By Topic

Electromagnetic Compatibility, IEEE Transactions on

Issue 3 • Date Aug. 1998

Filter Results

Displaying Results 1 - 17 of 17
  • Comments on "Near-zone gain of open-ended rectangular waveguides" [with reply]

    Publication Year: 1998 , Page(s): 294 - 295
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (30 KB)  

    The author comments that formulating the problem of radiation from open-ended rectangular waveguides (OEG) using an electric field integral equation (EFIE), Kawalko and Kanda (see ibid., vol.39, p.408-13, 1997) present results for the near-zone gains as a function of both the frequency and distance from the OEG aperture. These values can be considered to be exact. On the alternative methods, this paper observes that the approximate formulas need the measured values of the aperture reflection coefficient and the total radiated power. Kawalko and Kanda reply that the formula for the on-axis gain presented by Selvan (see Inst. Electron. Telecommun. Eng. J. Res., vol.43, p.61-4, 1997) certainly has an advantage over Yaghjian's formula (1984) in that it does not require knowledge of the total radiated power or the reflection coefficient at the aperture. However, this formula still does not account for all of the diffraction effects that occur at the aperture of the OEG. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Author's reply

    Publication Year: 1998 , Page(s): 295
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (12 KB)  

    First Page of the Article
    View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Analytical formulation for the shielding effectiveness of enclosures with apertures

    Publication Year: 1998 , Page(s): 240 - 248
    Cited by:  Papers (134)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (236 KB)  

    An analytical formulation has been developed for the shielding effectiveness of a rectangular enclosure with an aperture. Both the magnetic and electric shielding may be calculated as a function of frequency, enclosure dimensions, aperture dimensions and position within the enclosure. Theoretical values of shielding effectiveness are in good agreement with measurements. The theory has been extended to account for circular apertures, multiple apertures, and the effect of the enclosure contents View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Characterization of crosstalk noise in submicron CMOS integrated circuits: an experimental view

    Publication Year: 1998 , Page(s): 271 - 280
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (300 KB)  

    A way to characterize the crosstalk noise susceptibility for integrated circuits fabrication technologies is presented. A comparison between 0.7- and 0.35-μm technologies shows the increasing importance of crosstalk noise and, therefore, the need to consider this effect at the design level in submicron integrated circuits. An approach to measure the internal crosstalk generated by long metal interconnects based on using an RS latch sensor is proposed. An implementation and experimental measurements for 0.7-μm technology are reported, confirming the very high noise peak values View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • More investigations of leakage and nonleakage conductor-backed coplanar waveguide

    Publication Year: 1998 , Page(s): 257 - 261
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (208 KB)  

    Through rigorous full-wave analysis, the effective dielectric constant, normalized attenuation constant, characteristic impedance, and radiation pattern of two types of conductor-backed coplanar waveguides are obtained. The analytic results show that the leakage effect is not only controlled by the thickness and dielectric constant of the substrate but also by the slot width. The leakage power transforms to a radiation space wave and a surface wave, the transverse electric field diagrams in the substrate and the far-zone radiation pattern verify the leakage phenomenon. The first structure has the maximum radiation intensity in the endfire direction, while the second one which has more leaky waves radiates into the air, is better served as a radiating device. For both structures under the nonleakage condition, the characteristic impedance is sensitive to the change of the strip width but not the slot width. Using these properties, the nonleaky and leaky circuits can exist on the same circuit board by choosing appropriate circuit dimensions View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Propagation modeling of periodic laminated composite structures

    Publication Year: 1998 , Page(s): 218 - 224
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (296 KB)  

    A new model based on filament-current and thin-current assumptions is proposed to analyze the propagation problem associated with the lossy periodic multilayer structure of conducting fibers situated in a dielectric matrix. To discuss the combined effect of fibers and dielectric matrix, reflection and transmission matrices at the air-matrix, and grating interfaces together with suitable phase correction are incorporated in the model in which the fiber grating is regarded as a thin Floquet layer. To reduce the central processing unit (CPU) time, an extended filament-current model for the same multilayer structure is also examined. In this study, numerical results for the graphite/epoxy (G/E) fiber-reinforced planar laminated composite materials are presented and discussed. In particular, the parameters that influence their shielding and reflection characteristics are investigated in detail. The new model is useful in characterizing the G/E fiber-reinforced laminated composites even up to the frequency of 100 GHz View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Reduction of power converter EMI emission using soft-switching technique

    Publication Year: 1998 , Page(s): 282 - 287
    Cited by:  Papers (47)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (252 KB)  

    Measurements of conducted and radiated electromagnetic interference (EMI) emission from hard-switched and soft-switched buck, boost, and flyback converters of similar power ratings are presented. Results indicate that EMI emission can be substantially reduced by using a soft-switching technique in power converters. Thus, the soft-switching technique provides a practical and useful solution to reduce EMI emission from switched-mode power circuits. A comparison of EMI emission on the three classes of converters is also included. The flyback converter is found to be the least EMC friendly among the converters tested View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • S-parameter measurements yielding the characteristic matrices of multiconductor transmission lines

    Publication Year: 1998 , Page(s): 249 - 256
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (196 KB)  

    A frequency-domain method is presented, which yields accurate characteristic matrices of uniform multiconductor transmission lines (MTLs). It uses simple two-port network analyzer S-parameter measurements of a set of open-circuit and short-circuited MTL configurations. The method eliminates the need for voltage and current probes, which introduce errors. Transversely inhomogeneous MTLs can be accurately characterized in their quasi-TEM propagation regime. The influence of the skin effect on the inductance matrix is taken into account. The technique was used to determine the inductance and capacitance matrices of a low-loss three-conductor ribbon cable above a ground plane. Comparisons with numerically and analytically obtained data are given. Measurements are found to be repeatable for lines of length L<λ/4. The λ/4 requirement is not found to be a restriction in the megahertz regime and only plays a role as line-end effects become significant at gigahertz frequencies. The obtained accuracy is significantly better than previously reported results View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A rapid method for measuring the transfer impedance of connectors

    Publication Year: 1998 , Page(s): 193 - 200
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (208 KB)  

    An inexpensive, simple, and sensitive workbench setup has been developed to determine the transfer impedance Zt of shielded connectors. The injection current is measured by an inductive sensor integrated in the setup. The induced voltage is determined by a spectrum/network analyzer. The overall sensitivity is 3 μΩ or better; the frequency range is up to 1 GHz. No special calibration samples are needed. As a demonstration the Zt is measured for both a coaxial tube with a small hole in the shield which provides a mutual inductance of 0.1 pH. Improvements in the design of the shield of a telecommunication connector are presented. Results for some common connectors are given; the transfer impedances for these connectors ranges from 1 mΩ to more than 100 mΩ at 1 GHz View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Effect of logic family on radiated emissions from digital circuits

    Publication Year: 1998 , Page(s): 288 - 293
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (176 KB)  

    Radiated emissions were measured for simple digital circuits designed to operate with various logic families. Emissions in the near and far field were found to depend both on the circuit layout and the choice of logic family. However, the difference in peak emissions between any two logic families was found to be independent of the circuit layout. The greatest difference in peak emissions was between high-speed 74ACT logic and low-speed 4000 CMOS logic devices, with a mean value of approximately 20 dB. Emissions from a more complex circuit were compared with the measurements on simple loop circuits. Test circuits were used to measure the propagation delay, the rise and fall times, the maximum operating frequency and the transient switching currents between two successive logic gates for each logic family. Empirical formulas have been derived that relate relative peak emissions to these switching parameters. It is hoped that these will assist designers to assess the effect of choice of logic family on electromagnetic compatibility View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Capacitance matrix calculation of a wire conductor line: a new FEM approach

    Publication Year: 1998 , Page(s): 262 - 270
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (396 KB)  

    An original finite-element approach is presented to calculate the capacitance matrix of a uniform multiconductor wire line. The examined two-dimensional (2-D) domain is discretized by nodal-based triangular elements where the Laplace equation is solved. A new procedure is developed to take into account the presence of the wires, which are assumed to be located in the vertex nodes of the FEM mesh. Through the proposed procedure, the physical dimensions of the wire cross sections are considered modifying the terms of the local stiffness matrix in the finite elements surrounding the wires. A further modification of the local FEM matrices allows one to consider the logarithmic variation of the electrical potential around the wires. The procedure is efficient from a numerical point of view since it avoids the fine discretization of the nonconductive region surrounding the wire while achieving a good numerical accuracy. Numerical examples are given and compared with the analytical solutions for canonical configurations, including wires with a dielectric cover View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Electromagnetic chaos in mode-stirred reverberation enclosures

    Publication Year: 1998 , Page(s): 185 - 192
    Cited by:  Papers (17)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (300 KB)  

    We study a simple (ray optical, scalar) model of mode-stirred electromagnetic reverberating enclosures. Extensive numerical simulations reveal consistently that spatial-field homogenization and (wide-sense) deterministic chaos occur together, as the time-harmonic peak displacement of the mode-stirring wall becomes comparable to the electromagnetic wavelength. Reverberation properties can thus be synthetically gauged by Lyapounov exponents. Semiquantitative design optimization criteria are obtained and possible generalizations are discussed View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A comparison of the transmission through butt and overlap gaps

    Publication Year: 1998 , Page(s): 281 - 282
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (84 KB)  

    This paper compares the transmission through electrically thin butt and overlap gaps. It is shown that in the limit as the gap widths approaches zero, the transmissions are identical and the transmitted power can be minimized by choosing the gap depths as a quarter wavelength plus an integer number of half wavelengths View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Spherical near-field facility for microwave coupling assessments in the 100 MHz-6 GHz frequency range

    Publication Year: 1998 , Page(s): 225 - 234
    Cited by:  Papers (5)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (232 KB)  

    This paper describes a spherical near-field facility set up at the Centre d'Etudes de Gramat (CEG) to perform low-power microwave coupling assessments. Specifically, this facility has been designed to determine the coupling cross section of a complex object. However, it can also be used for the characterization of any radiating system in electromagnetic compatibility (EMC) or high-power microwave (HPM) environments. The near-field approach is shown to be complementary and to offer increased flexibility when compared to other more conventional measurement techniques. More particularly, the use of a probe array in the upper part of the frequency band significantly speeds up the near-field measurement process. Consequently, broadband and multiparameter acquisitions can be performed within acceptable duration. The examples given in this paper provide a broad illustration of the capabilities of near-field techniques for EMC and HPM applications View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • On the wide-band CW illumination of large-scale systems. II. The rhombic illuminator

    Publication Year: 1998 , Page(s): 201 - 208
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (164 KB)  

    The Phillips Laboratory has designed and constructed a continuous wave illuminator for studying the responses of large-scale systems subject to vertically or horizontally polarized electromagnetic stresses incident from the horizontal. The illuminator is developed by a nonuniform two-wire transmission line oriented over the system under test. When the wires are driven from a common mode voltage with respect to the ground a vertically polarized electric field is generated and when the wires are driven from equal but opposite voltages a horizontally polarized electric field is developed. The structure is called the rhombic illuminator since the wire configuration is very similar to the rhombic antenna. In order to illustrate the use of the illuminator, data are presented for the illumination field and for the response of an illuminated aircraft recorded at the Phillips Laboratory View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Shielding effect of a thick screen with corrugations

    Publication Year: 1998 , Page(s): 235 - 239
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (180 KB)  

    The shielding effectiveness of a corrugated thick screen is theoretically and experimentally investigated. This screen consists of a half-plane of finite thickness in which corrugations are etched on the smaller side. This structure provides a significant attenuation in the shadow region for both polarizations of the incident field; thus, it can be effectively used for protecting apparatuses from radiating interference as well as for decoupling nearby operating antennas. The shielding properties of the screen are described by a high-frequency formulation that involves closed-form expressions. An experimental setup at X band has been arranged to test the effectiveness of a corrugated screen; the field in the shadow region is compared with that of a screen without corrugations. The experimental results compare very well with those obtained by the high-frequency expressions View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Plane wave integral representation for fields in reverberation chambers

    Publication Year: 1998 , Page(s): 209 - 217
    Cited by:  Papers (204)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (296 KB)  

    A plane wave integral representation is presented for well-stirred fields in a reverberation chamber. The representation automatically satisfies Maxwell's equations in a source-free region and the statistical properties of the fields are introduced through the angular spectrum, which is taken to be a random variable. Starting with fairly simple and physically appropriate assumptions for the angular spectrum, a number of properties of the electric and magnetic fields and the power received by an antenna or a test object are derived. Many of these properties and test object responses are in agreement with other theories or with measured results. An important result for radiated immunity testing is that the ensemble (stirring) average of received power is equal to the average over plane wave incidence and polarization View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.

Aims & Scope

IEEE Transactions on Electromagnetic Capability publishes original and significant contributions related to all disciplines of electromagnetic compatibility (EMC) and relevant methods to predict, assess and prevent electromagnetic interference (EMI) and increase device/product immunity.

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Professor Farhad Rachidi
Swiss Federal Institute of Technology (EPFL)
EMC Laboratory
CH-1015 Lausanne
Switzerland
Phone: +41 (0) 21 693 26 20 (direct)
+41 (0) 21 693 26 61 (secretariat)
Fax: +41 (0) 21 693 46 62
Email: Farhad.Rachidi@epfl.ch
url: http://emc.epfl.ch