- The Wonderful World of Nonlinearity: Modeling and Characterization of RF and Microwave -
(Dr. Jose Carlos Esteves Duarte Pedro, Portugal - Bio)
Despite the many studies that have been undertaken to understand the wonderful world of nonlinearity, most undergraduate
electrical engineering programs are still confined to linear analysis and design tools. As a result, the vast majority of
microwave designers still cannot profit from the significant technological advancements that have been made in nonlinear
circuit simulation, active device modeling and new instrumentation for performance verification. So, they tend to conduct
their designs relying on experience, empirical concepts, and many trial and error iterations in the lab.
This talk will reveal the ubiquitous presence of nonlinearity in all RF and microwave circuits and the recent efforts made to understand, model, predict, and measure its diverse manifestations. We aim to bring microwave engineers’ attention to newly available techniques, and attract researchers to pursue further studies on this scientifically exciting topic.
Starting with some elementary properties of nonlinear circuits (like nonlinear signal distortion, harmonic generation, frequency conversion and spectral regrowth), we will show that nonlinearity is present in all wireless circuits, either to perform a desired signal operation or as unintentional distortion. In this way, we will show how oscillators, modulators or mixers could not exist without nonlinearity, while power-amplifier designers struggle to get rid of its distortion effects.
After this theoretical overview, we will introduce some recent advancements in nonlinear microwave circuit analysis tools and illustrate different types of models that are currently being used to represent and predict device, circuit, and system performance. Finally, we will focus the talk on the key metrics that are used to characterize nonlinear behavior, as well as newly developed lab instruments and their ability to assess device performance.
From 1985 to 1993 he was an Assistant Lecturer at University of Aveiro, and a Professor since 1993. Currently he is a Full Professor at the same University, and a Senior Research Scientist at the Institute of Telecommunications.
His main scientific interests include active device modeling and the analysis and design of various nonlinear microwave circuits, in particular, the design of highly linear multi-carrier power amplifiers and mixers. He is the leading author of Intermodulation Distortion in Microwave and Wireless Circuits (Artech House, 2003), has authored or co-authored more than 200 papers in international journals and symposia, and served the IEEE in the Portuguese MTT/AP/ED Joint Chapter, the MTT-11 Technical Committee and as a reviewer and Associate Editor for the MTT Transactions and reviewer for the MTT-IMS and the EuMC.
Prof. Pedro has served his university department as the Coordinator of the Scientific Council and as the Department Head. Prof.
Pedro received the Marconi Young Scientist Award in 1993 and the 2000 Institution of Electrical Engineers (IEE) Measurement Prize. In 2007 he was elected Fellow of the IEEE for his contributions to the nonlinear distortion analysis of microwave devices and circuits. Currently, he is an IEEE MTT-S Distinguished Microwave Lecturer.
In recent years there has been rapid changes in radio frequency (RF) and microwave techniques as well as technology.
This trend continuously enables the use of increasingly higher frequencies with their inherent advantages of smaller
components and larger bandwidth. In particular, the use of planar circuit architecture and the integration of
micro-machining technology has opened up new opportunities in terms of reduction in cost, weight, volume, power
consumption as well as the extension of operating frequencies. In keeping with the advances in technology, the
engineering design approach is also undergoing a rapid advancement by improved digital signal processing (DSP)
techniques and CAD tools. Thus the scope of RF design techniques and technology, that was confined to lower microwave
frequency bands (~10 GHz), has expanded to millimeter wave frequencies (30-300 GHz).
The talk presents different techniques and technologies for the design and development of microwave and millimeter wave integrated circuits. Starting from the conventional microstrip, other key technologies including suspended stripline, dielectric integrated guides, substrate integrated guides, PolyStrata, LTCC, CMOS and micromachining will be described. Design methodology leading to the development of several high performance components/subsystems at 35 GHz and 140 GHz is presented. The components reported are 26.5-40 GHz balanced mixer in microstrip, 18-40 GHz double balanced mixer using a novel balun structure, 140 GHz band pass filter and balanced mixer utilizing a novel suspended stripline structure, band stop filter and an oscillator utilizing a novel transition from suspended stripline to dielectric guide. Use of modern computer aided design (CAD) approach to design and develop complex microwave and millimeter wave circuits will also be discussed. The design and development of different types of micro machined circuits including antennas will then be described. The circuits will include, MEMS switches, phase shifters and filter banks. The antenna geometries considered are: circular patch antenna, square patches antenna, triangular patch antenna, and coplanar patch antennas. Finally schemes for developing reconfigurable circuits at millimeter wave frequencies using MEMS switches are presented. The talk will end by describing emerging applications of millimeter wave frequencies.
Dr. Shiban Koul
is Dr. R.P.Shenoy Astra Microwave Chair Professor and Deputy Director (Strategy and Planning) at the Indian Institute of Technology Delhi.
He is also the Chairman of Astra Microwave Products Limited, Hyderabad, a major company involved in the Development of RF and Microwave
systems in India. His research interests include: RF MEMS, High Frequency Wireless Communication, Microwave Engineering, Microwave
Passive and Active Circuits, Device modeling, Millimeter wave IC design and Reconfigurable microwave circuits including antennas.
Dr. Koul has successfully completed 34 major sponsored projects, 52 consultancy projects and 50 Technology Development Projects.
He is the author/co-author of 283 Research Papers and 7 state-of-the art books and 3 book Chapters. He holds 10 patents and 6 copyrights.
He is a Fellow of the Institution of Electrical and Electronics Engineers, USA (IEEE), Fellow of the Indian National Academy of
Engineering (INAE), Fellow of the Institution of Electronics and Telecommunication Engineers (IETE), Member of the Micro and Nano
Technology Foundation (MANCEF), USA, Member of the Indian Society of Smart Materials (ISSS), Chief Delegate for world Micro machine
Summit from India. He is the Chief Editor of IETE Journal of Research, Associate Editor of the International Journal of Microwave and
Wireless Technologies, Cambridge University Press, a member of the National Committee for URSI Commissions B, and an academic expert
member on the board of smart materials and research (B-smart). He is on the Editorial boards of the Journal of IETE and the Microwave
and Optical Technology Letters, John Wiley, USA. He had delivered more than 220 invited technical talks at various international
symposia and workshops. He is currently a serving ADCOM member and a Member of IEEE MTT society’s Technical committees on
Microwave and Millimetre Wave Integrated Circuits (MTT-6) and RF MEMS (MTT-21), Member of India Initiative team of IEEE MTT-S,
Advisor Education Committee, Membership Services Regional Co-coordinator Region-10, Vice Chair Sight Adhoc Committee MTT-S,
and MTT-S Speaker bureau lecturer. He served as a Distinguished Microwave Lecturer of IEEE MTT-S for the period 2012-2014.
Currently he is Distinguished Microwave Lecturer-Emeritus of IEEE MTT-S.
Dr Koul is recipient of Gold Medal by the Institution of Electrical and Electronics Engineers Calcutta (1977); S.K.Mitra Research Award (1986) from the IETE for the best research paper; Indian National Science Academy (INSA) Young Scientist Award (1986); International Union of Radio Science (URSI) Young Scientist Award (1987); the top Invention Award (1991) of the National Research Development Council for his contributions to the indigenous development of ferrite phase shifter technology; VASVIK Award (1994) for the development of Ka- band components and phase shifters; Ram Lal Wadhwa Gold Medal (1995) from the Institution of Electronics and Communication Engineers (IETE); Academic Excellence award (1998) from Indian Government for his pioneering contributions to phase control modules for Rajendra Radar, Shri Om Prakash Bhasin Award (2009) in the field of Electronics and Information Technology, Teaching excellence award (2012) from IIT Delhi, Award for contributions made to the growth of smart material technology (2012) by the ISSS, Bangalore, Vasvik Award (2012) for the contributions made to the area of Information, Communication Technology (ICT), M.N.Saha Memorial Award (2013) from the IETE for the best application oriented research paper and IEEE MTT Society Distinguished Educator Award (2014).