Distinguished Microwave Lecturers' Talks
Monday, 21 January 2019, 8:00am - 11:00am
Organizer: Markus Gardill, InnoSenT GmbH, Germany
Terahertz Communications at 300 GHz: Devices, Packages and System
Speaker: Ho-Jin Song, Pohang University of Science and Technology, Korea
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, packaging and potential applications.
Ho-Jin Song received the B. S. degree in electronics engineering from Kyungpook National University, Daegu, Korea in 1999, and the M.S. and Ph.D. degree in electrical engineering from Gwangju Institute of Science and Technology (GIST), Gwangju, Korea, in 2001 and 2005, respectively. Since he joined Nippon Telegraph and Telephone, Japan in 2006, which is the third largest telecommunication company in the world, he had engaged in the development of sub-millimeter and terahertz wave devices, circuits and systems for communication, remote sensing and imaging applications. In 2015, he was named to a distinguished research scientist of NTT Labs. Since 2016, Dr. Song has been with the department of Electrical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, Gyeongbuk, Korea. His current research interest includes mm-wave and terahertz circuits, antenna, packages and test-bed systems, particularly for wireless communication, connectivity and radar applications. Dr. Song was a recipient of GIST Best Thesis Award (2005), NTT Labs Research of the Year Award (2009 and 2014), Young Scientist Award of Spectroscopical Society of Japan (2010), IEEE Microwave and Wireless Component Letters Tatsuo Itoh Best Paper Award (2014) and Best Industrial Paper Award at IEEE MTTs-IMS 2016 (2016). He is a senior IEEE member and an IEEE distinguished microwave lecturer for the 2019-2021 term.
Nonresonating Modes Do It Better!
Speaker: Simone Bastioli, RS Microwave Company Inc.
The innovative concept of nonresonating modes and how this has been recently exploited to extend the performance and capabilities of the state-of-art of microwave filter technology will be presented in this talk. Although the concept is presented by mostly focusing on filters, as these are the components where this new technique has found large application over the past few years, all general features are explained and illustrated in detail thus potentially paving the way for new applications involving other passive microwave components. After a brief discussion highlighting the importance of microwave filters from a system perspective, the main concept of the talk will be introduced by defining what is a nonresonating mode and by illustrating what are the benefits of this approach. The concept is then gradually explained by using some waveguide as well as planar SIW examples, as the rectangular waveguide technology is where these modes were first observed; most importantly, these examples have been proved to considerably ease the understanding of the concepts from both students and non-experts perspectives. The general multimode environment of these structures is described step-by-step and several animations are introduced during the explanation thus really allowing the audience to absorb the more general multimode concept that otherwise often remain an obscure myth for many microwave engineers. The presentation is then extended to the most various filter technologies, such as conventional coaxial structures, dielectric resonators based architectures, as well as more original mixed technologies. The presentation will also cover few examples regarding different applications such as three-port junctions for duplexing purposes, and showing how actually some well-established four-port components have indeed always “unconsciously” exploited some form of nonresonating modes. Several manufacturing examples of actual products developed at RS Microwave (Dr Bastioli‘s affiliation) are going to be presented along this talk, thus also satisfying the more practical taste of an industry audience.
Simone Bastioli (S’10–M’11) received the Ph.D. degree in electronic engineering from the University of Perugia, Italy, in 2010.
He is the Acting Chief Engineer at RS Microwave Company Inc., Butler, NJ, United States, where he is responsible for the design and development of innovative microwave filters, multiplexers, switched filters banks, as well as more complex sub-assemblies for military applications.
Dr. Bastioli is a current IEEE Young Professional (YP), and he was the recipient of the 2012 IEEE Microwave Prize for the invention of TM dual-mode cavities and nonresonating modes. He is the vice chair of the MTT-8 Filters and Passive Components Technical Committee, and he serves as an Associate Editor of the IEEE Microwave Magazine. In 2008, he was awarded with the Best Student Paper Award (First Place) at the IEEE MTT-S International Microwave Symposium (IMS) held in Atlanta, GA, USA, and with the Young Engineers Prize at the European Microwave Conference held in Amsterdam, The Netherlands. In 2009, he was the recipient of the Hal Sobol Travel Grant presented at the IEEE MTT-S IMS held in Boston, MA, USA. He was also awarded the Young Scientist Distinction by the Polish Academy of Science at the 2014 MIKON International Conference held in Gdansk, Poland. His work resulted in several publications in international journals and conferences, as well as several patent applications.
Energy Efficient Future Wireless Communications
Speaker: Nuno Borges Carvalho, Universidade de Aveiro, Portugal
The energy needs for wireless systems is limiting the evolution of most of the IoT and 5G future solutions. In this talk an overview of the energy problem in wireless communication systems will be presented, either from a mobile network point of view, but also from a IoT point of view. The main objective is to discuss future wireless paradigms that will be changing soon with 5G and beyond, those include the spread of a distributed mobile network by using Cloud Radio Access Networks, with its associated Software Defined Radio approaches, but also the issue of battery-less wireless devices, combining wireless power transmission and backscatter communications. The talk starts first with a general overview of the energy needs for a future XG networks, and then presents in an integrated way both approaches of C-RAN and IoT wireless design. The presentation will cover topics like the hardware part of the SDR and design of battery-less wireless sensors networks. Issues like characterization of mixed-signal devices, designing of C-RAN SDR approaches, design of passive backscatter sensors will be discussed, according to the audience.
Nuno Borges Carvalho was born in Luanda, Angola, in 1972.
He is currently a Full Professor and a Senior Research Scientist with the Institute of Telecommunications, University of Aveiro. and an IEEE Fellow.
He coauthored Intermodulation in Microwave and Wireless Circuits (Artech House, 2003), Microwave and Wireless Measurement Techniques (Cambridge University Press, 2013) and White Space Communication Technologies (Cambridge University Press, 2014).
He is associate editor of the IEEE Transactions on Microwave Theory and Techniques, IEEE Microwave Magazine, Cambridge Wireless Power Transfer Journal and IET Microwaves, Antennas and Propagation Journal.
He is the co-inventor of four patents. His main research interests include software-defined radio front-ends, wireless power transmission, nonlinear distortion analysis in microwave/wireless circuits and systems, and measurement of nonlinear phenomena. He has recently been involved in the design of dedicated radios and systems for newly emerging wireless technologies.
Dr. Borges Carvalho was the co-chair of the IEEE MTT-20 Technical Committee and the past-chair of the IEEE Portuguese Section. He is also the chair of the URSI-Portugal Metrology Group.
Everything You Can Do With Vector Nonlinear Microwave Measurements
Speaker: Patrick Roblin, Ohio State University, USA
The advent of nonlinear vector network analyzers (NVNA) has stimulated the introduction of new paradigms in microwave engineering for (1) the measurement, (2) the modeling and (3) the design of nonlinear microwave circuits such as microwave power amplifiers and oscillators.
This talk will start with a review of vector large-signal microwave measurements for the acquisition of the phases and amplitudes of the multi-harmonic incident and reflected waves at the ports of a nonlinear device. The various types of NVNA architecture available, the procedure used to calibrate them and the calibration traceability will be presented.
Next the behavioral models used for the representation of the measured multi-tone multi-harmonic data will be reviewed. This will include the general multi-harmonic Volterra functions for CW periodic nonlinear RF excitations, the X-parameter/S-function approximations for mildly nonlinear RF excitations and their extension for modulated multi-harmonic signals.
Circuit-based nonlinear microwave models can also be directly extracted from large-signal measurements for a targeted range of operation. Examples of SOS-MOSFET and GaN models extracted and verified using a few real-time active load pull (RTALP) measurements will be presented. The efficient phase sweeping of the RTALP drastically reduces the number of large-signal measurements needed for the model development and verification while maintaining the same intrinsic voltage coverage as in conventional passive or active load–pull systems. The bias dependence of the charges and device IV characteristics can then be simultaneously extracted from these large-signal RF measurements using artificial neural networks (ANN).
NVNA’s also find application in the design of power amplifiers (PA). To optimize the power efficiency of PAs, specific internal modes of operation are usually targeted at the device current source reference planes as estimated using nonlinear deembedding. However given the tremendous large search space for the multi-harmonic terminations for waveform engineering, it is beneficial to first use a nonlinear embedding device model to predict from the desired internal mode of operation, the required amplitude and phase of the multi-harmonic incident waves at the transistor measurement reference planes. The verification of the resulting amplifier power efficiency optimization can then be performed using NVNA measurements. Examples of such design for Doherty and Chireix amplifiers will be presented.
Finally in addition to CW signals, pulsed or modulated signals can also be measured by NVNAs. This is particularly important for nonlinear devices such SOS-MOSFET or GaN HEMTs which are affected by various low-frequency memory effects such as parasitic bipolar junction transistor effects, self-heating, and cyclostationary charging of traps. Recent techniques reported for low-duty rate pulsed and modulated RF NVNA measurements will then be reviewed to shine new light in the time-varying response of transistors excited by high peak to average power ratio (PAPR) modulated signals.
Patrick Roblin was born in Paris, France, in September 1958. He received the Maîtrise de Physique degree from the L' Université Louis Pasteur, Strasbourg, France, in 1980, and the D.Sc. degree in electrical engineering from Washington University, St. Louis, MO, in 1984. In 1984, he joined the Department of Electrical and Computer Engineering at The Ohio State University (OSU), Columbus, OH where he is currently a Professor. His present research interests include the measurement, modeling, design and linearization of non-linear RF devices and circuits such as power-amplifiers, oscillators and modulators. He authored and co-authored two textbooks published by Cambridge University Press. He is the founder of the Non-Linear RF research lab at OSU. He has developed at OSU two educational RF/microwave laboratories and associated curriculum for training both undergraduate and graduate students. He is currently serving as a distinguished microwave lecturer for IEEE MTT.