Impact Of Electromagnetic Interference Research Articles

Reflection on methodology of the correlation between electromagnetic interference and safety in high-speed railways

PurposeIn the continuous development of high-speed railways, ensuring the safety of the operation control system is crucial. Electromagnetic interference (EMI) faults in signaling equipment may cause transportation interruptions, delays and even threaten the safety of train operations. Exploring the impact of disturbances on signaling equipment and establishing evaluation methods for the correlation between EMI and safety is urgently needed.Design/methodology/approachThis paper elaborates on the necessity and significance of studying the impact of EMI as an unavoidable and widespread risk factor in the external environment of high-speed railway operations and continuous development. The current status of research methods and achievements from the perspectives of standard systems, reliability analysis and safety assessment are examined layer by layer. Additionally, it provides prospects for innovative ideas for exploring the quantitative correlation between EMI and signaling safety.FindingsDespite certain innovative achievements in both domestic and international standard systems and related research for ensuring and evaluating railway signaling safety, there’s a lack of quantitative and strategic research on the degradation of safety performance in signaling equipment due to EMI. A quantitative correlation between EMI and safety has yet to be established. On this basis, this paper proposes considerations for research methods pertaining to the correlation between EMI and safety.Originality/valueThis paper overviews a series of methods and outcomes derived from domestic and international studies regarding railway signaling safety, encompassing standard systems, reliability analysis and safety assessment. Recognizing the necessity for quantitatively describing and predicting the impact of EMI on high-speed railway signaling safety, an innovative approach using risk assessment techniques as a bridge to establish the correlation between EMI and signaling safety is proposed.

Electromagnetic Interference With the Mobile Communication Devices in Unmanned Aerial Vehicles and Its Countermeasures

Electromagnetic Interference With the Mobile Communication Devices in Unmanned Aerial Vehicles and Its Countermeasures

Analysis of Electromagnetic Interference Effect on Semiconductor Scanning Electron Microscope Image Distortion

Most electronic devices are susceptible to electromagnetic interference (EMI); thus, it is necessary to recognize and identify the cause and effect of EMI as it can corrupt electronic signals and degrade equipment performance. Particularly, in semiconductor manufacturing, the equipment used for image capturing is subject to various noises induced by EMI, causing the image analysis to be unreliable during the image recognition and digitization process. Thus, in this research, we aim to detect and quantify the influence of EMI on semiconductor SEM (scanning electron microscope) images. For this, we apply several useful denoising and edge detection techniques to find a clearer distorted shape from EMI-generated images and then compute five shape-related measures to evaluate the distortion. From a comprehensive experimental analysis and statistical tests, it is found that the medians of all the extracted shape-related measures of high-EMI SEM images are higher than those of both medium- and weak-EMI SEM images, and also all the p-values of the statistical tests are close to 0, and thus we can conclude that all the measures are good quantification metrics for assessing the impact of EMI on semiconductor SEM images.

Recent Advances in Electromagnetic Interference Suppression

With the increasing popularity and complexity of electronic equipment, the problem of electromagnetic interference (EMI) has become increasingly prominent. Such interference can seriously affect the performance, reliability, and service life of the device and, in severe cases, may cause system failure or communication interruption. Existing EMI suppression techniques are widely used to address this issue, and this paper provides a comprehensive overview. Firstly, it introduces the impact and harm of EMI on us and then presents two forms of EMI, namely conducted EMI and radiated EMI, better to understand the sources and characteristics of these disturbances. Three different EMI filters, the advantages of soft switching compared to hard switching, the working principle of random modulation, and emerging trends in electromagnetic shielding are then analyzed and discussed. Finally, we comprehensively summarize the advantages and disadvantages of the above four methods and point out the possible limitations of each technique in practical applications. We also propose potential future research directions, which will help to overcome the shortcomings of existing technologies and promote the development of the field of EMI suppression.

Co-cured GNP films with liquid thermoplastic/glass fiber composites for superior EMI shielding and impact properties for space applications

In this study, we explored the potential of manufacturing high concentration Graphene Nano-Platelet (GNP) films using liquid thermoplastic Elium® resin. A novel approach was adopted to co-cure manufactured GNP films with glass fiber reinforced Elium® composites to achieve superior electromagnetic interference (EMI) shielding and impact properties. The flexible GNP films were prepared using different concentrations (2 and 5 wt%) of GNPs mixed within the Elium® resin. The glass fiber/Elium® composites were prepared by infusing the liquid thermoplastic resin and simultaneously co-curing the manufactured GNP films on a heated resin infusion tool surface. The GNP films were placed at different locations within the composite i.e., as an outer layer for EMI shielding and within the laminate for impact performance. After resin infusion, the impact test specimens were hot pressed above the glass transition temperature of the Elium® resin for better dispersion of GNPs within the composite. The manufactured composites exhibited excellent EMI shielding effectiveness of more than 32 dB and impact energy absorption, strength, and stiffness increase in the order of 105 %, 48 %, and 45 % respectively, when compared with pristine Glass Fiber Reinforced Polymer Composites (GFRPCs). The results reveal the remarkable potential of the proposed manufacturing technique to achieve superior and tailorable EMI shielding and impact performance of GFRPCs without issues of agglomeration of GNP particles at high concentrations for different space-related applications.

Simulation Research on the Effect of Ultra-wideband Pulses with a Global Positioning System Antenna

With the development of drone technology, drones are gradually being applied in various industries. But with the increasingly complex electromagnetic environment, the impact of electromagnetic interference on drones is also gradually increasing. The GPS is one of the important components of unmanned aerial vehicles. This paper establishes a 1.58 GHz frequency band circularly polarized microstrip patch antenna model. It uses this model to simulate the coupling effect of UWB pulses on the front door of the GPS. UWB pulses with different polarization directions and incidence angles were selected for coupling simulation research. The results indicate that the coupling effect is closely related to the polarization direction and incident direction angle of the pulse, and the coupling signal spectra under different conditions are obtained. This result guides subsequent experiments on the coupling effect of UWB pulses on unmanned aerial vehicles and research on the coupling mechanism.

The Impact of Electromagnetic Interference from Charging All-electric Vehicles on Implantable Cardioverter-defibrillator Performance.

Electric vehicles (EVs) are growing in popularity and in general use. The effect of electromagnetic interference (EMI) caused by supercharging all-electric vehicles on implantable cardioverter-defibrillator (ICD) function has not been studied. The objective of this study was to determine the extent of the effect of EMI from charging Tesla all-electric vehicles (Tesla, Inc., Austin, TX, USA) on cardiac implantable electronic device function. A proof-of-concept study was performed to explore the potential effect of EMI from Tesla vehicles while charging the battery using a 220-V wall charger and a 480-V Supercharger. Tesla Model S and Model X vehicles were used for this study. We enrolled 34 patients with stable ICD function for the initial phase using the standard wall charger, followed by an additional 35 patients for the second phase using the Supercharger. Tracings were obtained at nominal and highest sensitivity settings while patients sat in the driver's seat, passenger seat, back seats, and facing the charging port. In each position, the device and the patient were monitored in real time by a certified technician for any inappropriate sensing and/or delivery of therapies. A medical magnet was also available on site. Emergency medical services and physician supervision were available at all times, and patients were contacted the following day to ensure their well-being. No device interactions were identified at both the nominal and highest sensitivity settings of each ICD during exposure to vehicle charging using a Tesla 220-V wall charger and a 480-V Supercharger at any of the five positions in and around each vehicle. Interaction was defined as oversensing, undersensing, mode switch, or upper rate tracking behavior. There was also no damage to any ICD, and no inappropriate shocks were administered to any patient. In conclusion, transvenous ICD function is not interrupted by EMI transmitted while charging Tesla vehicles using either the 220-V wall charger or the 480-V Supercharger.

Innovative measurement and noise reduction of voltage coupling in shielded cables for enhanced signal integrity

The reliable transmission of electrical signals through shielded cables in the presence of electromagnetic interference (EMI) remains a critical challenge for signal integrity. This paper presents a novel and comprehensive approach for measuring and reducing voltage coupling in shielded cables connected to a shielded room from a waveguide. Additionally, we introduce an innovative active EMI filter to effectively mitigate common-mode (CM) and differential-mode (DM) noises, thereby enhancing the overall signal quality. To address the issue of voltage coupling, an open circuit method with a transmission line is considered for the measurement of output voltage at the end of the shielded cable. In order to assess the impact of EMI on transmitted signals, we utilize a state-of-the-art noise separator that enables precise differentiation and characterization of CM and DM noise components. This analysis provides valuable insights into the overall noise profile, guiding the subsequent steps toward noise reduction. An active EMI filter was designed to effectively attenuate the unwanted noise. The filter intelligently targets and mitigates both CM and DM noises, resulting in improved signal integrity. The experimental setup encompasses a shielded room, shielded cables, a waveguide, and the equipment. The obtained output voltage from the shielded cable is 495 V. It is given as an input to the equipment (Cuk converter). The noises are generated when the input voltage is given; the noises are separated by using a noise separator. CM noise obtained at the output of an active noise separator is 118.8 dBµV. DM noise obtained at the output of a differential mode noise separator is 115.8 dBµV. With the active EMI filter, we achieve remarkable reductions in CM and DM noise levels. After adding a filter to the circuit, the noises are reduced below the limit line according to the International Special Committee on Radio Interference standard; the CM noise is 44.8 dBµV and the DM noise is 47.8 dBµV.

Two-Timescale Design for Reconfigurable Intelligent Surface-Aided Massive MIMO Systems With Imperfect CSI

This paper investigates the two-timescale transmission scheme for reconfigurable intelligent surface (RIS)-aided massive multiple-input multiple-output (MIMO) systems, where the beamforming at the base station (BS) is adapted to the rapidly-changing instantaneous channel state information (CSI), while the nearly-passive beamforming at the RIS is adapted to the slowly-changing statistical CSI. Specifically, we first consider a system model with spatially independent Rician fading channels, which leads to tractable expressions and offers analytical insights on the power scaling laws and on the impact of various system parameters. Then, we analyze a more general system model with spatially correlated Rician fading channels and consider the impact of electromagnetic interference (EMI) caused by any uncontrollable sources present in the considered environment. For both case studies, we apply the linear minimum mean square error (LMMSE) estimator to estimate the aggregated channel from the users to the BS, utilize the low-complexity maximal ratio combining (MRC) detector, and derive a closed-form expression for a lower bound of the achievable rate. Besides, an accelerated gradient ascent-based algorithm is proposed for solving the minimum user rate maximization problem. Numerical results show that, in the considered setup, the spatially independent model without EMI is sufficiently accurate when the inter-distance of the RIS elements is sufficiently large and the EMI is mild. In the presence of spatial correlation, we show that an RIS can better tailor the wireless environment. Furthermore, it is shown that deploying an RIS in a massive MIMO network brings significant gains when the RIS is deployed close to the cell-edge users. On the other hand, the gains obtained by the users distributed over a large area are shown to be modest.

First demonstration of a fiber optic bolometer on a tokamak plasma (invited).

A fiber optic bolometer (FOB) was demonstrated observing a fusion plasma for the first time at the DIII-D tokamak. A FOB uses a fiber optics-based interferometric technique that is designed to have a high sensitivity to temperature changes [75 mK/(W/m2) responsivity in high vacuum with 0.38 mK noise level] with a negligible susceptibility to electromagnetic interference (EMI) that can be problematic for resistive bolometers in a tokamak environment. A single-channel test apparatus was installed on DIII-D consisting of a measurement FOB and shielded reference FOB. The single-channel FOB showed a negligible increase in the noise level during typical plasma operations (0.39 mK) compared to the benchtop results (0.38 mK), confirming an insignificant EMI impact to the FOB. Comparisons to DIII-D resistive bolometers showed good agreement with the single-channel FOB, indicating that the FOB is comparable to a resistive bolometer when the impulse calibration is applied. The noise-equivalent power density of the calibrated FOB during a plasma operation was 0.55 W/m2 with an average sampling time of 20ms. The major potential effect of ionizing radiation on the FOB would be the radiation-induced attenuation, which can be efficiently compensated for by adjusting the probing light power.

Hardware Impaired RIS Assisted Multipair FD Communication With Spatial Correlation

We investigate a multi-pair full-duplex (FD) two-way communication system assisted by a reconfigurable intelligent surface (RIS), where each user-pair exchanges information via RIS. Unlike most existing works related to FD systems with RIS, we take into account an inevitable electromagnetic interference (EMI) and also consider a practical Rician channel between RIS and users, and spatial correlation owing to size constraint at the RIS. In addition we consider low-cost hardware at RIS and users resulting in impairments. We first derive an approximate expression for the achievable sum-rate of the system. We then optimize RIS phases to achieve the optimum sum-rate using particle swarm optimization (PSO) algorithm. We, through the simulation results, show the optimality of PSO algorithm and the impact of EMI and hardware impairments on the sum-rate.

Delay and Energy-Efficiency-Balanced Task Offloading for Electric Internet of Things

With the development of the smart grid, massive electric Internet of Things (EIoT) devices are deployed to collect data and offload them to edge servers for processing. However, the task of offloading optimization still faces several challenges, such as the differentiated quality of service (QoS) requirements, decision coupling among multiple devices, and the impact of electromagnetic interference. In this paper, a low-complexity delay and energy-efficiency-balanced task offloading algorithm based on many-to-one two-sided matching is proposed for an EIoT. The proposed algorithm shows its novelty in the dynamic tradeoff between energy efficiency and delay as well as in low-complexity and stable task offloading. Specifically, we firstly formulate the minimization problem of weighted difference between delay and energy efficiency to realize the joint optimization of differentiated QoS requirements. Then, the joint optimization problem is transformed into a many-to-one two-sided matching problem. Through continuous iteration, a stable matching between devices and servers is established to cope with decision coupling among multiple devices. Finally, the effectiveness of the proposed algorithm is validated through simulations. Compared with two advanced algorithms, the weighted difference between the energy efficiency and delay of the proposed algorithm is increased by 29.01% and 45.65% when the number of devices is 120, and is increased by 11.57% and 22.25% when the number of gateways is 16.

Three-dimensional interwell electromagnetic detection

Electromagnetic methods play an important role in the exploration and development of oil and gas resources and metal minerals. The ground electromagnetic method is largely limited by the detection depth and resolution in actual work. In order to improve the detection accuracy and working efficiency of interwell electromagnetic detection, this paper proposes a three-dimensional inter-well electromagnetic detection method. The method utilises one or more production wells in the production well pattern to construct a transmission galvanic couple source, which effectively reduces the shielding effect of the metal casing on the transmission signal in the well and improves the transmission signal power. The downhole and the ground receiving arrays were used for simultaneous observation, with high observation network density and detection accuracy. With pseudo-random multi-frequency signals as excitation, the working efficiency of the electromagnetic detection is significantly improved. The downhole receiving array makes the measuring electrode closer to the target geological body, increasing the response signal intensity of the anomalous body. Meanwhile, the impact of electromagnetic interference on the ground is effectively reduced, and the detection depth is increased. The ground receiving array is composed of multiple measurements points located on concentric circular measuring lines, which is beneficial for the identification of the azimuth and angle information of underground geological targets. A detection model for anomalous bodies with different parameters in the formation was established. Numerical results show that for anomalous bodies with different resistivities in the formation, the electric field response curves on the ground and the downhole receiving arrays are significantly different. Because the emission source is located on the symmetry axis of the model, the excited field is distributed axisymmetrically. The ground observation response can effectively identify anomalous bodies with different azimuths and electrical parameters in the formation. The downhole observation response is sensitive to the upper and lower interfaces of the abnormal body, and the depth information of the abnormal body can be accurately determined. The calculation results of the oilfield water injection dynamic monitoring model show that the electric field response curves on the ground receiving arrays of different measuring lines can effectively reflect the water injection process of the underground reservoir, including the direction of water penetration and the change in reservoir resistivity. The research results show that this method can better identify the resistivity characteristics, azimuth information, and depth information of anomalous downhole bodies, while effectively delineating the reservoir boundary and revealing reservoir changes. This provides a theoretical basis and technical ideas for the three-dimensional electromagnetic detection of complex interwell geological bodies.

Mitigation of Electro Magnetic Interference by Using C-Shaped Composite Cylindrical Device

The extremely low-frequency (ELF) and its corresponding electromagnetic field influences the yield of CMOS processes in the foundry, especially for high-end equipment such as scanning electron microscopy (SEM) systems, transmission electron microscopy (TEM) systems, focused ion beam (FIB) systems, and electron beam lithography (E-Beam) systems. There are several techniques to mitigate electromagnetic interference (EMI), among which active shielding systems and passive shielding methods are widely used. An active shielding system is used to generate an internal electromagnetic field to reduce the detected external electromagnetic field in electric coils with the help of the current. Although the active shielding system reduces the EMI impact, it induces an internal electromagnetic field that could affect the function of nearby tools and/or high-performance probes. Therefore, in this study, we have used a C-shaped cylindrical device combined with an active shielding system and passive shielding techniques to reduce EMI for online monitoring and to overcome the aforementioned issues. In this study, the active shielding system was wrapped with a permalloy composite material (i.e., a composite of nickel and iron alloy) as a tubular device. A C-shaped opening was made on the tubular structure vertically or horizontally to guide the propagation of the electromagnetic field. This C-shaped cylindrical device further reduced electromagnetic noise up to −5.06 dB and redirected the electromagnetic field toward the opening direction on the cylindrical device. The results demonstrated a practical reduction of the electromagnetic field.

Расчет фильтра радиопомех для судового электрооборудования

The impact of electromagnetic interference is one of the reasons for the violation of the quality of the ship's electrical equipment. Reduced interference is ensured by: individual and group filtering of electrical and distribution devices.

Protecting COVID-19 Vaccine Transportation and Storage from Analog Cybersecurity Threats

Protecting COVID-19 Vaccine Transportation and Storage from Analog Cybersecurity Threats

Application of High-Frequency Leakage Current Model for Characterizing Failure Modes in Digital Logic Gates

In this paper, a predictive model is developed to characterize the impact of high-frequency electromagnetic interference (EMI) on the leakage current of CMOS integrated circuits. It is shown that the frequency dependence can be easily described by a transfer function that depends only on a few dominant parasitic elements. The developed analytical model is successfully compared against measurement data from devices fabricated using 180 nm, 130 nm, and 65 nm standard CMOS processes through TSMC. Based on the predictive model, the impact of EMI on leakage current in a CMOS inverter is reduced by increasing the frequency from 10 MHz to 4 GHz.

MXene/polyurethane auxetic composite foam for electromagnetic interference shielding and impact attenuation

Lightweight electromagnetic interference (EMI) shielding and impact attenuating materials are vital to protect delicate components in portable electronics. While conductive foams are intriguing for lightweight EMI shielding, their impact attenuating properties remain unexplored. Herein, a MXene/auxetic polyurethane (MX/APU) composite foam is developed for multifunctional EMI shielding and impact attenuation. The MX/APU composite presents a superior EMI shielding effectiveness (SE) of 76.2 dB, 31.2% higher than its non-auxetic counterpart at the same density owing to the larger specific surface area arising from the auxetic structure. Given its ultralow density of 0.063 g cm−3, it yields a specific SE of 1210 dB cm3 g−1, placing it among the best candidates for lightweight applications. The negative Poisson’s ratio of MX/APU composite foam also delivers multifunctionalities of impact attenuation, reducing the peak force by 51.4% compared to a non-auxetic foam. This work provides a conceptually new approach to design lightweight multifunctional materials using auxetic structures.

A Review on Conductive Common-Mode EMI Suppression Methods in Inverter Fed Motor Drives

The impact of electromagnetic interference (EMI) is an increasingly important aspect of the performance of switching inverters. The challenges of managing EMI continue to grow with the emergence of wide bandgap (WBG) devices, the trend towards ever-greater integration and higher power rating. This paper reviews suppression methods for the conductive common-mode (CM) EMI in inverter fed motor drives. In order to span EMI suppression across the full system design process, the review considers both mitigation from the sources and suppression along the conduction paths. Furthermore, the shortcomings and merits of the reviewed publications are discussed, and their attenuation frequency range and attenuation level are compared. It is demonstrated that the CM EMI at low frequency is mainly determined by the PWM strategies and can be reduced or even theoretically eliminated through zero common-mode control. On the other hand, the CM EMI at high frequency is markedly influenced by the switching transients of the power devices. Thus, various drive circuits are reviewed which improve the switching behavior. Finally, the deployment of passive and active filters to suppress or compensate for the EMI is discussed.

Power quality assurance in the electrical network of the Syrian Arab Republic, using the active power filter

The set of characteristics that determine the power quality (PQ) can be used to describe the state and efficiency of the power supply system in terms of the influence of electromagnetic interference. The impact of electromagnetic interference on electrical equipment is manifested in the reduction of uptime, additional losses of active power, data loss, etc. The most common sources of interference in modern conditions are consumers with non-linear volt-ampere characteristics. This type of electrical receivers creates a distortion of the current and voltage waveform. In view of the widespread use of these power consumers in daily life and industry, special attention should be paid to the problems of harmonic distortion. This article presents the results of measurements and analysis of the quality of electricity, and also shows the effect of applying an active filter (AF) to ensure the quality of electricity in the distribution network (66/20 kV) of the city of Lattakia in the Syrian Arab Republic. The definition of the optimal capacitance of the AF dc link using the particle swarm method is given in order to minimize the total non- sinusoidal current and voltage in the studied electrical network.