASP technology, including dispersion-based processing principles, historical milestones, phasing fundamentals, phaser synthesis, and many applications.

 
Towards Greener Smartphones with Microwave Measurements
Prof. Dominique Schreuers, University of Leuven, Belgium
9 December 2013, 1600-1730 hrs @ NMC Meeting Room, Level 2
Today’s smartphone handsets offer a wide range of functions (GPS, Bluetooth, WiFi) to customers, although are still perceived as expensive and energy consuming (requiring a daily recharge). The aim of this talk is to show how microwave measurements impact smartphones design. By optimally engineering the type of measurement made before and after design (linear, nonlinear, loadpull, modulation, and so forth), the efficiency of the design process not only increases, but tougher specifications such as smaller form factor and lower energy consumption can be met more easily. This observation is especially valid in the design of green multi-mode wireless radios, due to the delicate balance between energy efficiency and linearity (that is, cross talk between channels). The didactic level of this talk will be adapted to the background of the audience.
 
Implantable Wireless Medical Devices and Systems
Prof. J. C. Chiao, University of Texas at Arlington, USA
9 December 2013, 1130-1210 hrs @ Venus I, Level 3, Furama Riverfront Hotel Singapore
Radio frequency identification (RFID) has been utilized to increase efficiency and care quality in hospitals for patient information management, drug and equipment inventory, scheduling and staffing. To further improve healthcare, enable new diagnosis and treatment while aiming to reduce costs, major technical challenges still exist. Limited sampling and acquisition of physiological parameters during the interaction period for caregivers and patients provide incomplete information about the patients. Better care with higher diagnosis accuracy can be provided if more and time-lapsed data can be obtained without causing patients discomfort or limiting their mobility. Meanwhile, patient data documentation has become too cumbersome. The lack of portability and timely accessibility of the physiological information prevent real-time management by caregivers and/or patients themselves. Wireless technologies bring promising solutions to the aforementioned issues. Low-cost portable wireless electronics have made significant impacts to our societies. Furthermore, recent advances in micro- and nano-technologies provide unique interfacing functionalities to human tissues, and advantages such as miniaturization and low power consumption enabling novel applications in medicine and biological studies. Interfaces between biological objects and electronics allow quantitative measurement and documentation of physiological and biochemical parameters, and even behaviors. The interfaces also provide direct control or modification of cells, tissues, or organs by the electrical circuits making it possible to manage chronic diseases with a closed loop between biological objects and computers. With wireless communication, implantable devices and systems make the interfacing possible for freely behaving animals or patients without constrains, discomfort or limits in mobility. This increases the study or diagnosis accuracy in realistic environments as well as permits remote synthesis of physiological functions and delivery of therapeutic treatment. Furthermore, wireless communication enables networks for ubiquitous access to physiological information at various system levels either within one's body or within a group of patients for better deterministic and statistical understanding of issues in complex systems. The lecture focuses on the development of wireless micro devices and systems for clinical and biological applications. The systems are based on technology platforms such as wireless energy transfer for batteryless implants, miniature electrochemical sensors, nanoparticle modified surfaces, microelectromechanical system devices and microwave communication. In this talk, several implantable wireless diagnosis and therapeutic treatment systems will be discussed. An integrated wireless body network for chronic pain management has been demonstrated with wireless closed-loop integration of neurorecorders to recognize pain signals and neurostimulators to inhibit pain. Batterylessendoluminal sensing telemeter architecture has been demonstrated for an esophagus implant for remote diagnosis of gastroesophageal reflux disease (GERD), an endoscopically-implantable wireless gastro-stimulator for gastroparesis management, and a wireless bladder volume monitoring implant for urinary incontinence management. These applications enable new medicines to improve human welfare and assist better living.
 
Transparent Antennas: From 2D to 3D
Prof. Kwok Wa Leung, City University of Hong Kong
21 August 2013, 1500-1700 hrs @ Seminar Room, 8th Floor (8D-1), Temasek Laboratories, NUS
Transparent antennas are very attractive. They can be integrated with clear substrates such as window glass, or with solar cells to save surface areas of satellites. Transparent antennas are normally realized using (2D) planar structures based on the theory of patch antenna. The optical transparency can be obtained by fabricating meshed conductors or transparent conductors on an acrylic or glass substrate. Transparent designs using the meshed-conductor approach are straightforward because optical signals can pass through the opening of the meshes, while microwave signals can be transmitted or received by the conductors. The transparency and antenna property can be optimized by refining the width of the mesh. In this talk, results of a transparent antenna with meshed conductors will be presented.
In the transparent-conductor approach, transparent conductive films are used as radiators. Commonly used transparent conductive films include indium tin oxide (ITO), silver coated polyester film (AgHT), and fluorine-doped tin oxide (FTO). A sheet resistance of at least 1-2 ohm/square is required to obtain an optical transmittance of better than 70%. However, antennas made of such transparent conductor films are not efficient because of the high sheet resistance. This is one of the major obstacles to the widespread application of transparent antennas. A method that alleviates this problem will be discussed in this talk.
For a long time, transparent antennas have been of planar (2D) structures. Very recently, 3D transparent antennas have also been developed. This is a new topic. The principle of 3D transparent antenna is based on the theory of dielectric resonator antenna; the resonance is caused by the whole 3D structure rather than a confined cavity as found in the patch-antenna case. For glass, it is usually assumed that its refractive index is ~1.5, giving a dielectric constant of ~ 2.25. This value is too low for a DRA to have good polarization purity. However, it was generally overlooked that this dielectric constant was obtained at optical frequencies instead of microwave frequencies. Recently, a dielectric constant of ~7 was measured for glass at 2 GHz and this value is sufficient for obtaining a good radiator. Since crystals are basically glass, they can also be used for antenna designs. In this talk, the characteristics of glass DRAs will be shown. In addition, the idea of using a 3D glass antenna as a light cover will be presented. It has been experimentally found that the lighting and antenna parts do not affect each other because they are operating in totally different frequency regions. Interesting results will be presented in this talk.
Finally, it will be shown that 3D transparent antennas can be designed as aesthetic glass (or crystal) wares or artworks. This idea is especially useful when invisible antennas are needed due to psychological reasons. The idea has been demonstrated successfully using a glass swan and apple bought from the commercial market. The results will be presented in this talk.
 
Radio-Frequency Nanoelectronics – Bridging the Gap between Nanotechnology and R.F. Engineering Applications 
Prof. Luca Pierantoni, Università Politecnica delle Marche, Ancona, Italy
25 May 2012, 1500-1630 hrs @ L15 Seminar Room, IHPC, Fusionopolis, Connexis North Tower
In view to the new epochal scenarios that nanotechnology discloses, nanoelectronics has the potential to introduce a paradigm shift in electronic systems design similar to that of the transition from vacuum tubes to semiconductor devices. Since many nano-scale devices and materials exhibit their most interesting properties at radio-frequencies (RF), nanoelectronics provides an enormous and yet widely undiscovered opportunity for the microwave engineering community.
This lectures presents a technical overview of some of the main research fields of nanoelectronics for RF applications, i) showing the potentialities offered by emerging nano-scale materials (e.g. carbon nanotubes, graphene), ii) highlighting unprecedented microwave, millimeter-wave and THz devices and systems, iii) focusing on critical technologic aspects. While the advancement of research in this area heavily depends on the progress of manufacturing technology, still, the global modeling of multi-physics phenomena at the nanoscale is crucial to its development. Modeling, in turn, provides the appropriate basis for design.
The aim of this effort is to close the gap between the nanosciences and a new generation of highly integrated and multifunctional devices, circuits, and systems, for a broad range of applications and operating frequencies, up to the optical region. This aim can be achieved by using the panoplia of microwave engineering at our disposal.
 
Inkjet-Printed Nanotechnology-enabled RFID, IoT and "Zero-Power" Wireless Sensor Nodes
Prof. Manos M. Tentzeris, Georgia Institute of Technology, USA
21 May 2012, 1630-1800 hrs @ E4-04-02, ECE, National University of Singapore
Nanotechnology and Inkjet-printed flexible electronics and sensors fabricated on paper , plastic and other polymer substrates are introduced as a sustainable ultra-low-cost solution for the first paradigms of Internet of Things, "Smart Skins" and "Zero-Power" applications. The talk will cover examples from UHF up to the millimeter-wave frequency ranges (mmID's), while it will include the state of the art of fully-integrated wireless sensor modules on paper or flexible polymers and show the first ever 2D sensor integration with an RFID tag module on paper, as well as numerous 3D multilayer paper-based and LCP-based RF/microwave structures, that could potentially set the foundation for the truly convergent wireless sensor ad-hoc networks of the future with enhanced cognitive intelligence and "zero-power" operability through ambient energy harvesting and wireless power transfer. Examples from wearable (e.g. biomonitoring) antennas and RF modules will be reported, as well as the first integration of inkjet-printed nanotechnology-based sensors on paper and organic substrates. The talk will also present challenges for inkjet-printed high-complexity modules as well as future directions in the area of environmentally-friendly ("green") RF electronics and "smart-house" conformal sensors.
 
Commerical Application for RF MEMS
Prof. Stepan Lucyszyn, Imperial College London
23 April 2012, 1630-1800 hrs @ E5-02-32, ECE, National University of Singapore
Radio frequency micro-electro-mechanical systems (RF MEMS) have been heralded as a technology fit for the 21st century, offering unsurpassed RF performance over more conventional solid-state electronic devices. In recent years, this technology has seen a rapid rate of expansion because of its potential for advancing new products within a broad range of applications; from ubiquitous smart sensor networks to mobile handsets. Indeed, within the US, Asia and Europe, R&D is almost at fever pitch. The high levels of investment come second only to the expectations for commercial exploitation. The first RF MEMS device was reported 30 years ago by IBM. After experiencing the peak of inflated expectation in 2003 and subsequent trough of disillusionment in 2005, RF MEMS switches have emerged into the slope of enlightenment. They are now commercially available on the open market, offering new solutions for realizing high performance reconfigurable microwave circuits and systems. A major new book, entitled Advanced RF MEMS (edited by the speaker), was published by Cambridge University Press in 2010. This lecture will explain many facets of this technology and demonstrate how RF MEMS is moving out of the laboratory and into real commercial applications.