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This paper presents the design of a large Gigahertz Transverse Electromagnetic (GTEM) cell for Electrical/Electronic Sub-Assembly (ESA) testing of a car or other information technology (IT) equipment as well as the challenges of its design and fabrication. The 7.5 meter long and 4 meter width and 4 meter height dimensions of this cell are large enough to test ESAs inside. The operating frequency band is from 30 MHz to 6 GHz based on CISPR standards. To increase the operating frequency of the GTEM and to improve the uniformity of the wave, hybrid absorbers are mounted at the end wall. These absorbers consist of ferrite tile and pyramid absorbers, which have large bandwidth and high performance. The dimensions of the GTEM cell are too large and therefore full wave simulation is difficult and time consuming. In this paper, we have introduced a two-step method to convert a pyramidal absorber into a one-layer flat absorber. This technique simplifies our GTEM cell full wave simulation. On the fabrication side, the effect of distortion of a long metal sheet on the performance of the room are numerically examined. Finally, the acceptable measurement results of the GTEM are reported.

The 28th IEEE Workshop on Signal and Power Integrity (SPI) was held from May 12 to 15, 2024, in Lisbon (Portugal), a historic city situated in one of the oldest countries of Europe. The workshop was technically co-sponsored by the IEEE EMC Society. For nearly three decades, this workshop has been serving as a premier platform of repute for exchanging the ideas and dissemination of knowledge amongst the researchers working in the area of Signal/Power Integrity. Held annually in Europe at the onset of summer, the workshop comprehensively covers all aspects related to Signal/Power Integrity. In this column, a recap of the workshop held in Lisbon is presented. In addition to that, the paper which received the best paper award is also published in this column. The paper is focused on the IC buffer modeling based on the channel response using a machine learning technique. I hope our readers will enjoy reading this column!

Imagining a specific SPICE model for the Cable Discharge Event (CDE) is impossible because the model depends on the cable length, material, and type. This paper aims to propose an instruction to extract a SPICE model for Flat Ribbon Cables (FRCs), which have a wide range of applications in electronics. This work introduces general information and considerations about the CDE in FRCs, and the conductor of the FRC considers a transmission line which to Extract its equivalent circuit; a technique based on S-Parameter measurement and transmission line theory is demonstrated. Also, this work regards the mutual capacitance between the conductor of FRC in the extracted SPICE model. In this work, the analytical technique and the 3D full-wave software synergize with each other to increase the reliability of the proposed SPICE model. This work evaluates the effect of cable length and termination resistance on the discharge waveform. The proposed instruction can be expanded to the other cables. It helps the designers observe the CDE impacts besides other transient events on their circuits and systems without spending much time and expense.

To improve the reliability of radio electronic devices, engineers use redundancy of the most relevant circuits. The simplest and most common solution is classical cold redundancy in which the primary and redundant circuits are located far from each other. Meanwhile, locating the primary and redundant circuits close together makes it possible to use modal distortions to protect both circuits from unwanted ultra-wideband interference. This approach is known as modal redundancy or modal reservation (MR). This paper presents the results of signal integrity analysis for a structure with single MR before and after failures. It is shown that the bandwidth after failures changes. This affects the rate of data that can be excited to the input of the device without significant distortion of the useful signal. The authors used pseudorandom binary sequences with a data rate of 50 and 200 Mbps. It is experimentally shown that failures in the redundant circuit do not significantly degrade the quality of signal integrity in the bandwidth. Thus, the data-dependent jitter changes from 12 (before failures) to 19 ps (after the worst failure). In all investigated variants, the eye stays open; as a result, the bit error rate will be low. The mismatch of the redundant circuit has the largest effect on the noise amplitude. As a result, the signal-to-noise ratio decreases from 57 (before failures) to 28 (after the worst failure). To confirm the measurements, we performed electrodynamic simulations. Their results are in good agreement with the experimental data.

This paper elaborates the near-field scanning and modeling technique developed for electromagnetic interference (EMI) analysis. The technique has been increasingly deployed in many R&D labs of universities and testing centers of industry companies due to its advantages in terms of time and cost, comparing with conventional EMI measurement methods. The major research works related to the near-field scanning and modeling are probe design and source reconstruction method (SRM). In this article, the working principle of electric and magnetic probes are firstly introduced. Probe parameters including calibration factor, electric center, sensitivity, spatial resolution and bandwidth are discussed. Next, the equivalent radiation source modeling approach is presented. Through SRM, a complex and unknown EMI source is substituted with the simplified equivalent radiation source based on the electromagnetic fields measured by magnetic and/or electric probes. The phaseless SRM is thereafter discussed for addressing the limitations in conventional SRM and its applications prove that the near-field scanning and modeling technique can effectively predict EMI far-field radiation and near-field coupling.

The paper analyzes ultrashort pulse (USP) decomposition in the meander microstrip line (MSL) turns when the distance (sn) between the non-core turns changes, both separately and simultaneously. It was found that the decrease in sn strengthens the distortion effect on the line output voltage waveform and decreases its amplitude. The results of N-norm analysis demonstrate that the reduction of sn decreases the probabilities of electrical breakdown, arc discharge, and component burnout. At the same time, due to total pulse energy, the probability of dielectric breakdown does not change, and the probability of component damage increases. The maximum attenuation of the USP at the output of the folded turn was 4.95 times. The results obtained in different software products show an acceptable agreement. The signal integrity was analyzed using a pseudo-random binary sequence source (PRBS) of 10.000 bits and bitrates of 50 Mbit/s and 100 Mbit/s. The effect of sn on the useful signal integrity is demonstrated. It is shown that at 50 Mbit/s some characteristics are improved. Based on the useful signal integrity analysis, it was pro-posed to use a folded turn with a phase locked oscillator PLL1707. It was also proposed to use the folded turn together with a gas-dis-charge device to improve the protective characteristics.

Electromagnetic compatibility (EMC) for integrated circuits is becoming more and more important over the recent years. With the increasing number of functionalities and applications microcontrollers-based systems require higher level of immunity than ever before. This article focuses on one of the most important EMC test for industrial application, the Electrical Fast Transient (EFT) or Fast Transient Burst (FTB) defined by the IEC 61000-4-4 standard. The goal of this paper is to give key elements to understand the FTB stress propagation in a microcontroller system and its consequences. The resonances of the power distribution network are presented as being the key element to understand and improve the robustness of a microcontroller against fast transient stresses. A modeling and measurement method of the power distribution network is detailed to predict the resonances of the system and it is explained through the presentation of three different test cases.

Anticipating the arrival of high-frequency era, the author has been promoting the development of new technology to complement the communication systems from early stages. In this paper, an overview of “Code Sensing Communication System”, which is one of the new communication systems, is introduced. The “Code Sensing Communication System” is, “a system that reads the code being displayed, compares it with the setting contents of the computer memory on the receiving side, and expresses the corresponding information by image and sound.” The necessity of this research is in the point that as the communication frequency becomes higher, the electromagnetic wave diffraction and reflection phenomena that have been contributed to conventional communication will not inevitably become applicable. Also, from the EMC point of view, it has the significance of solving problems such as mutual interference and malfunction of electronic devices in a communication environment where many frequencies are mixed, and to realize non-inductive communication.

Owing to the greater integration capability, flexible multilayer foil (FMLF) technique has a great potential to promote the evolution of passive integration techniques. To understand the mechanism of this technique is essential for its applications and popularization. To this end, this paper reveals the fundamentals and terminal configuration principles to realize various functional electromagnetic integration units with FMLF technique. A regular FMLF winding is taken as the research object, from theoretical analyses on the associated distributed electromagnetic component (DEMC) circuits, the lumped electromagnetic component (LEMC) circuits with different terminal configuration modes are derived. Moreover, A FMLF winding prototype is built for experimental verifications. The LEMC circuits are demonstrated through the comparative analyses between practically measured and LTspice based simulated impedances or port characteristics.

Machine learning (ML) is one of today's most studied subjects in almost every research area. It provides interesting mathematical tools that could inspire us to rethink about the EMC/SI/PI engineering. This paper gives a preliminary review on machine learning methods for EMC/SI/PI technology developments. Sample examples from publications on EMC/SI/PI methodologies powered by machine learning methods are discussed. There are three major types of machine learning methods. From an EMC/SI/PI engineering point of view, supervised learning provides heterogeneous high dimensional surrogate blackbox model, unsupervised learning enables dimension reduction for physics recovery, and reinforcement learning uses rule-based decision making for optimizations. It is important to select proper machine learning tools and algorithms for various EMC/SI/PI tasks.

We present a thin planar pixelated frequency selective surface (FSS) based absorber engineered to achieve near unity absorption over a wide bandwidth. The absorber design for unity absorption in a planar configuration is highly challenging because it requires a crucial trade-off between bandwidth, thickness, and absorption level. We demonstrate a simple design strategy adopted to fulfill such steep constraints simultaneously. The unit cell consists of a simple FSS layer inkjet printed over a paper substrate, attached to a grounded foam substrate. We have achieved a wideband absorption of more than 99.999% by reducing the reflection level below −50 dB from 12.17 to 13.33 GHz for normally incident plane waves. The absorber also maintains the −10 dB bandwidth from 8.51 to 18.85 GHz. The absorber offers −10, −20, −30, −40, and −50 dB fractional bandwidths of 75.6%, 43.57%, 25.1%, 14.65%, and 9.1% respectively. The proposed absorber is suitable for conformal shield packaging.

Airborne Geophysical surveys include the exploration of mineral reserves by sub-surface conductivity measurement using Time Domain Electromagnetic Methods (TDEM). Transmitter-receiver coil assembly is suspended from the helicopter and the power required for energizing the transmitter and other paraphernalia is driven from the Helicopter. The pulsating high ramp rate currents in the Transmitter coils generate Electric fields in the sub-surface. These electric fields cause eddy current which depends on the electrical conductivity of the sub-surface. These eddy currents generate a secondary magnetic field that decays as a function of the electrical conductivity of the medium. The decay of the secondary magnetic field is measured by the secondary coil and processed by front-end electronics. The inverse problem is solved to estimate the nature of mineral reserves. The depth of penetration of magnetic fields generated by the transmitter coil is proportional to the cube of magnetic dipole moment of transmitter coil. The peak current in the coil thus becomes an important performance parameter. The electrical parameters of the optimized coil design require a minimum 48 Volts DC supply at the input. The power available from the Helicopter is limited to 28 V, 100 A which does not suffice the requirements of peak current. The up-conversion from 28 V to 48 V/96 V is carried out using a DC-DC converter. For meeting the statutory requirements of the airworthy clearance agency, the DC-DC converter is required to be MIL-STD-461E compliant. This paper describes the design of EMI compliant system which qualified conducted emissions (CE) and radiated emissions (RE) tests. Filter design, partition box design, and time-staggering of switching of resonant-type chopper concepts are detailed along with results of EMC qualifications.

The conducted emission test is one of the important EMC tests in the frequency range of 10 kHz–30 MHz for commercial and military equipment. AMNs are required in order to perform measurements and AMN impedance contributes to measurement uncertainty to some extent. Although AMN impedance is defined in terms of magnitude and phase and its effects are studied in commercial standards, most standards such as military standards only define the magnitude and give no information about the uncertainty contribution. In this paper, firstly we developed a software solution to calculate the theoretical nominal AMN impedance values for a given AMN circuit and calculated the corresponding uncertainty contribution by using the magnitude and phase information in accordance with CISPR 16-4-2. Following this, we instructively studied a variety of widely used AMN types and performed their uncertainty analysis. Finally, we focused particularly on military tests and the uncertainty contribution of the defined military AMNs to military conducted emission tests where phase information is not defined.

The purpose of the "SPOTLIGHT" column is to highlight the top downloaded papers for the Transactions on Electromagnetic Compatibility and Electromagnetic Compatibility Magazine, pre-selected based on the statistics of the IEEE Xplore digital library (http://ieeexplore.ieee.org), by presenting their corresponding abstracts. A balance of the top downloaded paper abstracts is published quarterly, giving to the technical and scientific community the opportunity of being informed about the contributions of a wide range of EMC topics, their authors and affiliations, and making the EMC field better known.

The MIL-STD-461 CS101 test is one of the essential low-frequency conducted immunity tests for military and aerospace equipment, however it includes some challenges in application. The major challenge is the necessity for the measurement of injected CS101 ripples under the power frequency of the EUT. The measurement of CS101 ripples on the power frequency is almost impossible without taking some extra precautions. In addition to the hard necessity of measuring the CS101 ripple voltage induced across the EUT power input, the other challenge of measuring the ripple voltage that drops across the power source side under the AC power frequency of the EUT is now required by MIL-STD-461G, which aggravates the severe CS101 test conditions of AC devices. In this paper, we propose a FFT-based time domain solution and a method to instantly check the ripple voltage that drops across the power source side, in other words across the 10 μF test capacitor, during the test under the AC EUT power frequency and to verify that it is low enough and not affecting the reliability of the test. The method proposed in this paper significantly overcomes the CS101 test challenges and makes CS101 test results more accurate. In this paper, we also extensively focused on effective solutions to reduce the ripple voltage induced across the power source side along with measurement uncertainty analysis.

I am very excited about this issue of the EMC Magazine since we are introducing the newly updated Signal Integrity and Power Integrity column. As you will see on page 33, we have a new Associate Editor, Jai Narayan Tripathi with the Indian Institute of Technology Jodhpur located in the beautiful and historic area of Jodhpur, Rajasthan, India. Dr. Tripathi responded to a “Call for Associate Editor” notice we advertised in a past issue of the EMC Magazine. Having editorial experience with other IEEE publications and connections with our Sister Societies MTI-S and AP-S (Microwave Theory and Technology Society as well as Antennas and Propagation Society), we welcome him to our Magazine Staff. You can learn more about Dr. Tripathi in the introduction to the Signal Integrity and Power Integrity column on page 33. You will also learn about his vision for the column – what types of papers are a “good fit”, and how the column will complement the papers in the new IEEE Transactions on Signal and Power Integrity soon to be published by the IEEE EMC Society.

The purpose of the "SPOTLIGHT" column is to highlight the top downloaded papers for the Transactions on Electromagnetic Compatibility and Electromagnetic Compatibility Magazine, pre-selected based on the statistics of the IEEE Xplore digital library (http://ieeexplore.ieee.org), by presenting their corresponding abstracts. A balance of the top downloaded paper abstracts is published quarterly, giving to the technical and scientific community the opportunity of being informed about the contributions of a wide range of EMC topics, their authors and affiliations, and making the EMC field better known.

This paper presents a comprehensive Inter Laboratory Comparison (ILC) of conducted emission measurements as per CISPR 22. The proposed ILC, an important requirement of International Standard ISO/IEC 17025 as part of Quality Assurance is accomplished by utilizing Comparison Noise Emitter (CNE III) source (150 kHz–30 MHz) which is widely used for ILC measurements of EMC Tests facilities. The ILC for five NABL (National Accreditation Board for Testing and Calibration Laboratories) accredited EMC laboratories in India is presented. The measurements data are presented in peak and average detection modes over the frequency range of interest under controlled environment. The measured emission is in the range of 65 dBμV to 80 dBμV. Z-score is calculated for all the laboratories over 0.165 MHz–30MHz range using Classical Method as well as Robust Method. The measurements at all 5 EMC laboratories exhibited a Z-score ≤ 2. This paper intends to report that the performance evaluation of participant Laboratories can be done using either by Classical Method or Robust method. A comparative analysis is presented for all the measured data for both Classical and Robust methods.

Vulnerability assessment of electronic devices excited by various transient electromagnetic disturbances (TEDs) has been a key issue in electromagnetic susceptibility research. This paper proposes a generalized vulnerability assessment method that includes acquiring data and building assessment model. The data is normally acquired by carrying out experiments, while the assessment model is mainly determined by prior information. As different devices under test (DUTs) could offer a different amount of prior information, a generalized assessment model consisting of a white-box model, a grey-box model, and a black-box model is built to deal with situations of sufficient prior information, partial prior information, and no prior information, respectively.

We're taking a deep dive into the archives (well, I found this under a pile of papers at the late, great Leonard Thomas' house a few years back). It is the summer version of “The Washington Bulletin,” published by the Institute of Radio Engineers (IRE), which was a professional organization that existed from 1912 until December 31, 1962. On January 1, 1963, it merged with the American Institute of Electrical Engineers (AIEE) to form the Institute of Electrical and Electronics Engineers (IEEE). (Thanks Wikipedia.)

The aim of the paper is to investigate the performance in terms of immunity of different grounding solutions of shielded cables such as coaxial, twinax and triaxial (doubled screened), by simple SPICE simulations. The cables are modeled by lumped equivalent circuits based on the key parameter of transfer impedance. It is shown that, cascading N electrically short unit cells of the cable, it is possible to obtain the same accurate results of a distributed model, valid without limit in frequency, for the frequency range of interest. The advantage of this approach is that these circuit models are suitable for both frequency and transient simulations. They can be easily implemented in the latest generation of commercial SPICE-like simulators with minimum effort, and the simulations run in very few seconds. The accuracy of the models is validated by comparison with measurements, with the results obtained by a full-wave 3D software and other methods. Some practical grounding cable structures are simulated and guidelines are given.

In high-speed VLSI systems, decoupling capacitors are the key components to minimize power supply noise in power delivery networks. For efficiently maintaining power integrity in these systems, optimal selection and placement of decoupling capacitors is necessary. This paper presents a computational intelligence based generic framework to solve the industrial problem of decoupling capacitor optimization in a practical power delivery network using metaheuristic algorithms. The cumulative impedance of a power delivery network is minimized below the target impedance by optimal selection and placement of decoupling capacitors using the state-of-the-art metaheuristic algorithms. A comparative analysis of the performance of these algorithms is presented with the insights of practical implementation.

Electromagnetic interference (EMI) instrumentation has significantly evolved over the last thirty years. In this paper, the classical architecture of a conventional receiver is described and compared with the newest architecture of a Fast-Fourier-transform (FFT) based receiver. Additionally, different ways to measure the modal emissions, that is, the common and differential modes, with both types of receivers are described. In a conventional receiver, modal emissions can be measured using an external noise separator. In a dual-port FFT-based receiver, this can be done in the digital domain. Both receivers have been used to measure a device under test emitting non-stationary interference.

Welcome back to Chapter Chatter! I hope everyone had a nice summer break and for those of you lucky enough to make it to our symposium in Spokane, Washington, it was great seeing you there! It had been three years since we had an in-person IEEE International EMC+SIPI Symposium so there was a ton of catching up to do with our fellow EMC Society members. It was also nice seeing a new generation of EMC engineers attend and hearing it was their first symposium! Hopefully, it will not be their last. Make sure to see the Call for Papers next year's symposium in Grand Rapids, Michigan, and plan to attend. See the symposium ad on pages 70–72.

The 2x-thru, the most common standard used for creating fixture models, is never identical to the Fixture-DUT-Fixture due to printed circuit board (PCB) process variation. This difference leads to de-embedding error in the frequency and time domain. This paper introduces a method of impedance corrected de-embedding and its associated advantages. Impedance corrected de-embedding removes the error from differences between the Fixture-DUT-Fixture and reference 2x-thru impedance by implementing a peeling process. Further, the method is inherently more robust, because the fixture manufacturing tolerances do not impact the de-embedding results.

This paper presents a study on the Polynomial Chaos based approach for uncertainty quantification. It discusses employing different polynomial chaos based techniques for uncertainty quantification of RF circuits. Here, the performance of different Stochastic Collocation techniques such as the pseudo-spectral projection, linear regression, and interpolation technique, is investigated using two illustrative circuit examples. The first example deals with the uncertainty quantification of phase noise in a 2.4 GHz CMOS LC tank oscillator, while in the second one, gain of a 2.4 GHz low-noise amplifier is analyzed in the presence of uncertainty. The applied techniques are investigated and compared with the traditional Monte Carlo simulations approach. The advantages and disadvantages of each of the presented techniques are discussed, which are validated using the illustrations. The results of our study provide guidance for choosing the appropriate technique for modeling and quantifying uncertainty for similar circuits.

5G technology can enable novel healthcare applications and augment existing medical device use of wireless technology to improve healthcare delivery. Having the dual role of medical device and cellular user equipment (UE), 5G-enabled devices navigate a plethora of rules and tests before they can operate on a 5G network to deliver their intended medical function. In this paper, we review the state-of-the-art of 5G UE certification programs and testing specifications. We then identify test challenges and discuss the relevance of existing test practices to support the 5G-enabled medical device safety and effectiveness. This information is useful to medical device developers planning to incorporate 5G technology in their products and wireless engineers working to expand mobile services into the healthcare vertical.

The 28th IEEE Workshop on Signal and Power Integrity (SPI 2024) was held from May 12 to 15, 2024, in Lisbon, Portugal. The IEEE EMC Society was a Technical Co-Sponsor of the event. Bringing together 87 participants from 19 countries spread throughout three continents, the SPI 2024 technical program included 24 oral and 11 poster presentations, for a total of 35 papers presented and now published in the IEEE Xplore® Digital Library.

In this paper, different techniques and measures are described and discussed that are effective to reduce risks related to electromagnetic disturbances in mission- or safety-critical systems. The aim of these techniques and measures is to make a system EMI-resilient or fault-tolerant with respect to EMI. Whenever a fault occurs within the system, the techniques and measures should either allow that the system continues to work in a safe manner (possibly with reduced performance) or trigger that the system is switched to a safe-state. The techniques and measures align with the well-proven techniques and measures described in IEC 61508, the main standard in the field of Functional Safety. It is described how they have to be modified or optimized to be effective for EMI. At the end of the paper, the use of inversion and spatial diversity is studied in more detail, thereby giving guidance on possible pitfalls.

The purpose of the “SPOTLIGHT” column is to highlight the top downloaded papers for the Transactions on Electromagnetic Compatibility and Electromagnetic Compatibility Magazine, pre-selected based on the statistics of the IEEE Xplore digital library (http://ieeexplore.ieee.org), by presenting their corresponding abstracts. A balance of the top downloaded paper abstracts is published quarterly, giving to the technical and scientific community the opportunity of being informed about the contributions of a wide range of EMC topics, their authors and affiliations, and making the EMC field better known.

Hello! We are pleased to bring you the 3rd Quarter 2017 issue of the IEEE EMC Magazine. We have a sneak peek of some activity at the 2017 IEEE International Symposium on EMC, Signal and Power Integrity (EMC+SIPI) held in Washington, DC over August 7-11. Chair Mike Violette and his committee organized an outstanding symposium. You can read about some of the symposium activity in the President’s Message, Chapter Chatter (Chicago’s summary), EMC Standards Activities, iNARTE Informer, and the Board of Directors Activities columns. Note in the Signal Integrity column, Associate Editor Jun Fan has brought us the winner of the Best SIPI Paper Award presented at this year's symposium. Titled, “A Novel Z-Directed Embedded Component for the Reduction of Voltage Ripple on the Power Distribution Network for PCBs”, the paper is by a team of highly regarded authors from the EMC Laboratory at the Missouri University of Science and Technology and Lexmark. You can find it starting on page 91.

Validation of a computational electromagnetic (CEM) model is a critical issue in electromagnetic simulation applications. By appealing to the representative academic website "IEEE Xplore", we collected the literature on CEM validation ranging from 1985 to 2014. Mainstream publications, leading research agencies and core authors are explored with statistical analysis on the collected literature. This information is useful for the beginner to follow the most influential research work on CEM validation. Visual analysis is further conducted for investigating the research power distributions across countries/regions. Results show that the USA and Italy are the most prolific regions, with respect to either highly cited papers or leading research agencies. Finally, specific attention is paid on investigating research collaboration in CEM validation, due to its interdisciplinary nature. The most productive co-research group is identified. It contributes 11.3% of the total papers and 20.5% of the total citations with only 2.7% of the total authors, showing clearly the importance of collaborative research in this field.

The Boer War in South Africa (1899-1902) was the first occasion in which wireless communications were used in a military conflict. This paper traces the history from the point of view of both the British and the Boer forces: both of whom had intentions to use this latest invention on the field of battle. Marconi's apparatus, in its most elementary form, went with the British Army to the front, but failed. The Boer's German equipment was captured and never saw service. The Army soon rejected wireless but the Royal Navy acquired the apparatus and made it work. No doubt circumstances and personalities played their part but by far the major factor in determining success and failure was the natural electromagnetic environment. All these components of a fascinating saga are discussed in this paper.

EMC design using only numerical simulations remains out of reach. There are at least three main hurdles to overcome, i) the impossible description of all physical parameters involved; ii) their intrinsic uncertainty and / or the endless exploration of their combined variations if controlled by design; iii) the unavailability of some models such as susceptibility models. Therefore, performing parametric studies based on available models does not provide neither an efficient analysis nor a complete picture of the governing features of an EMC scenario. How to prevent and quantify situations at risk remains an open question. In this paper, we examine an EMC scenario as a standard source / victim interaction under a probabilistic approach based on available models. As far as the ‘victim’ is concerned, without access to any susceptibility model, statistical inference based on a limited set of experiments provides a relevant probabilistic information. Then, we suppose that the source and path of interactions are described through numerical simulations involving a complex combination of multiple parameters (intrinsically uncertain or adjustable by design). In this frame, we highlight the interest of statistical inference, learning techniques and specific tools dedicated to extreme events exploration. More precisely, we present the combination of kriging, which provides metamodels (i.e. surrogate models) with negligible cost of calculation, and sensitivity analysis for EMC design parameters. Overall, these statistical tools (and others) offer many new perspectives for conventional EMC software packages.

The 27th 2023 IEEE Workshop on Signal and Power Integrity (SPI) was held from May 7 to May 10, 2023, in the Portuguese city of Aveiro. This workshop was technically co-sponsored by IEEE EMC Society. Over two and a half decades, this workshop has been a premier platform for the SI/PI researchers around the globe. The workshop is held every year in Europe at the start of summer and as the name suggests, it covers all the aspects related to Signal/Power Integrity. In this column, the report of the workshop held in Aveiro is presented. Followed by the report, you will find a ‘Call for Papers' for the IEEE Transactions on Signal and Power Integrity (T-SPI) which is also a publication of IEEE EMC Society. As stated in this column in the last issue of the EMC Magazine, the scope of this column has been widened and therefore it is more generic and thus differs from the IEEE T-SPI. This column is open for submissions including a very wide range of articles such as Tutorials, Review Papers, Invited Articles, Research Papers, Comments, Perspectives, Failure Case Studies, Letter to the Associate Editor, etc. For prospective articles to this column, submissions are welcome through the proper channel. For any queries/suggestions/comments, you may write to me at jai@iitj.ac.in.

The purpose of the “SPOTLIGHT” column is to highlight the top downloaded papers for the Transactions on Electromagnetic Compatibility and Electromagnetic Compatibility Magazine, pre-selected based on the statistics of the IEEE Xplore digital library (http://ieeexplore.ieee.org), by presenting their corresponding abstracts. A balance of the top downloaded paper abstracts is published quarterly, giving to the technical and scientific community the opportunity of being informed about the contributions of a wide range of EMC topics, their authors and affiliations, and making the EMC field better known.

In this paper we discuss electrically thin absorbers: thin lossy layers which can fully absorb (convert to heat) energy of electromagnetic waves falling on the layer's surface. Most often, thin absorbers are used as covers of metal bodies, and the goal is to eliminate reflections from conducting surfaces, with applications in EMC and stealth technology. However, in some applications it is necessary to absorb power in free-standing thin layers, for example, to create optically transparent windows which can fully absorb microwave radiation in a given frequency range. The goal of this paper is to explain the fundamental operational principles of thin absorbers, discuss fundamental limitations on their performance, and give a brief overview of recent research on thin absorbers for the microwave frequency range and EMC applications.

Wireless charging is an attractive option of energy replenishment for electric vehicles (EVs) as it does not require direct electrical contact to the EVs. However, the radiated magnetic field from the EV wireless charging system can be an electromagnetic compatibility (EMC) concern nearby electrical and electronic devices. This paper investigates the influence of the power level, the clearance, and offset between coils on the radiated magnetic field emitted from the wireless charging system. The experimental study shows that these variable parameters can affect the radiated magnetic field level and the field distribution, which provides valuable input for standardization of the test setup and working condition of the EV wireless charging system.

As the requirements characterizing simulation studies of realistic configurations constantly become more demanding, it is not uncommon that several contemporary electromagnetic problems need to be investigated within a stochastic, rather than a fully deterministic, framework. In this paper, we revise the basic aspects of Polynomial Chaos (PC) methodologies, which currently play a prominent role in the research field of uncertainty quantification. PC techniques enable the representation of the quantities-of-interest (Qol) via polynomial expansions, which facilitate the computation of all the pertinent necessary information, including statistical moments, distributions, and sensitivity indices. As the construction of approximate models with optimal efficiency is always desirable (so that a given level of accuracy is ensured with minimum computational effort), we also pay attention to the development of anisotropic PC

This paper introduces a new model for estimation of the fundamental frequency as well as power harmonics components using extended and linear Kalman filters. It also compares the proposed method with existing techniques including a commercial power harmonic measuring device compatible to IEC 61000-4-7 standard in an experimental setting. The proposed method is shown to result in significantly enhanced estimation of the fundamental frequency and slightly improved harmonic estimation.

This paper presents an automatic procedure for the optimization of the hyperparameters of a delay rational model approximating the frequency-domain behavior of highspeed interconnects. The proposed model is built via a kernel-based regression, such as the Least-Square Support Vector Machine (LS-SVM), by considering an ad-hoc kernel with two hyperparameters related to the propagation delays introduced by the system. Such hyperparameters, along with the Tikhonov regularizer used by the LS-SVM regression, are carefully tuned via an automatic approach based on a k-fold cross-validation and Bayesian optimization. The feasibility of the effectiveness of the proposed modeling approach are investigated on a high-speed link.

Various popular methods for Uncertainty Quantification (UQ) rely on the computation of Polynomial-Chaos (PC) expansions, which represent stochastic processes via convergent polynomial series. The computational cost for determining the expansion coefficients in such methods is related to the number of input variables, and is significantly enlarged in high-dimensional problems. On the other hand, the PC coefficients of the basis functions can be considered, in many cases, to form a sparse vector. This property is exploited in this paper to build PC models that are accurate and computationally efficient, by implementing the Orthogonal Matching Pursuit (OMP) as the solver, which can deal with underdetermined linear systems, assuming that their solution is sparse. In order to enhance the computational efficiency even further, the presented PC method is applied adaptively for various PC model orders, and the best solution is chosen according to a leave-one-out criterion. Finally, an optimally-designed multilayer electromagnetic filter for EMC applications is examined, considering ten or twenty stochastic design variables.

Recently, machine learning (ML) techniques have gained widespread diffusion, since they have been successfully applied in several research fields. This paper investigates the effectiveness of advanced ML regressions in two EMC applications. Specifically, support vector machine, least-squares support vector machine and Gaussian process regressions are adopted to construct accurate and fast-to-evaluate surrogate models able to predict the output variable of interest as a function of the system parameters. The resulting surrogates, built from a limited set of training samples, can be suitably adopted for both uncertainty quantification and optimization purposes. The accuracy and the key features of each of the considered machine learning techniques are investigated by comparing their predictions with the ones provided by either circuital simulations or measurements.

Congratulations to Co-Chairs Alistair Duffy and Bruce Archambeault as well as the organizing committee for the 2021 Joint IEEE International Symposium on Electromagnetic Compatibility, Signal & Power Integrity, and EMC Europe. Held virtually from July 26 - August 20, the symposium featured an extensive technical program and exhibition. More than 1,000 attendees appreciated the high number of quality papers and record number of workshops and tutorials. The exhibition offered a wide variety of products and services provided by leading companies in the electromagnetic compatibility and signal/power integrity (EMC+SIPI) community. It was a great month for EMC+SIPI education and shopping!

It's Chapter Chatter time! I trust everyone had a chance to check out this year's annual IEEE Symposium on EMC+SIPI that recently wrapped up; I hope that by 2022 we can all meet again in person in Spokane, Washington (August 1-5, 2022)! Please see the call for papers on page 77 and plan your contribution to the technical program.

Estimating the quality ($Q$) factor of an unloaded reverberation chamber (RC) is a challenging problem in practice. To answer this question conservatively and confidently, this paper reviews the measured unloaded $Q$ factors of 38 RCs worldwide. The effective wall conductivities are summarized from the reported measurement results. Broadband $Q$ factors of RCs from the same supplier but with different dimensions are highlighted to compare. The measurement results show that the effective wall conductivity is frequency dependent and the dependency behaves in a similar way. The empirical values of the effective wall conductivity are extracted to estimate the unloaded $Q$ factors conservatively.

Communication-based train control (CBTC) systems are aimed at providing control and signaling for rail transportation. These operate in environments that include tunnel and open-air sections, as well as busy stations, coexisting with Wi-Fi and cellular communication networks. Modeling electromagnetic compatibility and interference (EMC/EMI) issues in CBTC is most efficiently achieved by hybridizing several computational electromagnetic techniques rather than relying on a single one. This paper presents an overview of the applicable standards and some typical EMI scenarios for CBTC systems. Then, we discuss recent advances in hybridizing the vector parabolic equation (VPE) method, ray-tracing (RT) and the finite-difference time-domain (FDTD) technique, towards the efficient modeling of such scenarios.

5G small-cell base stations are featured by having massive electronics and signal processing hardware for the purpose of digital beamforming. This paper deals with important components within such 5G base stations which are the Board-to-Board (BtB) RF connectors that connect such electronic boards within the base station. It is attempted to introduce a simple and cost-effective simulation and measurement technique for determining shielding effectiveness (SE) in the near-field based on the IEC-61967-3 standard. A 16-channel BtB 5G system is investigated in the sub-6 GHz band as a real-scenario where the obtained results were proven to be highly accurate as compared to simulations.

The paper deals with satisfying the quasi-stationarity (or quasi-static) condition in studies of impulse quantities. The validity of the definition of voltage, current, and immittance is discussed. Examples are given regarding the electromagnetic compatibility issues when the quasi-stationarity condition is not met, thus the basic electric circuit quantities are not uniquely defined.