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This paper proposes the methods of high intensity radiated field (HIRF) testing for civil aircraft. It introduces how to eliminate the background noise and select the frequency list for HIRF testing at first. Then, the method of LLSC calibration and LLSC test is proposed along with an automatic test system of LLSC testing. After that, how to design a mode stirrer and validate the performances of it...
The optical fiber communication network is featured by strong anti-interference, good signal quality and other advantages. However, there are many equipment for the conversion of photoelectric signal is widely used in optical fiber communication network. When they are subjected to intentional electromagnetic interference radiation, it will affect their work, and even damage to the equipment, endangering...
Loop antennas are widely used in various military and civil test applications in order to measure the magnetic fields especially below 30 MHz. They are commonly calibrated as per the standards IEEE 291 and SAE-ARP 958. Although there are a good number of researches in literature about the comparisons of loop antenna calibration methods, we brought the comparison measurements one more step further...
The novel volume integral equation (VIE) method was developed for an accurate analysis of low frequency (LF) electromagnetic (EM) fields induced inside human body voxel model. To improve stability of LF solutions, we introduced two sets of unknowns: electric voluminous currents and surface charges defined on interfaces between different materials. At low frequencies, an efficient version of VIE was...
The influence of two short equivalent lines on the accuracy of the asymptotic method for electromagnetic field coupling to transmission line (TL) at high frequency is investigated. Firstly, the induced current distribution along the TL in terms of different lengths of two short lines is analyzed. It is indicated that the calculated induced current along the line by using asymptotic method is not reliable...
At mass coverage of populous urban areas by wireless communications services the microcellular structure of cellular radio networks and tendency of further reduction of its sites are occur. However, the widely used empirical radio wave propagation models (Okumura-Hata, COST231-Hata, COST231-Walfish-Ikegami, Lee, etc.), as a rule, are defined for propagation on distances between mobile and base stations...
The electrical behavior of a cavity with arbitrary shape, lossy walls and lossy filling material, which is excited by electrically small current elements, is represented by a novel broadband Foster-type circuit based on the eigenmodes of the cavity. This model is inherently stable in the time domain and allows the simulation of arbitrary nonlinear loads with a commercial circuit simulator. The convergence...
A new adaptive terahertz absorbing screen providing a reflection coefficient lower than −10 dB in the frequency range 0.6–2.2 THz and with total thickness around 70 μm is proposed. The designed Salisbury screen, backed by a perfect electric conducting plate, consists of a first graphene layer as lossy sheet and two spacers made of polyethylene terephthalate (PET), separated by a tunable graphene/SiO2...
This paper presents an accurate and efficient time-domain approach for analyzing the coupling of transient electromagnetic fields into cable systems with arbitrary linear networks at terminations. Some nonlinear elements in termination circuits are also considered. The approach is based on hybridization of three different methods. First, the discontinuous Galerkin time domain (DGTD) method is used...
Measuring the scattering parameters of electric components is normally established by using suitable high frequency galvanic contacts like those of coaxial connectors. Methods for Contactless Vector Network Analysis (CVNA) are rare but could promise advantages in many respects. In this paper, a pre-existing concept for Contactless Vector Network Analysis using a special sort of current probes as contactless...
This work demonstrates in a theoretical manner how to free certain bandwidths for low frequency communication systems, in an electromagnetically polluted environment by canceling spectral lines of a present disturbance signal. In many cases electromagnetic interference (EMI) is system-intrinsic and the designers have influence on some of its parameters. In case of a combination of switched mode power...
We present EMI simulations of a silicon carbide MOSFET traction inverter. The simulations are based on a transient circuit simulation and frequency domain simulations of different 3D geometry models. In a first step, an equivalent circuit is derived from parts of the geometry model and combined with an analytical model of the MOSFETs and an equivalent circuit model of the DC link capacitor. The results...
This paper presents a metamodel based on the sparse polynomial chaos approach, well adapted to high-dimensional uncertainty quantification problems, applied for the analysis of crosstalk in printed circuit board microstrip traces. It enables to estimate, with a low computational cost compared to Monte Carlo (MC) simulation, statistical quantities and provides a sensitivity analysis of the crosstalk...
In order to study the ability of the ferrite magnetic ring to combined protection to the high altitude electromagnetic pulse (HEMP) and lightning, this paper studies the HEMP and lightning protection of ferrite magnetic ring based on an 500 kV open-type substation by experiment of PSCAD program. The results show that the ferrite magnetic ring can suppress the magnitude of the intrude current, effectively...
The coupling devices for RF immunity testing in close proximity defined in the new basic standard IEC 61000-4-39 are TEM horn antennas. The required parameters for TEM horn antennas are investigated based on simulations and measurements. In addition the practical relevance of the test method has been investigated with respect to the field properties as well as for an example of a practical mobile...
This paper presents the main results of a thesis work dedicated to the Specific Absorption Rate (SAR) risks in High-Frequency (HF), Very High-Frequency (VHF) and Ultra High-Frequency (UHF) frequency bands. The main goal of this thesis is to enhance SAR method validation of radio military exposure near high power antennas. It will permit to reduce cost and delay of SAR validation and quantify the actual...
The purpose of this work is to establish a numerical framework capable of generating simulation data with the same statistical properties as the represented electrical reverberation chamber (ERC). While an ERC whose resonating volume is geometrically varied produces randomly distributed fields, a numerical simulation is a deterministic system. However, the statistical distributions of electrical fields...
In the first part of this paper the results of measurements on the shields of signaling cables are presented. This meant measuring the shield's inner and outer surface impedances in the function of frequency and current as well. These impedances used to define the inner screening factor, which describes the effectiveness of the screening on given frequency, or on given current. The second part of...
To examine the microwave electromagnetic field (EMF) characteristics inside carbon fiber reinforced plastic (CFRP) structures, the quality factors (Q-factors) of reverberation chambers constructed of either CFRP or aluminum are evaluated and compared. In the CFRP structure, the four sidewalls and ceiling, which are originally made of aluminum, are replaced by CFRP panels, and then the uniformity of...
Modelling of complex wave sources is an important topic in several scientific and engineering communities. In the context of electromagnetic compatibility, the complexity of field emissions from extended and broadband planar sources allows for the use of statistical methods to characterise the development of far field interferences from near field scanning at planes parallel to the source. We review...
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