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This study was conducted to derive a quality factor for the evaluation of an enclosure with a metallic wire mesh. The electrical characteristics of the metal mesh surface can be determined through equivalent surface impedance conversion; thus, an enclosure was manufactured after analyzing the scattering parameters of the metallic wire mesh surface. The quality factor of the enclosure can be derived simply by measuring a single standard antenna bonded by 1-port. To verify the effectiveness of the 1-port time domain quality factor derivation method, a numerical simulation was performed using the Finite Integration Technique (FIT) of commercially available software CST Microwave Studio. The verified quality-factor derivation method was applied to an enclosure with a metallic wire mesh surface. A quality factor measurement experiment was performed for the case in which one side of the enclosure was in the opening surface, one side of the enclosure was a metallic wire mesh surface, and all the surfaces of the enclosure were closed with metal. Based on the measurements, the quality factor in the case of Open was the lowest at 26.82 dB, followed by 32.24 dB for the case of Mesh and 32.51 dB for the case of Closed. [ABSTRACT FROM AUTHOR]

Satellites experience a variety of electromagnetic environments, from launch to orbital operation, making it is necessary to verify that satellites can properly operate in these environments. Currently, many satellites. such as optical satellites, radar satellites, communication satellites, and navigation satellites. are being developed in Korea, and based on this development trend, electromagnetic environment verification technology for satellite systems is becoming increasingly important. In this study, we describe a method for verifying the electromagnetic environment at the satellite system level. The purpose, requirements, methods, and considerations of each item are introduced for the EMC test, RF auto-compatibility test, LV RF compatibility test, and electrostatic discharge analysis. It is expected that the proposed method for verifying the electromagnetic environment at the satellite system level can be used in the verification of satellites under development in Korea. [ABSTRACT FROM AUTHOR]

Improving interface connectivity of magnetic nanoparticles in carbon aerogels is crucial, yet challenging for assembling lightweight, elastic, high‐performance, and multifunctional carbon architectures. Here, an in situ growth strategy to achieve high dispersion of metal–organic frameworks (MOFs)‐anchored cellulose nanofibrils to enhance the interface connection quality is proposed. Followed by a facile freeze‐casting and carbonization treatment, sustainable biomimetic porous carbon aerogels with highly dispersed and closely connected MOF‐derived magnetic nano‐capsules are fabricated. Thanks to the tight interface bonding of nano‐capsule microstructure, these aerogels showcase remarkable mechanical robustness and flexibility, tunable electrical conductivity and magnetization intensity, and excellent electromagnetic wave absorption performance. Achieving a reflection loss of −70.8 dB and a broadened effective absorption bandwidth of 6.0 GHz at a filling fraction of merely 2.2 wt.%, leading to a specific reflection loss of −1450 dB mm−1, surpassing all carbon‐based aerogel absorbers so far reported. Meanwhile, the aerogel manifests high magnetic sensing sensibility and excellent thermal insulation. This work provides an extendable in situ growth strategy for synthesizing MOF‐modified cellulose nanofibril structures, thereby promoting the development of high‐value‐added multifunctional magnetic carbon aerogels for applications in electromagnetic compatibility and protection, thermal management, diversified sensing, Internet of Things devices, and aerospace. [ABSTRACT FROM AUTHOR]

The rapid development of miniaturized, high-frequency, and highly integrated microelectronic devices has brought about critical issues in electromagnetic compatibility and thermal management. In recent years, there has been significant interest in lightweight polymer-based composites that offer both electromagnetic interference (EMI) shielding and thermal conductivity. One promising approach involves constructing three-dimensional (3D) interconnection networks using functional fillers in the polymer matrix. These networks have been proven effective in enhancing the thermal and electrical conductivity of the composites. This mini-review focuses on the preparation and properties of 3D network-reinforced polymer composites, specifically those incorporating metal, carbon, ceramic, and hybrid networks. By comparing the effects of different filler types and distribution on the composite materials, the advantages of 3D interconnected conductive networks in polymer composites are highlighted. Additionally, this review addresses the challenges faced in the field of multifunctional thermal management and electromagnetic protection materials and provides insights into future development trends and application prospects of 3D structured composites. [ABSTRACT FROM AUTHOR]

With the system interconnection and intelligence of application scenario equipment, the electromagnetic environment of chips is becoming more and more complex. Problems such as communication interruption and data loss caused by electromagnetic interference often occur. The electromagnetic reliability of chips has become an important index to measure their availability. In order to effectively detect the electromagnetic reliability of industrial chips applied to specific scenarios, it is necessary to measure and analyze the electromagnetic characteristics of the application scenarios, as the boundary conditions of the electromagnetic protection simulation analysis and design of the chip, and to develop Electromagnetic Compatibility (EMC) test items, test limits and test methods suitable for carrying out tests and monitoring on chips. The paper presents an acquisition system, which can complete the collection of transient electromagnetic interference, steady electromagnetic field, temperature, humidity and near-field data. The transient interference measurement frequency range is 300 kHz–500 MHz, with a rising edge of 1.5 ns; the steady-state electromagnetic field measurement frequency ranges from 100 Hz to 3 GHz. By collecting the electromagnetic environmental characteristics of chips and analyzing situations in which chips are prone to interference, protective measures can be implemented. [ABSTRACT FROM AUTHOR]

The trends of miniaturization, lightweight, and high integration in electronics have brought serious issues in heat dissipation and electromagnetic compatibility and also limited the simultaneous use of thermally conductive and microwave absorption materials. Therefore, it is imperative to design materials that possess those dual functions. In this work, one‐pot method is used to anchor zeolitic imidazolate framework ZIF‐67 coated with polydopamine (PDA) on boron nitride (BN) to obtain BN@ZIF‐67@PDA. The pyrolysis product BN@Co‐C@C is used as heterostructured thermally conductive/microwave absorption fillers and blended with polyethylene terephthalate (PET) to prepare BN@Co‐C@C/PET composites. When the mass ratio of BN to ZIF‐67@PDA is 7.5:1 and the mass fraction of BN7.5@Co‐C@C is 45 wt%, the BN7.5@Co‐C@C/PET composites exhibit excellent thermal conductivities and microwave absorption performances. The thermal conductivity coefficient is 5.37 W m−1 K−1, which is 35.8 times higher than that of PET (0.15 W m−1 K−1), and also higher than that of 45 wt% (BN7.5/Co‐C@C)/PET composites (4.03 W m−1 K−1) prepared by directly mixing. The minimum reflection loss of 45 wt% BN7.5@Co‐C@C/PET composites are −63.1 dB at 4.72 GHz, and the corresponding effective absorption bandwidth is 1.28 GHz (4.08–5.36 GHz), achieving excellent microwave absorption performance at C band. [ABSTRACT FROM AUTHOR]

In this article, a new differential magnetic‐field probe with high detection sensitivity for near‐field scanning is proposed. The proposed probe consists of a U‐shaped differential loop as a driven element, a pair of asymmetric inverted U‐shaped differential loops as a parasitic element, two transmission line, two connected vias, two shorted vias, and two output ports. Connected and shorted vias are used to form the sensing structure with high sensitivity. Some shield vias are used to reject the unwanted electric–field coupling. The proposed probe is simulated, fabricated, and measured to demonstrate the design rationality. The measured results reveal that the presented probe has a higher detection sensitivity and a high electric‐field suppression ratio greater than −35 dB in the range of 0.01 to 20 GHz. [ABSTRACT FROM AUTHOR]

Electromagnetic Interference and Compatibility (EMI–EMC) are a serious problem in Microelectromechanical Systems (MEMS), and specially in powered by wireless energy transfer MEMS. Most MEMS have dimensions in the order of 1 mm or less, thus, most of the suitable electromagnetic radiation sources have wavelengths larger than this, making isolation of electromagnetic effects very difficult. Model‐Based Systems Engineering (MBSE) can be an excellent tool to deal with EMI—EMC in MEMS during early design phases. In this work, we present a problem‐solving procedure and integration of EMI—EMC in MEMS from a Model‐Based Systems Engineering perspective. This approach is described in detail by a real example using a procedure based on nine steps fully integrated with the proposed systems engineering methodology. For example, the use of context diagrams (IBDs) and N SQUARE charts to describe EMC interactions is explained in detail. The system is formed by a Wireless Power Transfer (WPT) subsystem working near 2.45 or 4.5 GHz coupled to an electromagnetic micromotor. This micromotor contains copper microcoils which can receive electromagnetic radiation directly at the same time that the WPT subsystem. The greatest difficulty is, then, to power the WPT while isolating the micromotor, and optimizing the coupling interface. A summary of the most important EMC concepts and tools are reviewed from the systems engineer perspective and possible problems during the design and testing phases are discussed in detail using the example. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Chongqing University of Technology (Natural Science) is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction. Most electromagnetic compatibility studies carried out in the context of power switch research are generally valid for low frequencies. This frequency restriction appears to be too restrictive for a complete analysis of the electromagnetic interference conducted. The novelty of this work lies in the load-dependent an optimal selection of IGBTs and MOSFETs for least-disturbance power switching in the frequency range from 150 kHz to 30 MHz, based on an optimal experimental selection procedure and show the impact of load value on switch switching and noise generation. Purpose. Analysis of the fundamental possibility of selecting a switching device with a power supply based on an experimental measurement which allows to increase the reliability of the entire mechanism operation and significantly simplify the design. Methods. In this paper, the proposed study is used and compared with experimental results at low and high frequencies. Then, a comparison is made for conducted electromagnetic interference (common-mode and differential-mode) generated by IGBT and MOSFET for different loads, and the proposed methodology is verified on an experiment suitable for predicting terminal overvoltage analysis and conducted electromagnetic interference problems. Practical value. The primary method for establishing a conducted electromagnetic interference source for switching devices is based on IGBT and a MOSFET depending on the resistive load. [ABSTRACT FROM AUTHOR]

During circuit conduction immunity simulation assessments, the existing black-box modeling methods for chips generally involve the use of time-domain-based modeling methods or ICIM-CI binary decision models, which can provide approximate immunity assessments but require a high number of tests to be performed when carrying out broadband immunity assessments, as well as having a long modeling time and demonstrating poor reproducibility and insufficient accuracy in capturing the complex electromagnetic response in the frequency domain. To address these issues, in this paper, we propose a novel frequency-domain broadband model (Sensi-Freq-Model) of IC conduction susceptibility that accurately quantifies the conduction immunity of components in the frequency domain and builds a model of the IC based on the quantized data. The method provides high fitting accuracy in the frequency domain, which significantly improves the accuracy of circuit broadband design. The generated model retains as much information within the frequency-domain broadband as possible and reduces the need to rebuild the model under changing electromagnetic environments, thereby enhancing the portability and repeatability of the model. The ability to reduce the modeling time of the chip greatly improves modeling efficiency and circuit design. The results of this study show that the "Sensi-Freq-Model" reduces the broadband modeling time by about 90% compared to the traditional ICIM-CI method and improves the normalized mean square error (NMSE) by 18.5 dB. [ABSTRACT FROM AUTHOR]

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

At present, the traditional passive filter in on-board charger(OBC) has poor low-frequency performance, an active feedback loop was added to the traditional on-board charger passive filter, a design method of on-board charger electromagnetic interference(EMI)hybrid filter based on current sensing and current injection (CSCI)was proposed, and the structure, analysis and feedback loop design process of on-board charger hybrid filter were given. The experimental results show that compared with the existing on-board charger passive filter scheme, the new EMI filter scheme proposed has greatly improved the results of conduction test and radiation test. [ABSTRACT FROM AUTHOR]

In order to further improve the defect detection capability of gas insulated switchgear and avoid equipment faults, broadband current array sensing system is designed to simultaneously monitor the system status such as partial discharge, relative dielectric loss, and power frequency overvoltage. The dynamic model of the system is analysed, and based on which, the system state equation is obtained meanwhile fault observer is designed, and the system stability criterion under H∞ condition is calculated. The reliability of the system under different packet loss rates is verified based on cloud models, and the principle of using appropriate electromagnetic compatibility to prevent packet loss rates below 50% is proposed. [ABSTRACT FROM AUTHOR]

This letter delves into the influence of drain wire design on electromagnetic radiated emission (RE) from a commercial universal serial bus (USB) cable operating in a high‐speed data transfer mode. The investigation involves an experimental comparison of measured RE across various retrofitted cables. Notably, it is demonstrated that the distribution of contact points on the drain‐shield has negligible effects on RE. Conversely, relocating the drain wire externally to the shields and minimizing the distance with respect to the grounding connector leads to a significant reduction in RE, particularly within the sub‐MHz frequency range. Consequently, regulatory proposals are put forth to diminish overall RE and enhance the RE compliance of USB cables. [ABSTRACT FROM AUTHOR]

Measurement of lightning current plays a critical role in the field of atmospheric electricity. Traditionally, Rogowski coils or low-resistance shunts were employed for measuring lightning currents in the range from several amperes up to several hundreds of kilo-amperes, and high-value resistors were utilized for measuring corona discharge currents at sub-ampere levels. However, these approaches were not suitable for continuously recording the vast range of lightning currents. For this sake, we have developed a lightning current measurement system equipped with a shock-tolerant low-noise amplifier module. With the system installed on a tall tower, sub-ampere level currents just before the lightning initiation were observed for the first time. To confirm the authenticity of the recorded currents, the background noise of the measurement system and surrounding environment were identified, and a digital multi-frequency notch filter was proposed for de-noising. Results show that the system can achieve a current identification level of 50 mA even in complex electromagnetic environments, while having a measurement capability of 220 kA. [ABSTRACT FROM AUTHOR]

Ever‐increasing bandwidth requirements from various industries drive the need for the ever‐increasing bandwidth of antennas used for testing. Broadband Double‐Ridged Guide Horn (DRGH) antennas are used extensively in antenna measurement and ElectroMagnetic Compatibility/Interference (EMC/I) testing. The current state‐of‐the‐art broadband DRGH antennas reported in the literature for use in measurement applications cover bandwidth ratios as large as 36:1 (0.5–18 GHz). This paper presents the design and realisation of a DRGH antenna with a 100:1 bandwidth ratio (0.5–50 GHz). To achieve such a wide bandwidth, the ridge gap, width and feed were optimised, and a novel coaxial‐to‐ridge waveguide launcher section based on a typical Vivaldi antenna was developed. Backward radiation was reduced using an absorber‐filled cavity. A prototype DRGH antenna was manufactured using additive manufacturing, also referred to as 3D printing. Simulated and measured results obtained in an anechoic chamber are presented. [ABSTRACT FROM AUTHOR]

This research presents a comprehensive investigation into the electromagnetic compatibility (EMC) analysis of rail vehicle speed sensors. It begins by establishing rigorous EMC testing standards for radio field speed sensors used in railway vehicles, encompassing parameters such as antenna orientation, interference strength, frequency range, and signal stability. Additionally, the study explores the theoretical underpinnings of radio frequency (RF) emissions, emphasizing the importance of loop size in PCBs with transmission lines and the complexities involved in estimating field strength. Notably, the research introduces the integration of quantum-based 3D reconstruction algorithms into EMC analysis, enabling a more accurate representation of the electromagnetic environment surrounding rail vehicles. Furthermore, an optimization algorithm based on chaos theory and neural networks is proposed, offering a promising approach to fine-tune sensor design for enhanced EMC compliance. Through experiments and tests, the study demonstrates the significant impact of optimization and quantum-enhanced 3D reconstruction on the EMC of rail vehicle speed sensors, resulting in reduced RF radiation and improved electromagnetic compatibility. This research contributes to the advancement of EMC analysis in the railway industry, ensuring the safety and performance of critical components. [ABSTRACT FROM AUTHOR]

In this paper, a design scheme for a dual‐band waveform‐selective metasurface absorber (MSA) is presented based on the combination of two metal resonator structures loaded with nonlinear circuits. Dual‐band MSAs with four different configurations are constructed by loading capacitor/inductor‐based nonlinear circuits into the gaps of two square‐patch (SP) and two square‐ring (SR) resonators, all of which can achieve selective absorption of short pulses and continuous waves (CWs) at two frequencies independently. As a typical example, the dual‐band MSA with the SP resonator loaded with the inductor‐based nonlinear circuit and the SR resonator loaded with the capacitor‐based nonlinear circuit is systematically studied. First, the selective absorption performance of the dual‐band MSA for CWs and pulses under different input powers is demonstrated. Second, the selective absorption properties of the dual‐band MSA for pulses with different pulse widths are studied. Third, the waveform‐selective absorption characteristics of the dual‐band MSA for oblique TE and TM waves are also illustrated. Finally, the influence of circuit component parameters on the selective absorption properties of pulses and CWs is systematically studied. The proposed dual‐band MSAs have potential application areas such as antenna design, wireless communications, and electromagnetic compatibility. [ABSTRACT FROM AUTHOR]

Compared with electromagnetic compatibility (EMC) testing in anechoic rooms, open-area EMC testing takes advantage of in situ and engine running status measurement but suffers from non-negligible external electromagnetic interference. This paper proposes a novel environmental interference suppression method (named the EMC environmental interference suppression algorithm ( E 2 I S A )) that separates signals from backgrounds via image segmentation and recognizes the near–far site signal via a group of time-varying features based on the difference in the near-site EM radiative characteristic. We find that the proposed E 2 I S A method, which combines the deep learning segmentation network with the classical recognition methods, is able to suppress environmental interference signals accurately. The experiment results show that the accuracy of E 2 I S A reaches up to 95% in the face of VHF (Very High Frequency) EMC testing tasks. [ABSTRACT FROM AUTHOR]

Backgrounds: As rotating machines become more complex and their operation accuracy improves, limitations imposed on unbalanced vibration of the rotor are becoming stricter. The traditional approach to unbalanced vibration is offline dynamic balancing, which is very costly. Purposes: In this paper, we design and propose an electromechanical automatic balancing system based on a rigid single rotor with a single plane and constant rotational speed. The system includes actuators, vibration counting equipment, and control algorithms, and it can monitor and balance rotor unbalance vibration in real time while the equipment is operating. Compared to other balancing actuator types, the proposed design has a larger counterweight and improved electromagnetic compatibility; as such, it can provide the stepless counterweight adjustment. Methods: Through the independent design and construction of electromechanical balancing head actuator as well as the developed supporting drive control algorithm and super balancing capability processing algorithm, fast and accurate identification and target suppression of rotor vibration is achieved, and the control algorithm is programmed using a programmable logic controller (PLC), which effectively removes the dependence on computer equipment. Results: Simulation and experimental validation of the algorithm have shown that the electromechanical automatic balancing actuator has a vibration reduction capability of 18um at 600 rpm for the propeller single rotor system. Conclusions: The electro-mechanical automatic balancing head can achieve a larger proportion of counterweight and a greater balancing capacity with the same total weight. In addition, the automatic balancing system has better electromagnetic compatibility, realizes stepless adjustment of counterweight mass, and the control algorithm makes the unbalanced vibration of the rotor in the balancing process continuously monotonically decrease, which ensures the efficient and precise stability of the balancing process. [ABSTRACT FROM AUTHOR]

The paper proposes an approach to predicting the electromagnetic resistance of an unmanned aerial vehicle (UAV) when exposed to an electrostatic discharge. The approach is based on the study of the electromagnetic environment and electromagnetic interference in the interface communication lines of the UAV onboard equipment. The effect of a discharge of static electricity from an engine blade on a UAV fuselage made of a composite material is considered. From the results of the study of the electromagnetic environment in the intra-fuselage space, it can be seen that the strength of the electromagnetic field at the calculation points reaches sufficiently large values, therefore, the electromagnetic compatibility of the UAV onboard equipment may deteriorate. The predicted levels of electromagnetic interference in the interface communication lines will also lead to a malfunction of the onboard equipment of the UAV. Technical measures are proposed that will ensure the electromagnetic stability of the UAV when exposed to a discharge of static electricity.

Abstract Instead of using expensive highly performing conventional pyramidal absorbers, in some cases, the use of absorbers based on very cheap eco‐friendly materials is an attractive alternative. The authors introduce a novel technique to improve the absorption bandwidth of these intrinsically low‐quality absorbers by adding a Salisbury screen at the base of the pyramidal absorber, which adds two extra design parameters. The first is the resistive sheet surface impedance, and the second is the resonance frequency of the Salisbury screen. By tuning these two parameters, better impedance matching can be obtained. This is verified with the help of a transmission line model, full‐wave simulations, and measurements. The method is applied to two different lower‐quality absorbers found in the literature. In the first absorber, the operating bandwidth is increased at the lower frequency side by 40%, and in the second one, this is about 90%. Finally, a prototype of an eco‐friendly combined absorber is designed and fabricated. The measurement validates the expected behaviour.

This paper presents an exact series solution for fields radiated from a magnetic-frill source that is valid everywhere above the plane of the magnetic-frill. The derivation of the field expressions is based on Lommel expansions and direct integration of the vector potential. The field expressions presented in this study were in excellent agreement with the corresponding fields available in the literature. The known expressions for fields radiated from the magnetic-frill on its axis and those radiated from magnetic current rings are obtained as special cases from the field expressions presented in this study. These expressions can be used to accurately compute the tangential component of the incident electric field on the surface of an antenna needed in the MoM solution for a thick as well as a thin antenna input impedance computation, in addition to the analysis of the characteristics of coaxial wave-guides, cables, antennas mounted on ground planes, and in the analysis of electromagnetic compatibility problems and assistance in estimating human exposure to radiation from the apertures of coaxial cables.

Undesired conversion between common-mode (CM) and differential-mode (DM) noise often occurs in modern electronic and electrical systems, posing challenges in terms of Electromagnetic Compatibility (EMC). Modal analysis represents a crucial tool in EMC investigation and provides insight into the mechanism underlying mode conversion. By inspecting CM and DM behaviors and their interconversion, it allows for understanding of conducted emission propagation mechanisms, drives electromagnetic interference (EMI) filter design towards optimal/tailored solutions, and enables the possibility to identify the main contributors to the radiated emission phenomenon. This paper offers a comprehensive review of mathematical methodologies and modelling strategies for EMC-oriented modal analysis, with particular emphasis on mode conversion phenomena. To this end, modal decomposition techniques and standard parameters for quantifying mode conversion are summarized and compared. Additionally, the paper provides an overview and in-depth discussion of different scenarios and test cases in which mode conversion occurs, with the final goal to achieve a systematic comprehension of its root causes and consequences within power and communication systems. Eventually, a survey of circuit modelling approaches for mode conversion is presented, offering insights into addressing this phenomenon effectively.

The standard CISPR 16-1-1 defines the measuring receiver using a black-box approach and sets requirements for its accuracy and spectral properties. Traditionally, such test receivers were developed using a superheterodyne architecture. Recently, time-domain electromagnetic emission measurement systems have been built employing direct sampling instruments, mainly oscilloscopes, and relying on specific signal processing to emulate the performance of compliant instruments. In these cases, the short-time Fourier transform is used for spectral estimation, but the corresponding electromagnetic compatibility standards lack details for its correct use with respect to parameters such as windowing function, overlapping factor, and frequency interpolation. Moreover, it is unclear which combination of spectral estimation parameters is best fit for this purpose. Obtaining reliable, consistent and low uncertainty spectral estimates of electromagnetic emissions measured in time-domain needs appropriate configuration and tuning of the signal processing algorithms. This paper investigates the error in the calculated spectrum for various reference signals: multitone, chirp pulses and rectangular pulses. The analysis is carried out for each CISPR band from A to D, that is, between 9 kHz and 1 GHz. After $489.6\times 10^{3}$ iterations, distributed in 1700 different digital implementations of the CISPR 16-1-1 measuring receiver, the simulations outcomes point to certain sets of parameters that showed satisfactory performance overall, being the Nutall, Kaiser, and Parzen windows with more than 75% of overlapping and using interpolation factor higher than 5, generally suitable. Calibration results are used to experimentally verify that a valid set of parameters is adequate to fulfil CISPR 16-1-1 requirements.

Electromagnetic interference has the potential to affect the functionality and performance of radio communication links. This work investigates the impact electromagnetic disturbances have on such wireless links, taking quadrature phase-shift keying (QPSK) as a representative example. The evaluation of the effects of interference on a QPSK radio link becomes relevant as it is used by the IEEE 802.11b protocol. Through simulations, we study a QPSK link subjected to narrowband and broadband disturbances. The bit error rate (BER) and the error vector magnitude (EVM) are our quality assessment metrics for evaluating the system. Two specific scenarios are analyzed: continuous wave and chirp interferences as in-band and out-band conditions. The results indicate that the applied electromagnetic interference can degrade the signal quality, resulting in high BER. Furthermore, it is observed that chirp interference largely affects the radio links more than continuous wave disturbances. The aforementioned findings support and reinforce the applicability of the analysis methodology in real-life scenarios like those characterizing healthcare settings.

Electromagnetic compatibility (EMC) is crucial when designing and operating wireless power transfer (WPT) systems for charging Electric Vehicles (EVs). WPT technology allows the transmission of electrical energy from a power source to a device without requiring physical contact. However, it can generate electromagnetic interference (EMI) that could disturb nearby electronic devices or harm people nearby. Shielding techniques are commonly employed to mitigate EMI in WPT systems. However, implementing effective shielding techniques can be complex, involving trade-offs between effectiveness, cost, and shielding weight. In this article, different types of existing shielding techniques for wireless charging systems of EVs are compared. The main concepts regarding the functioning of electromagnetic shields and the theory of the functioning of WPT systems have been also briefly introduced.

The objective of this study is to assess the impact of low-frequency electromagnetic fields (LF EMFs) generated by power infrastructure on the nearby environment. Measurements of electric (E) and magnetic (H) field intensities were conducted around high-voltage power lines, transformer stations and facilities related to them. Numerical simulations were also performed to model the distribution of the field values around real buildings in close proximity to power delivery systems. Given the ongoing scientific debate regarding the effects of EMFs on living organisms, the current analysis was based on the existing standards—particularly ICNIRP 2010 guidelines, which set the maximum allowable E and magnetic induction (B) values at 5 kV/m and 200 μT, respectively. Stricter national regulations were also examined, such as Poland’s 1 kV/m E limit in residential areas and Belgium’s 10 μT limit for B. The results showed that while most cases complied with ICNIRP 2010 standards, certain stricter local regulations were exceeded. Specifically, 9 of 14 cases exceeded Poland’s E limits, and 8 failed to meet Belgium’s B requirements. Only in one place—a warehouse near 110 kV power lines (in a critical case)—the ICNIRP limit B was exceeded. These findings underscore the variability in regulatory standards and highlight the need for localized assessments of EMF exposure.

Copyright of Elektronik Industrie is the property of Hüthig GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Electrical cables, often referred to as 'blood vessels' and 'nerves' of the industry, play a vital role in the connection of electrical devices. However, traditional cables that lack distributed filtering functions are usually the primary coupling path for electromagnetic compatibility (EMC) problems. An innovative design for a filtering cable, which incorporates insulated electrical wires coated with a specific defected conductor layer (DCL), enables it to achieve distributed filtering advantages along its axis. Microwave network analysis is employed to build the two-port network model of filtering cable, which efficiently analyzes the cascading characteristics of periodic or aperiodic filtering cables. To validate, the flexible printed circuit board (FPCB) with sawtooth dumbbell-shaped DCL and mounted by capacitors is wrapped around the stripped section of the coaxial cable to manufacture a multi-stopband filtering cable. Simulated and measured results demonstrate that the proposed filtering cable can be effectively suppressed in the stopband, which can be adjusted by changing the values of capacitors. [ABSTRACT FROM AUTHOR]

Instead of using expensive highly performing conventional pyramidal absorbers, in some cases, the use of absorbers based on very cheap eco‐friendly materials is an attractive alternative. The authors introduce a novel technique to improve the absorption bandwidth of these intrinsically low‐quality absorbers by adding a Salisbury screen at the base of the pyramidal absorber, which adds two extra design parameters. The first is the resistive sheet surface impedance, and the second is the resonance frequency of the Salisbury screen. By tuning these two parameters, better impedance matching can be obtained. This is verified with the help of a transmission line model, full‐wave simulations, and measurements. The method is applied to two different lower‐quality absorbers found in the literature. In the first absorber, the operating bandwidth is increased at the lower frequency side by 40%, and in the second one, this is about 90%. Finally, a prototype of an eco‐friendly combined absorber is designed and fabricated. The measurement validates the expected behaviour. [ABSTRACT FROM AUTHOR]

In this article, In3+ and Sc3+ ions dual-substituted NiCo nanospinel ferrites (ScIn →CoNi Fe 2 O 4 NSFs) have been synthesized through citrate-gel auto combustion method to investigate the effect of In3+ and Sc3+ ions on magnetic, and microwave characteristics. The following techniques TEM, SEM, EDX, and XRD were applied to characterize surface morphology, chemical composition, phase identification, and crystallinity of products, respectively. The XRD verified a phase formation of spinel structure with a minor amount of Sc 2 O 3 was observed for products having x ≥ 0.04. The average crystal size (D XRD) of the products was estimated within the 33–68 nm range using the Scherrer equation. SEM and HR-TEM analyses exhibited accumulating sphere-shaped particles. By fitting the room-temperature spectra obtained from Mössbauer spectroscopy (Moss), Hyperfine interactions were determined. The cation distribution shows that there is a migration of In3+ ions in the lattice in an A→B direction with increasing concentrations while the B site is preferred by the larger Sc+3. M−H plots for 300 and 10 K illustrated all products carried out with a ferrimagnetic character. An enhancement in saturation magnetization (M s) was remarked with Sc–In doping ratio up to 0.04 and thereafter a drop as the Sc–In concentration increased. The tendency in M s values might be described by correlating it to the cation distribution amongst O h and T d (octahedral and tetrahedral, respectively) sublattices. Temperature-dependent magnetization measurements were also investigated, which further confirmed the maintenance of the ferrimagnetic character throughout the temperature range 10–300 K. The peculiarities of the microwave properties have been analyzed by the measured S-parameters in the range of 6–18 GHz. It was assumed that the energy losses due to reflection are a combination of electrical and magnetic losses due to polarization processes and magnetization reversal processes in the region of inter-resonant processes. The average value of the reflection coefficient is −14.48 ... −14.24 dB. A significant attenuation of the reflected wave energy opens up broad prospects for practical applications as coatings for providing electromagnetic compatibility. [ABSTRACT FROM AUTHOR]

Frequency‐selective surfaces (FSS) with flexible treatment can be employed in various applications. This paper develops a mechanically constructed flexible double‐layer adjustable FSS based on a 3D cross‐shaped kirigami structure design. Through mechanical stretching, the kirigami structure partly adhered to the ecoflex substrate enables this FSS to modulate the resonant frequencies of two filter bands synchronously. Meanwhile, the structural deformation triggered by mechanical stretching may function as a switch to adjust the filter band with a higher resonant frequency. According to the results of EM experiments and simulations, in the absence of stretching, the undeformed FSS with a double‐layer structure has two filter bands. Compared to the undeformed configuration, the stretching induces structural deformation, which results in apparent resonant frequency shifts of both the two filter bands and the contraction of the filter band with higher resonant frequency. A buckling model that has been theoretically, cumulatively, and experimentally proven is utilized to investigate the structural deformation of this FSS caused by stretching. It is convenient to switch flexible double‐layer adjustable FSS' deformation by mechanical method. This flexible double‐layer adjustable FSS offers a new design strategy for the application of FSS, paving the route for new developments in electromagnetic compatibility. [ABSTRACT FROM AUTHOR]

The problems of electromagnetic compatibility associated with the presence of sinusoidal voltage distortions in a public network when connecting induction heating systems are considered. One of the sources of voltage harmonic emissions is the designed high-frequency induction installation for heating a graphite cylinder based on a VGT 8-50/10 power supply. The problems of low-frequency conducted interference created during the operation of the induction installation for heating the graphite cylinder at high frequencies are considered. Results of experimental studies of the sinusoidal distortion of the voltage curve in the supply network are presented. Measurements are made of the voltage total harmonic distortion factor and the nth harmonic component factor. The voltage and current curves at the input of the VGT-series power supply with a frequency of 10 kHz are obtained when connecting it to an inductor with a power of 12 and 20 kW. Voltage harmonics are measured and compared with the maximum standard parameters. The harmonic numbers at which the permissible voltage values are exceeded are recorded. [ABSTRACT FROM AUTHOR]

Recently, a safety concern of human exposure of electromagnetic field (EMF) for occupants of electric vehicles is increasing. The spatial resolution of the magnetic field sensor required for the validation was determined to be 5 mm based on the simulation. The repeatability of the small magnetic field sensor was verified using a system for generating AC magnetic field standards developed in National Institute of Advanced Industrial Science and Technology (AIST). A simulation model of a real component (battery) installed in a vehicle was improved based on measurements, and it was shown that the magnetic field level could be simulated within 3 dB. [ABSTRACT FROM AUTHOR]

A prototype of a printed circuit board (PCB) with radio frequency electromagnetic compatibility specifications is designed using the top-down methodology for the two-layer Internet of Things with free open-source hardware and software, using the following techniques: requirements, analysis, modular design, schematics, manufacturing and functional testing. The study of the influence of the design parameters is carried out applying the standards of the Printed Circuit Institute and the characteristics of the technological production process for a free multiplatform for wireless networks. Finally, functional tests of the universal asynchronous transmit and receive (UART) communication with the microcontroller, the radio modules, the general-purpose input and output pins, and the over-the-air (OTA) configuration are performed to program the board wirelessly, without the need of a universal serial bus (USB) interface. [ABSTRACT FROM AUTHOR]

In the era of the fifth generation (5G) and the Internet of Things (IoT), electromagnetic interference (EMI) poses a significant challenge. The rapid growth of wireless communication applications leads to increased electromagnetic (EM) pollution, which can have adverse health effects. To address this issue, electromagnetic absorbers (EMAs) play a critical role in eliminating EMI and reducing EM pollution between electronic devices. The focus is now on developing diverse microwave absorbing materials (MAMs) with different structures to cover a wide range of frequencies while remaining cost‐effective and effective at high angles of incidence radiation. This article comprehensively reviews EMAs, highlighting their design parameters and importance in achieving high‐efficiency absorption. The review covers absorber theory, structure, materials for various frequency ranges, and the mechanisms responsible for dissipating electromagnetic waves (EMWs). Analytical and numerical methods for modeling and analyzing EMAs are discussed, along with performance indicators and testing methods. The role of absorbers in different applications is explored, and emerging research directions for enhancing microwave absorbers are also highlighted. [ABSTRACT FROM AUTHOR]

The trend towards electrification in mobility has led to the increased use of silicon carbide (SiC) semiconductors. These semiconductors are more efficient but also present challenges related to electromagnetic interference (EMI) due to their higher voltage derivatives. This paper introduces a new high-frequency impedance model for electrical machines. The proposed model distinguishes itself from existing approaches by being entirely derived from Finite Element Method (FEM) simulations, which include capacitances in the magnetic simulation. This approach achieves a balance between computational efficiency and high accuracy across the entire frequency spectrum, ranging from 100 Hz to 50 MHz. The model provides valuable insights during the design phase and was rigorously validated using data from 28 samples of an industrial machine. [ABSTRACT FROM AUTHOR]

The study explores the detection of a harmful, wide-band interference signal, whose origin is a traditional desk LED (light-emitting diode) lamp. The interference signal was noticed on the sensitive solar spectrometer observing system, which was operating at a frequency range between 100 and 300 MHz. The interference signal was so strong and wide-band that it destroyed totally the solar observations. The study introduces two practical EMI (Electromagnetic Interference) reducing methods: ferrite cores and shielding (shielding effectiveness, S.E.). Their theoretical background is presented, and, in addition, these methods are tested in practice. The measurements and tests showed that even simple ferrite core was a very effective method to reduce interference effects. It is important that a suitable setup will be found: a single ferrite core cannot solve a whole problem. This interference problem is very demonstrative and it can be used in educational purposes at an undergraduate level at Metropolia University of Applied Sciences, Finland. This study reveals the fact that standard lamps, which are on the market, do not necessarily follow good EMC (Electromagnetic Compatibility) practices. [ABSTRACT FROM AUTHOR]

The information technology and communication (IT&C) market consists of computing and telecommunication technology systems, which also include a variety of audio devices. Preserving the confidentiality of transmitted information through these devices stands as a critical concern across various domains and businesses. Notably, spurious electromagnetic emanations emitted by audio devices can be captured and processed, potentially leading to eavesdropping incidents. The evaluation of electronic devices for potential security vulnerabilities often involves employing Transient Electromagnetic Pulse Emanation Standard (TEMPEST) technology. This paper introduces a novel approach to TEMPEST testing specifically tailored for audio devices. The outcomes of the proposed approach offer valuable insights into TEMPEST equipment testing, aiming to mitigate the potential risks posed by threats exploitable by eavesdroppers in everyday scenarios. The present work delves into the examination of two ubiquitous global electronic devices: a notebook and a pair of in-ear headphones. The symmetrical framework of this study arises from the intrinsic similarity that, despite belonging to distinct categories, both devices possess the capability to emit electromagnetic emissions that contain compromised audio signals. This assertion is substantiated by the measurement results presented herein. The proposed methodology involves the analysis of the audio amplitude modulation (AM) demodulated signal in the frequency domain. This innovative approach not only mitigates operator fatigue but also significantly reduces the testing time required for these devices and instrument running hours and leads to the development of new applications. [ABSTRACT FROM AUTHOR]

Summary: Bipolar junction transistors (BJTs) are widely used in various electronic systems, and the establishment of the electromagnetic compatibility (EMC) model for BJTs is crucial for EMC analysis of these systems, such as high‐frequency circuits. In this paper, a BJT EMC model that satisfies both functionality and EMC analysis requirements was established based on physical characteristic measurement. First, comprehensive and systematic methods for measurement and extracting SPICE parameters based on physical BJTs are presented, including a proposed curve‐fitting calculation method for extracting barrier capacitance parameters. Second, an analysis of the impact of major BJT electrical characteristics parameters was conducted, leading to the identification of important model parameters affecting BJT functionality and EMC. Finally, the primary BJT model was optimized using the simplex method, and a method for EMC analysis and verification of the BJT model was presented. The experimental and simulation results are in good agreement, and the established model meets the accuracy requirements for both EMC and functionality. Therefore, the proposed method is feasible and suitable for the EMC modeling of BJTs. [ABSTRACT FROM AUTHOR]

Summary: In order to ensure that the electromagnetic compatibility and mutual interference of multiple radar network systems meet the requirements, a 55‐W gallium nitride (GaN) high harmonics suppression (HSs) high power amplifier (HPA) microwave monolithic integrated circuit (MMIC) with an operating frequency of 5.1–6.3 GHz is designed for radar network system. An HSs method using self‐resonant capacitor integrated in the output matching network of HPA is proposed to improve the HSs characteristics. The measured results show that under the condition of 100‐μs pulse width and 10% duty cycle, the HSs are greater than 48 dBc while the output power is greater than 55 W, the power gain is 21 dB, and the power additional efficiency (PAE) is 54%, which is suitable for use in radar network system. The size of the HPA is 3.55 × 4.05 mm2. [ABSTRACT FROM AUTHOR]

Measurement of magnetic fields near the railway tracks is crucial to ensure compatibility with the operation of axle counters. According to EN 50592 standard, the magnetic field is detected with a passive magnetic coil and an oscilloscope. From previous studies, in general, there has been no in-depth analysis of how the choice of coil winding parameters could affect the coil output voltage, which then affect the measurement sensitivity, in particular the coil design based on the standard and it is applicability for electromagnetic interference (EMI) evaluation of axle counters. Therefore, this paper will explore the design of a passive magnetic coil to obtain the optimum coil output voltage within the frequency range. Simulations showed that for 10-100 kHz and 100 kHz-1.3 MHz range, the optimum number of turns happened at 60-100 and 15-60 turns, respectively. Based on that, two example coils had been built. Simulations and measurements of their frequency response were in good agreement, with a deviation less than 1.0 dB. [ABSTRACT FROM AUTHOR]

The development of new advanced functionalities, miniaturization, and the aim of obtaining optimized performance in electronic devices significantly impacts their electromagnetic compatibility (EMC). As electronic components become more densely packed on a printed circuit board (PCB), unintended coupling between components can cause electromagnetic interference (EMI). These requirements result in design restrictions that make using a board level shield (BLS) essential in reducing intra-system EMI in PCB designs. This contribution focuses on studying and characterizing a BLS solution based on combining a noise suppression sheet (NSS) with an aluminum layer to reduce intra-system EMI coupling. This hybrid solution has the advantage of providing a shielding option that does not require any electronic redesign. It does not need a footprint or a ground connection as it can be affixed over the EMI source. The solution is expected to provide higher attenuation levels than using only an NSS by combining the absorbing properties of the magnetic material and the loss mechanism of the metal. In order to verify the effectiveness of the hybrid BLS proposed solution, the magnetic near-field emissions of an EMI source are analyzed in this study. The experimental measurements and simulated results demonstrate a significant increase (51.6 dB at 1 GHz) in the shielding effectiveness (SE) provided by the proposed solution compared to a conventional NSS. [ABSTRACT FROM AUTHOR]