Showing papers in "IEEE Electromagnetic Compatibility Magazine in 2013"

Book review: Design and modeling for 3D ICs and interposers

Abstract: It appears that 3D integration with through silicon vias (TSV) is finally here! I am referring to the mem-ory-on-logic and logic-on-logic applications where the improvement in performance, transistor density and form factor enables the electronics industry to continue the miniaturization of systems. Because of this, the timing of this book is about right.

Soft fault detection in cables using the cluster time-frequency domain reflectometry

Abstract: Faced with the continual increase in complexity of wiring networks, their reliability, in particular in embedded fields (such as automotive and aerospace industries) becomes a major issue In wiring diagnostics, reflectometry methods are commonly used They are quite efficient for detecting important damage (hard faults) such as short-or open-circuits These faults can have heavy material (eg: fires) and economical consequences Then detecting them before they happen would be very interesting and useful Unfortunately no current method is efficient enough for addressing soft faults This article proposes an original approach to overcome this problem: the Cluster Time-Frequency Domain Reflectometry (CTFDR) Based on the fact that a wire is most often in a bundle with several other wires, this method takes advantage of the resultant near end crosstalk signals to get more information about the state of the wires in the bundle To make the detection of incipient faults easier, a normalized time-frequency cross correlation function has also been used

Measurement and modeling of electromagnetic noise from LED light bulbs

Abstract: The characteristics of broadband noise radiated by LED light bulbs were investigated. According to the measurement results of the noise waveform in the time domain, LED noise can be categorized as intermittent type or non-intermittent type, in accordance with the operation of the switching power supply installed in the LED bulb. Intermittent-type noise is emitted by some LEDs supporting dimmer operation, and its repetitive bursts are synchronized with the AC mains frequency. For both types, the noise is a sequence of short pulses, each of which is generated at the instant that the power-supply circuit of the LED bulb is switched on or off. Hence, an "on pulse" and an "off pulse" are alternatively emitted. The interval of the pulses varies with time in general. A time-domain noise model representing the time-varying pulse interval and amplitude was developed by applying amplitude and frequency modulations to a regularly repetitive pulse train. As a statistical property of LED noise, amplitude probability distribution (APD) was also measured with various resolution bandwidths of the receiver. When the bandwidth was larger than the switching frequency of the power supply, Middleton's class-A model gave a good approximation of the APD. For narrower reception bandwidths down to 1 kHz, the noise can be regarded as Gaussian for non-intermittent type or intermittent Gaussian for intermittent type, respectively.

Practical EBG application to multilayer PCB: impact on signal integrity

Abstract: In this paper, signal transmission performance of single ended and differential striplines between two parallel GND planes with embedded electromagnetic band gap (EBG) structure for noise isolation in high speed digital printed circuit boards (PCB) are studied. The performances in terms of |S11|, |S21|, |Sdd21| and |Scc21| are considered in function of the stack up cross section and position above the EBG. Practical considerations for the layout strategies are drawn.

Conducted emissions in distribution systems (1 kHz–1 MHz)

Abstract: The problem of conducted emissions from modern power electronic converters for the frequency range 1-1000 kHz is reviewed. This frequency range is particularly relevant to the development of modern power converters and the new concepts of smart grid and micro grid. The uncertainties associated with measurement and predicting the performance of modern converters, the need for new standards, and new analysis techniques are discussed.

Selection and placement of decoupling capacitors in high speed systems

Abstract: The Power Integrity problem for high speed systems is discussed in context of selection and placement of decoupling capacitors. Power Integrity is maintained by damping the cavity mode peaks at resonant frequencies using decoupling capacitors. This article focuses on damping cavity mode effects in power delivery networks by the particle swarm optimization technique. The s-parameter data of power plane geometry and capacitors are used for the accurate analysis including bulk capacitors and VRM, for a real world problem. The optimal capacitors and their locations on the board are found using the presented methodology, which can be used for similar power delivery networks in high speed systems.

Elementary and ideal equivalent circuit model of the 1, 2/50¿8/20 ¿s combination wave generator

Abstract: The values of the parameters of the equivalent circuit model of the combination wave (surge) generator, which appears in the standard IEC 61000-4-5, are here derived so that open-circuit voltage and short-circuit current exactly meet the standard waveform requirements in terms of peak amplitude, front-time and duration. The time-domain expressions of the voltage and current waveforms are obtained in closed-form. The new verification procedure set in the draft edition 3 of the standard, that involves the use of an 18 μF capacitor, is discussed, and the aspects relevant to the design of the generator are analyzed.

Pulsed Hertzian dipole radiation and electrostatic discharge events in manufacturing

Abstract: A destructive Charged Device Model electrostatic discharge event can happen in semiconductor manufacturing and should be detectable from radiation that results from collapse of an electric dipole. The analytically describable radiation field pulse of CDM can be readily produced with a new instrument that creates dipole collapse at will. A coaxial monopole E-field antenna's transfer function gives the antenna signal in near-field, and experiments compare well with theory. A major feature of the antenna response to this field pulse is a bipolar "monocycle" pulse. A transmission linebased synthetic monocycle pulser, for characterizing antenna-driven ESD detectors, can be built and is described.

A simple approach of generating CPWM for reducing conducted emission in switched mode power supplies

Abstract: In this work, the problem of improving the performance of switched mode power supply (SMPS) by reducing the electromagnetic interference (EMI) using simplified chaotic pulse width modulation (CPWM) generation method is addressed. The key is the generation of CPWM by modulating chaotic pulse position modulation (CPPM) and PWM. The advantage of the scheme is the simplicity and the easy implementation in the feedback path of the converter without the need of any huge external chaotic generator circuit. The proposed method is found to be effective in reducing the peak EMI in SMPS. The effectiveness of the proposed method on spreading those dominating frequencies, compared to the conventional PWM scheme is evaluated by spectral analysis. Finally, levels of conductive EMI are experimentally verified to comply with the CISPR 22 regulations.

EMI suppression of UAV power in aeromagnetic survey

Abstract: Recently, unmanned aerial vehicles (UAVs) have become one of the latest application technologies in the aeromagnetic field Furthermore, high-precision aeromagnetic gradient surveys need higher precision magnetometers, and higher dynamic measurement precision of UAVs The problem of magnetic interference of UAVs must be solved to implement high-precision aeromagnetic surveys, as the switch mode power supply (SMPS) is one of the most important interference sources of UAVs Through the analysis of electromagnetic interference (EMI) sources of UAVs and the working characteristics of optical pumping magnetometers, this paper intends to design and optimize the switching power supply circuit, reduce the generation of EMI, and improve the measurement precision of optical pumping magnetometers

Choosing the appropriate Gas Discharge Tubes (GDT) for avionics lightning protection

Abstract: GDTs are a very effective component to suppress high powered pulsed transients such as lightning. When designing per the datasheet, one would expect a component to operate within the specified ratings. This is not always the case. Some GDTs typically violate the impulse spark-over voltage rating. The authors have noticed a belief in the industry that this is normal for a GDT. GDTs can be found that do perform according to their ratings. The purpose of this article is to dispel any belief by the reader that unpredictability of a GDT's impulse spark-over voltage is just "part of designing with GDTs". However, you do have to test.

Test methods for RF-based electronic safety equipment: Part 2 — Development of laboratory-based tests

Abstract: We describe the development of free-field test methods for wireless electronic safety equipment that replicate field-test conditions in a laboratory environment. The test methods can be used to verify the performance of wireless devices, such as those used by emergency responders, in the presence of known attenuation and under RF interference conditions. The test methods presented here were developed to support the National Fire Protection Association (NFPA) in the revision of NFPA 1982: Standard on Personal Alert Safety Systems (PASS), but would be applicable to other types of RF-based equipment as well. In Part 1, we illustrated methods for extracting performance metrics from a series of field tests conducted by NIST researchers. In Part 2, we replicate the key field test conditions in the laboratory and verify device performance under those conditions.

Smart grid EMC standards harmonization

Abstract: The Standards Development and Education Committee (SDECom) of the IEEE EMC Society has been promoting EMC principles and certification testing in the roll-out of the "smart grid" since the summer of 2008. Volunteers were assigned to attend the IEEE-P2030 meetings in White Plains, NY in September, 2009. The tag line for the New York presentation was: "The Smart Grid can't interoperate if it can't stay operating." At the January 2010 meetings in Santa Clara, all three Task Force committees within IEEE-P2030 agreed that they wanted little, if any, EMC content in their documents. The EMC Society volunteers were discouraged at being spurned by IEEE-P2030 for two years and it began to look like EMC would not be considered in smart grid standardization at all.

Radio frequency immunity testing of hearing aids

Abstract: For many Equipment Under Test (EUT), such as the hearing aids examined in this study, the desired RF immunity measurement result is that which would be measured in the most sensitive EUT orientation relative to an applied RF field. This is generally approximated from measurements at a number of predetermined orientations within a GTEM cell. This paper presents new 6 and 12-orientation “maximal sum” methods of small EUT immunity measurement, which may be considered extensions to present sorted three-input vector summation techniques. Experimental results for the new methods approached the established reference goal more consistently than did other approaches examined employing a comparable number of contributing measurements.

Book review [review of "Microstrip and Printed Antenna Design, 2nd Edition" (Bancroft, R.; 2009)]

Abstract: The knowledge of the basic principles of microstrip and planar antennas is an important skill for an EMC engineer. Not only because, as with all other radiating systems, they spread electromagnetic energy around that can unintentionally couple to other victim systems, but also for the more subtle reason that as the frequency involved in digital systems increases more and more, the proper planar structures of a Printed Circuit Board (PCB) layout can behave as planar antennas.

COMAR finding on radiofrequency safety and utility smart meters

Abstract: This Technical Information Statement describes Smart Meter technology as used with modern electric power metering systems and focuses on the radio frequency (RF) emissions associatedwith their operation relative to human RF exposure limits. Smart Meters typically employ lowpower (~1 W or less) transmitters that wirelessly send electric energy usage data to the utilitycompany several times per day in the form of brief, pulsed emissions in the unlicensed frequencybands of 902?928 MHz and 2.4?2.48 GHz or on other nearby frequencies. Most Smart Metersoperate as wireless mesh networks where each Smart Meter can communicate with otherneighboring meters to relay data to a data collection point in the region. This communicationprocess includes RF emissions from Smart Meters representing energy usage as well as therelaying of data from other meters and emissions associated with maintaining the meter'shierarchy within the wireless network. As a consequence, most Smart Meters emit RF pulsesthroughout the day, more at certain times and less at others. However, the duty cycle associatedwith all of these emissions is very small, typically less than 1%, and most of the time far lessthan 1%, meaning that most Smart Meters actually transmit RF fields for only a few minutes perday at most. The low peak power of Smart Meters and the very low duty cycles lead to the factthat accessible RF fields near Smart Meters are far below both U.S. and international RF safe-tylimits whether judged on the basis of instantaneous peak power densities or time-averaged exposures. This conclusion holds for Smart Meters alone or installed in large banks of meters.

Effect of ESD on complex programmable logic device and field programmable gate arrays

Abstract: Complex electronics devices are becoming more sensitive to electrostatic discharge (ESD). These components are being developed with higher density (extra memory bits per unit volume) and are becoming faster (MHz, GHz, THz, etc.). These upgrades in technology do not come without a "technological price". By enhancing the products' performance to meet the users' demands and requirements, one drawback is the reduction in the ESD sensitivity voltage levels. Indirect and direct air/contact discharge test has been conducted on the ALS-SDA-CPLD/FPGA trainer kit linked to the digital to analog converter (DAC) module. The Field Programmable Gate Arrays (FPGA) and Complex Programmable Logic Devices (CPLD) are found to be very ESD sensitive. The FPGA 3s50 IC was affected during the contact discharge to the input pin. There was damage to the bond pad as well as the metal top layer was damaged. The DAC ICs were affected during the ESD discharge " one due to direct ESD effects and the other due to indirect ESD effects. There was dielectric breakdown damage observed in the CPLD 9572 IC.

Practical papers, articles and application notes

Abstract: I would like to introduce three wonderful papers to all our readers. Q. Xu and Y. Zhao from the Nanjing University of Aeronautics and Astronautics, China; X. Shen and K. Chen from the Nanjing Rongce Testing Technology Ltd, China; and Y. Huang from the University of Liverpool, U. K., authored the first paper "Absorption Cross Section Measurement of a Vehicle in Reverberation Chamber for Quick Estimation of Field Strength". For electromagnetic immunity testing of a vehicle, a reverberation chamber (RC) loaded with the vehicle-under-test has to be calibrated so that the necessary input power to generate the required field strength can be determined. In this paper, the average absorption cross section (ACS) of a vehicle in the frequency range of 80 MHz — 24 GHz is measured so that the required electric field strength in the RC loaded with a car can be estimated before the RC is constructed. Once the typical ACS of a car is known, one only needs to measure the Q factor of an unloaded RC and the Q factor of the RC loaded with a car can be predicted. This is very useful before the RC is constructed, as once the RC is built the unloaded Q factor cannot be increased.

Technical committee 9 — Computational electromagnetics

Abstract: TC-9 is concerned with broad aspects of applied Computational Electromagnetic (CEM) techniques which can be used to model electromagnetic interaction phenomena in circuits, devices, and systems. The primary focus is the identification of the modeling methods that can be applied to interference (EMC) phenomena, their validation and delineating the practical limits of their applicability. Included are low and high frequency spectral-domain techniques and timedomain methods.

EMC requirements in European network codes

Abstract: Low frequency EMC is an essential part for the satisfactory operation of electric power systems. Many low frequency phenomena are part of the power quality context. Requirements on equipment connected to electrical networks are important to achieve electromagnetic compatibility. Such requirements on networks and connected equipment should be coordinated. An area of recent and increasing interest is conducted disturbances in the range of 2 to 150 kHz. This frequency range is used for communication for smart grid applications such as smart metering. At the same time, an increasing number of equipment being connected are emitting disturbances in this frequency range and higher. However, also slower voltage and power frequency variations are important in order to achieve electromagnetic compatibility.

Susceptibility of magnetic information storage to power frequency magnetic fields

Abstract: The potential for loss of magnetically stored information in the presence of power frequency magnetic fields is described in terms of fundamental physical mechanisms. Three important mechanisms are identified: (1) short term erasure when external fields are high enough to be a significant fraction of the demagnetizing field, (2) long term thermal degradation when external fields exceed a magnetic field associated with the acceleration of the natural thermal degradation process to an unacceptable level, and (3) concentration of magnetic flux by recording equipment, leading to erasure, augmented thermal degradation or corruption of the recording process. Quantitative expressions are developed for evaluation of the first two mechanisms in terms of fundamental magnetic properties of the recording medium, and a 3-D finite element simulation is used to quantitatively assess the third mechanism for a modern recording head. The first two mechanisms typically require field levels much larger than ordinary power frequency fields, but the third mechanism can lead to local fields large enough to bring the prior mechanisms into play. Results are put in the context of prior published standards and descriptions.

The evolution of Maxwell's equations through a brief critical examination of the history and background of the man and his times

Abstract: Maxwell's first published effort to describe electromagnetic phenomena was his paper "On Faraday's Lines of Force", published in 1855. In this first of four papers leading up to his Treatise, Maxwell opens his two-part presentation by stating in his introductory remarks that although much is known about the present state of electricity, areas still remain where knowledge is sparse and clear relationships have not been established. He goes on to say that it is necessary in any successful electrical theory to clearly show the connection between electricity at rest and current (moving) electricity, and the attractions and inductive effects of electricity in both states. Maxwell then asserts that in order to become familiar with the requirements of the science of electricity, one must become familiar with a large body of intricate mathematics, and that this in itself presents a significant hindrance to any progress. He goes on to express his desire to establish a method of investigation that would allow the grasp of a physical conception without creating a theory of the phenomena under study that relied on abstruse and purely analytical reasoning or that relied on a physical hypothesis before fully comprehending the various aspects of phenomena. Maxwell draws on his familiarity with Thomson's mathematical work to develop an analogical relationship between the flow of heat and the theory of action at a distance governed by an inverse square law.