19th SBMO – Brazilian Symposium of Microwave and Optoelectronics and the 14th CBMag – Brazilian Congress of Electromagnetism


More resilient emergency communications: the effects of fire on radio coverage

Prof. Rafael F. S. Caldeirinha, FIET, SMIEEE and SMURSI

Following the forest fires that devastated most of the Portuguese forest landscape in 2017, coupled to the emergency communications system recovery failures, this keynote addresses the current research work on radio wave propagation phenomena in rural areas, particularly under wildfire environments. The most recent developments on the development of a simulation framework to enhance the quality, performance and the resilience of the emergency radio communication systems during a wildfire event, will be presented. To this extent, on-going research work includes several numerical and experimental studies that contribute for the better understanding of the propagation effects on radio signals under fire environments. Initial measurement results from a detailed measurement campaign carried out at the Laboratory for Forest Fire Studies from Association for the Development of Industrial Aerodynamics (ADAI), University of Coimbra, clearly demonstrate the generation of air ionization (plasma) due to the combustion process, yielding significant excess loss in real wildfire scenarios. This is of particular importance in the development of a radio propagation tool to obtain coverage maps based on relevant models for propagation in rural areas, particularly in highly dense forest areas, taking into account the topography and the obstruction in the radio path and the integration of fire models. The development of a comprehensive radio coverage tool will allow the identification of radio exclusion zones in real time as the fire front develops, being essential for ground forces in decision making. This builds up on more than 23 years of research work on attenuation in vegetation media, in which prediction models contributed to ITU-R 833-9 recommendation.

Rafael F. S. Caldeirinha (AMIET’98 SMIEEE’00 SMIEEE’15 FIET’15 SMURSI’19) was born in Leiria, Portugal, in 1974. He received the BEng (Hons) degree in Electronic and Communication Engineering from the University of Glamorgan, UK, in 1997. In 2001, he was awarded a Ph.D in Radiowave Propagation by the same University for his research work in vegetation studies at frequencies from 1 to 62.4 GHz. He received the Agregado (Habilitation) academic title in 03/2020 by the University of Aveiro (Portugal), for this contribution to radiowave propagation in vegetation media. He is currently Head of the Antennas & Propagation (A&P-Lr) research group at Instituto de Telecomunicações, Leiria, Portugal, and Coordinator Professor in Mobile Communications at the School of Technology and Management (ESTG) of the Polytechnic Institute of Leiria (IPLeiria), Portugal.

His research interests include studies of radiowave propagation through vegetation media, including wildfires, radio channel sounding and modeling and frequency selective surfaces, for applications at micro- and millimeter-wave frequencies. Prof. Caldeirinha has authored or co-authored more than 170 papers in conferences and international journals and 4 contributions to ITU-R Study Group, which formed the basis of the ITU–R P.833–5 (2005) recommendation.

He is Associate Editor of the IEEE Transactions on Antennas and Propagation journal; Associate Editor of the IET on Microwaves, Antennas and Propagation journal; Member of the editorial board of the International Journal of Communication Systems, IJCS (New York, Wiley); Program chair of WINSYS International Conference between 2006 and 2012; Appointed Officer for Awards and Recognitions of the IEEE Portugal section in 2014; Chair of the IEEE Portugal Joint Chapter on Antennas & Propagation – Electron Devices – Microwave Theory & Techniques since 2016; Regional Delegate of European Association for Antennas and Propagation (EurAAP) for Andorra, Portugal and Spain since March, 2017; and a Senior Member of IEEE and URSI and Fellow Member of IET.

Fotônica para 5G

Marcelo E. V. Segatto

A quinta geração de telefonia móvel deverá unir um grande conjunto de tecnologias aumentando, de forma significativa, a quantidade de dados que trafega nas redes. Nessa palestra iremos discutir como a fotônica e, em especial, as comunicações ópticas estão ajudando nesse grande salto tecnológico. Quais os desafios e soluções possíveis e quais os avanços tecnológicos ainda são necessários.

Graduado em Engenharia Elétrica pela Universidade Federal do Espírito Santo (1991), mestrado em Engenharia Elétrica/Comunicações pela Universidade Estadual de Campinas (1994) e doutorado em Física – Imperial College of Science Technology and Medicine (2001). Trabalhou como pesquisador na British Telecom e, posteriormente, na Corning Research Centre (CRC) entre os anos de 1998 e 2001. Fez um estágio pós-doutoral no INESC-Porto em Portugal, em 2007. Desenvolve pesquisas em parceria com diversas empresas nacionais e internacionais e com diversos grupos de pesquisa noBrasil e no exterior nas áreas de telecomunicações, projeto e análise de desempenho de redes ópticas de acesso e de transporte, sistemas e dispositivos para comunicações ópticas, comunicações por rede elétricas de baixa e média tensões e, mais recentemente, em redes de sensores sem fios e sensores em fibras ópticas. Atualmente, é professor Titular do Departamento de Engenharia Elétrica Universidade Federal do Espírito Santo. É membro Sênior da OSA – The OpticalSociety, e membro de diversas sociedades científicas no Brasil e no exterior. Coordena ou coordenou diversos projetos de pesquisa, desenvolvimento tecnológico e inovação. É membro do conselho técnico-científico da Fundação de Amparo à Pesquisa e Inovação do Espírito Santo, jáparticipou de vários comitês técnico-científicos da CAPES e CNPq. Atua nos projeto de Internacionalização da UFES. Tem experiência na área de Engenharia Elétrica, com ênfase em Sistemas de Telecomunicações, atuando principalmente nos seguintes temas:telecomunicações, comunicações ópticas, redes ópticas, eletromagnetismo aplicado, edispositivos ópticos. Desde o início da pandemia do Novo Corona Vírus, coordenadiversas ações na área tecnológica para a mitigação dos efeitos do COVID19.

Modelling of high temperature superconducting large-scale systems

Frederic Trillaud

The modeling of the electromagnetic behavior of High Temperature superconductors have evolved from analytical formulae to numerical models based on Finite Element (FE) Analysis. These numerical models have allowed addressing more complex problems over the past few decades. The latest numerical developments rely on a new mixed formulation of the Maxwell’s equations referred to as T-A formulation. This new formulation combined with different techniques to lower the computation burden (time and resources), i.e., homogenization, multi-scaling combined with interpolation techniques allows to achieve “real-time” simulation on a personal computer at a fair accuracy. On a 2D planar case study made of commercial second generation high temperature superconductors which present a large aspect ratio between its width and thickness (factor > 1000), it is showed that, in addition to an accurate computation of the losses, it is possible to obtain a good representation of the local current density distribution inside individual tape. The ability to reproduce the local current density distribution affects directly the quality of the magnetic field which, in turns, contributes to improve the estimation of the losses. For completeness, the proposed formulation and techniques were compared to classical approaches. Subsequently, they were used to model an actual magnet, the 32 T all-superconducting magnet (axisymmetric case) commissioned at the National High Magnetic Field laboratory, in Florida, USA. These new techniques be readily used to tackle any large-scale systems based on 2G HTS wires and in particular the modeling of superconducting power systems as well.

Keywords: Current density distribution, dynamic losses, homogenization, iterative multi-scale, T-A formulation.

Dr. Frederic Trillaud graduated in electrical engineering from the French engineering school, École Spéciale des Travaux Publics (ESTP), in 1999. He received a master’s degree in electrical engineering in 2000 from the University of Orsay, France, and his PhD in September 2005 on the “Study of the thermo-electronic stability of LTS conductors and contribution to the study of the thermoelectric stability of HTS conductors” from The Grenoble Institute of Technology (INP), France. Part of the PhD program, he visited from 2001 to 2003, the National High Magnetic Field Laboratory (NHMFL) in Tallahassee, FL, USA, as a research scholar. From 2005 to 2007, he was appointed post-doctoral associate at the Massachusetts Institute of Technology (MIT) to develop in collaboration with American Superconductor Corporation (AMSC) detection and protection systems for superconducting magnets. From 2007 to 2010, he was hired as mechanical engineer at the Ernesto Lawrence Berkeley National Laboratory (LBL) working on cryogenic systems, mechanical characterizations of superconducting cables and wires, development of data acquisition systems and electromagnet design. Since 2011, he has been working with the Institute of Engineering of the National Autonomous University of Mexico (UNAM) to develop superconducting power systems in a tenure track position. In 2013, he was appointed lecturer at the graduate school of Engineering. In June 2019, he was rewarded the position of professor at the Institute of Engineering of the UNAM. His main topics of research are the multi-physics modelling of large-scale superconducting systems for aplications in science and power engineering systems.

A link to the institutional webpage:

Advances in Superconducting Magnets Technology

Marco Breschi

This presentation gives an overview of the main applications of superconducting materials to Magnet Technology. The key role of superconducting magnets and magnet systems in the development of modern particle accelerators for high energy physics (HEP) and controlled thermonuclear fusion machines is described. In both cases, significant advances in the magnet technology might be obtained by the substitution of low temperature superconducting (LTS) materials with high temperature superconducting (HTS) materials. The advantages and drawbacks of HTS based electromagnets with respect to their LTS counterparts are addressed. Recent developments in the application of superconducting magnets to Magnetic Resonance Imaging (MRI) for medical purposes and to the realization of very intense magnetic fields for scientific research are described. The design and manufacturing of superconducting magnets require dealing with multi-physics and multi-scale phenomena of remarkable complexity. Some of the challenges to be faced when dealing with electromagnetic, thermal and mechanical issues are described, showing the technical solutions adopted in the magnet realization. The perspectives of application of the superconducting magnet technology in future international projects are finally addressed.

Marco Breschi graduated with honors in electrical engineering from the University of Bologna, Italy, in July 1997. He received his Ph.D. in Electrical Engineering from the University of Bologna in March 2001, with a study on the electrodynamics of superconducting magnets for the Large Hadron Collider of CERN. In 2004 he worked as a visiting scientist at the National High Magnetic Field Laboratory, Florida, USA. Since October 2001 he is Assistant Professor, and since October 2014 he is Associate Professor at the Department of Electrical, Electronic and Information Engineering of the University of Bologna. His research activity is related to various aspects of magnet technology, applied superconductivity and the numerical computation of electromagnetic fields. He is the author or co-author of several multiphysics models for superconducting wires, cables and magnets, based either on FEM or circuit models, developed to investigate the electromagnetic, electrothermal, and electromechanical phenomena of interest for technical applications. From 2007 to 2017 he was an independent member of the Working Group SULTAN of ITER (International Thermonuclear Experimental Reactor) and coordinated several research projects for the analysis of the ITER cable in Conduit Conductors performance. He served the scientific community as a member of the Scientific Program Committee of the International Conference on Magnet Technology (MT22, MT23), the European Conference on Applied Superconductivity (EUCAS 2015), the HTS Modeling Workshop (in 2016 and 2018). From 2013 to 2015 he served as a Chairman of the IOC of the CHATS-AS Workshop on numerical modeling of superconducting devices. Since 2015 he is the Chairman of the IOC of the ‘International School on Modeling for Applied Superconductivity’ (first edition in Lausanne, Switzerland, in 2016, second edition in Caparica, Portugal, in 2018). In 2019 he was appointed Co-Chairman of the European Conference on Applied Superconductivity to be held in Bologna, Italy, in 2023.

Implementações de ondas milimétricas em 5G e novas bandas

Bruno Duarte

Com a explosão de estudos e implementações nas faixas de ondas milimétricas, discursaremos sobre formas de teste e medição, assim como padrões já atuais na indústria e academia. Abordaremos, também, as aplicações práticas em bandas próximas e além dos 100 GHz.

Bruno Duarte é engenheiro de aplicações de RF na Keysight Technologies. Graduado em Engenharia Elétrica com ênfase em Telecomunicações pela Escola Politécnica da USP e especialista em Tecnologias e Sistemas de Informação pela UFABC. Atuou nas empresas Rede Globo, Agilent Technologies e Telefonica Global Solutions, sendo hoje responsável pelas soluções de RF, microondas e medidores de impedância na Keysight.


© MOMAG 2020 – 19º SBMO e 14º CBMag