Showing papers on "Electromagnetic compatibility published in 1986"
DOI•
01 Apr 1986
TL;DR: The report describes the reverberation chamber theory of operation, construction, evaluation, functional operation, and use for performing immunity measurements and includes an estimate of measurement uncertainties derived empirically from test results and from comparisons with anechoic chamber measurements.
Abstract: This report presents the results of work at the National Bureau of Standards, Boulder, Colorado, to carefully evaluate, document, develop (when necessary), and describe the methodology for performing radiated susceptibility/vulnerability measurements using a reverberation chamber. The report describes the reverberation chamber theory of operation, construction, evaluation, functional operation, and use for performing immunity measurements. It includes an estimate of measurement uncertainties derived empirically from test results and from comparisons with anechoic chamber measurements. Finally, it discusses the limitations and advantages of the measurement technique to assist potential users in determining the applicability for this technique to their electromagnetic compatibility (EMC) measurement needs.
181 citations
01 Jan 1986
TL;DR: In this article, the capacitance and inductance per unit length of a transmission line determine the speed of an electrical pulse, and the characteristic impendance of the transmission line is derived.
Abstract: To describe how the capacitance and inductance per unit length of a transmission line determine the speed of an electrical pulse.
To obtain an expression for pulse speed and characteristic impendance in a transmission line.
To show that pulse speed is independent of geometry and with no dielectric or magnetic materials present is the same as the velocity of light.
To suggest how electromagnetic waves can propagate.
To mention special relativity as an alternative to magnetism.
65 citations
Patent•
11 Aug 1986
Abstract: A circuit layout operating in the current mode for an infrared room surveillance detector includes a high impedance operational amplifier connected directly to a pyroelement used as an infrared sensor. This results in a high sensitivity detector circuit with a low noise component in the detector output signal and maintaining a high impedance detector circuit. The detector circuit has a constant amplification over a relatively broad frequency range. The reaction resistor of the operational amplifier is chosen to have a high impedance, preferably in a range higher than 1011 Ohm. It is advantageous to take the reference voltage required for the evaluation of the detector output signal from the operational amplifier, so that aside from the simplified circuit layout, no further structural parts capable of increasing the interference sensitivity of the detector circuit are required. To further increase the electromagnetic compatibility, the threshold value comparator stage may also be located in the detector housing.
41 citations
01 Jul 1986
TL;DR: In this paper, the authors propose a novel approach to solve the problem of plagiarism in the field of bioinformatics, and propose a method to solve it by using data augmentation.
Abstract: 1 Chapter 1 . INTRODUCTION 1
18 citations
Book•
01 Dec 1986
13 citations
TL;DR: A general model is developed for the case of two interfering channels and it is used to analyzed the performance of a two-station packet radio network and a CSMA network with hidden terminals.
Abstract: Interference problems in radio networks are investigated. A general model is developed for the case of two interfering channels. The model is used to analyzed the performance of a two-station packet radio network and a CSMA network with hidden terminals. Performance evaluations for both slotted and unslotted systems are presented.
8 citations
TL;DR: In this paper, the authors present experimental data that show an overwhelming dependence of system electromagnetic compatibility (EMC) on system cable effects, rather than leakage through cracks, seams, and other box (LRU and WRA) openings.
Abstract: This paper presents experimental data that show an over-whelming dependence of system electromagnetic compatibility (EMC) on system cable effects, rather than leakage through cracks, seams, and other box (LRU and WRA) openings. A laboratory experiment compares cable-shield RF leakage from a pigtail-terminated cable with that of one that has been terminated peripherally. Theoretical justification for these empirical observations is presented. That a shielded conductor carrying an RF current i induces its own return current -i on the inside surface of the shield is proved. By confining this return current to the inside of the shield, external emissions are attenuated by the intrinsic shielding effectiveness (which can be quite a large number) of the shield.
8 citations
TL;DR: In this paper, the authors describe existing problems, basic causes, and approaches to their solutions, as well as some basic causes and solutions to their problems, which are discussed in detail.
Abstract: EMC (electromagnetic compatibility) is being largely ignored in the design of nuclear power instrumentation and control systems. As a result, EMI (electromagnetic interference) is causing costly startup delays and spurious reactor trips. This paper describes existing problems, basic causes, and approaches to their solutions.
7 citations
01 Sep 1986
TL;DR: In this article, the authors describe the establishment, content and experience of an undergraduate course in Electromagnetic Compatibility in the Electrical Engineering program at the University of Kentucky, and describe several innovative features designed to stimulate student interest and to enhance learning the principles.
Abstract: This paper describes the establishment, content and experience w ith an undergraduate course in Electromagnetic Compatibility in the Electrical Engineering program at the University of Kentucky. In addition to the topic organiza tion, this course contains several innovative features designed to stimulate student interest and to enhance learning the principles. Several small laboratory experiments are used throughout the course to give hands-on experience with modern test equipment and to illustrate the basic principles. Students are required to construct a simple digital device and incorporate the EMC design principles of the course in order to have it pass the FCC Class B radiated and conducted emissions tests. A key ingredient in the success of this course is the cooperation and encouragement of local industry—the Information Products Division of the International Business Machines Corporation at Lexington.
6 citations
Journal Article•
4 citations
01 Jan 1986
TL;DR: In this article, a mathematical model that allows the fundamental mechanisms of gap-type noise to be simulated is presented, which can be used to derive an expression for the demodulated power spectral density (PSD) compared with field observations.
Abstract: Electromagnetic disturbance from power lines is one of the main sources of man-made noise affecting communications in the high-frequency radio band. Most radio disturbances generated by power lines are of two types: gap-type noise caused by electric discharges across line hardware, and corona noise caused by the partial breakdown of the air due to the high electric fields around transmission-line conductors. While the physical mechanisms of these noise types have been investigated in detail, these studies have not yet been used to develop noise models for the evaluation of communication-system performance. This paper presents a mathematical model that allows the fundamental mechanisms of gap-type noise to be simulated. With this model, the effect of gap-type noise processes on various high-frequency communication systems can be determined by direct computation as well as by experimental observation. The mathematical model was used to derive an expression for the demodulated power spectral density (PSD) compared with field observations.
26 Mar 1986
TL;DR: This paper is a preliminary report of a real-time expert system which is concerned with the detection and diagnosis of electrical deviations in on-board vehicle-based electrical systems.
Abstract: This paper is a preliminary report of a real-time expert system which is concerned with the detection and diagnosis of electrical deviations in on-board vehicle-based electrical systems. The target systems are being tested at radio frequencies to evaluate their capability to be operated at designed levels of efficiency in an electromagnetic environment. The measurement of this capability is known as ElectroMagnetic Compatibility (EMC). The Intelligent Deviation Diagnosis (IDD) system consists of two basic modules the Automatic Data Acquisition Module (ADAM) and the Diagnosis System (DS). In this paper only the diagnosis system is described.© (1986) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
01 Jan 1986
TL;DR: A computer model is described to evaluate airborne radio performance in a mixed environment of friendly and hostile emitters and a new performance criterion, the communications operability volume, is introduced.
Abstract: A computer model is described to evaluate airborne radio performance in a mixed environment of friendly and hostile emitters. A new performance criterion, the communications operability volume, is introduced. This criterion permits operational, scenario-based comparisons of various radio designs over a range of interference environments. Communications operability volumes can be calculated for different waveforms, receiver antenna patterns (including adaptive arrays), and detection thresholds. An empirical propagation algorithm is used to calculate path losses and/or maximum communications range. The computer model provides several types of graphic outputs that are used to compare antijam or electromagnetic compatibility performance for different radio designs at various locations relative to the sources of interference in a scenario.
TL;DR: In this paper, the usefulness of ferrites in optimal radar absorber design may need consideration of compatibility with other materials and distributed components, as well as the compatibility of the ferrites with other components.
Abstract: The usefulness of ferrites in optimal radar absorber design may need consideration of compatibility with other materials and distributed components.
01 Sep 1986
TL;DR: Southwest Research Institute conducted a mail survey of hospitals across the United States to help identify current RFI/EMC problems, designed to qualify electrical/RFI/ EMC problems occuring with hospital equipment.
Abstract: Manufacturers of medical and ancillary hospital equipment are interested in the Radio Frequency Interference/Electromagnetic Com patibility (RFI/EMC) environment in hospitals. Southwest Research Institute (SwRI) conducted a mail survey of hospitals across the United States to help identify current RFI/EMC problems. The SwRI ques tionnaire was designed to qualify electrical/RFI/EMC problems occuring with hospital equipment. From this information, a picture of the RFI/EMC environment of a typical hospital could be drawn.
01 Feb 1986
TL;DR: This paper suggests guidelines for EMC planning of military communication systems and a methodology to be followed in the EMC design of these systems.
Abstract: Military Communication Systems are crucial for the three services both in peace time and during operations. It is essential that the Electromagnetic Compatibility (EMC) aspects of these systems are considered at every stage of their life cycle in order to ensure that they work without EMI problems in a given environment or when installed on a given platform. Sophisticated techniques like Spread Spectrum Techniques and complex modulation schemes for digital data transmission are being employed in major systems. The impact of these techniques on the EMC aspects of frequency assignment, spectrum management and spectrum pollution is required to be analyzed in detail. Achievement of Intrasystem EMC by proper EMC design of various subsystems and system integration also assumes importance. This paper deals with both Intersystem and Intrasystem EMC design and suggests guidelines for EMC planning of military communication systems and a methodology to be followed in the EMC design of these systems.
01 Jan 1986
TL;DR: In this paper, a new method for determining the radiation characteristics of leakage from electronic equipment or other unintentional radiators of interference is presented, and the theoretical background and specific measurement procedures for the method using a transverse electromagnetic cell are outlined.
Abstract: A summary of a new method for determining the radiation characteristics of leakage from electronic equipment or other unintentional radiators of interference is presented. The theoretical background and specific measurement procedures for the method using a transverse electromagnetic cell are outlined. The theory and measurements have been verified in referenced work by the results of a simulated theoretical example and an experiment using a spherical dipole radiator. Mathematical analysis of the uncertainties in the final, extracted results when the experimental data are degraded by the background noise and measurement imperfections is also available.