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Recent all–digital spread–spectrum clock generators allow the synthesis of clock signals with a discontinuous frequency behavior. Following the electromagnetic interference (EMI) test guidelines, this paper investigates for the first time the peak-level reduction of the spectrum (modulation gain) achievable by using discontinuous frequency modulated signals in spread–spectrum clocking applications. In this paper, the spectrum of discontinuous frequency clock signals, measured by a spectrum analyzer in a peak–hold mode, is computed analytically in closed form. This expression is used to formulate the problem of finding the optimal discontinuous frequency modulated waveform as the solution of a nonlinear differential equation. A suboptimal modulation waveform, which can be computed in closed form, is also derived in this paper. To verify the effectiveness of developed approach, the spectrum of frequency-modulated clock signals with different modulation waveforms and different modulation parameters (frequency deviation, modulation frequency) has been calculated for two different spectrum analyzer resolution bandwidths (100 kHz, 1 MHz). The obtained results show that discontinuous frequency modulations can result in an improvement of 1.5–2 dB in comparison to continuous frequency clock signals. [ABSTRACT FROM PUBLISHER]

A novel method to accurately and efficiently model the interaction between radiating devices is proposed. Whereas previous work of the authors dealt with singleport devices (antennas), this paper constitutes an important extension to actual multiport devices, as such paving the way for electromagnetic interference assessment of real-life (sub)systems early in their design cycle. The method solely relies on the knowledge of the radiation patterns of the different ports of the devices, which can either be measured or simulated using a solver of choice. These patterns are then used to compute the electromagnetic interaction between the devices that may be positioned in each other's radiative near-field (Fresnel region) or far-field (Fraunhofer region). Furthermore, in the model, their relative positions and orientations can be altered at a very low computational cost. The technique is thoroughly validated and illustrated, demonstrating its appositeness to study the electromagnetic compatibility behavior of the multiport devices. [ABSTRACT FROM AUTHOR]

In the electromagnetic compatibility behavior of power electronic converters, parasitic magnetic couplings between components are one of the main causes of dysfunctions or poor filtering. These couplings may be either conducted or near-field interferences. To handle interaction problems, full knowledge of these magnetic couplings is essential. This paper is an overview of the work on near magnetic field interference undertaken in the last 15 years by the International Maxwell Laboratory. This paper details a predictive method that accurately and efficiently calculates near magnetic field coupling between two sources. The method uses near-field multipolar expansion in spherical harmonics of electromagnetic sources to determine close magnetic coupling between two sources from their equivalent models. This paper also shows how theoretical developments of large loop antennas have evolved from the van Veen antenna, a model with only two degrees of freedom, to a more complex model in terms of degrees, order, and types of harmonics. In parallel, it describes developments in the measurement method that provides input to the theoretical model. To illustrate how the research has evolved, we discuss coupling between two complex sources to assess the accuracy of this predictive method. [ABSTRACT FROM PUBLISHER]

This paper presents an algorithm for finding carriers of frequency-modulated (FM) and amplitude-modulated (AM) electromagnetic (EM) emanations from computer systems. Computer systems create EM emanations across the RF spectrum making it difficult, error-prone, and time consuming to find the relatively few emanations that expose sensitive information. One of the most common and simplest mechanisms for information leakage occurs when an amplitude or a frequency of an existing strong signal (e.g., a processor or memory clock) is amplitude or frequency modulated by a system activity. If the system activity can be linked to sensitive information, this results in information leakage. We present an algorithm for automatically finding these AM and FM signals, demonstrate the algorithm's performance on several different types of processors and systems (desktop, laptop, and smartphone), and compare the results to an exhaustive manual search. We also verify that all signals identified by the algorithm can be traced to plausible unintentional modulation mechanisms to illustrate that these signals can potentially cause information leakage. This algorithm can be an important tool for system designers to quickly identify circuits that are leaking sensitive information. [ABSTRACT FROM PUBLISHER]

This paper aims at developing a spectrum analysis approach to suppress the electromagnetic interference (EMI) and the current harmonics in an active power filter (APF) via periodic carrier frequency modulation sinusoidal pulsewidth modulation (PCFMSPWM) control signals based on double Fourier series. The APF EMI concentrated at multiples of switching frequency results from the concentrative current harmonics. A novel spectrum analysis method based on PCFM and double Fourier series is developed to reduce the APF current harmonics. In this scheme, the optimal frequency deviations and waveforms of periodic signals are selected by calculating the spectrum of PCFMSPWM control signals. As a result, the modulation signal which has the best suppression effect on the interference peak is obtained and the quantitative design of PCFM is realized. Simulations and experiments of an APF driven by standard SPWM and triangular PCFMSPWM are implemented. On the basis of the simulations and experiments, effectiveness of triangular PCFM in alleviating APF current harmonics and EMI are validated. [ABSTRACT FROM AUTHOR]

In this paper, the interference emission levels of domestic induction heating appliances, which are tested out by the triple-loop antenna proposed by Van Veen and Vergerboet, are analyzed to estimate the measured values from numerical simulations. The purpose of this study is to propose an alternative method to evaluate the emission level of consumer goods in the early stages of the development procedure, prior to perform measurement in a prototype. The constitutive parts of the system have been separately analyzed and modeled, including the equipment under test. Three different blocks have been considered: the inductor heating system, the magnetic coupling between the electromagnetic fields of the system and the output levels of sensor antennas, and, finally, the processing performed by the electromagnetic interference receiver. The description given in this paper provides interference levels at frequencies ranging from the operational switching frequency of the apparatus, typically few tens of kilohertz, to about 1 MHz. Finally, the proposed analysis is verified by comparison of the numerical estimated emission levels and test measurements. [ABSTRACT FROM AUTHOR]

In this paper, a novel compact and wideband common-mode suppression structure is proposed, which is composed of a meander line and several quarter wavelength resonators. A simple and accurate transmission line model is employed to describe the stopband behavior of the proposed structure. The resonance frequencies and harmonics of quarter wavelength resonators are employed to form stopbands of the common mode. Those stopbands together with the stopband of the meander line are connected in series, which are useful to expand the common-mode suppression bandwidth. Meanwhile, compensation strips are proposed to reduce the insertion loss of the differential mode. A reduction of 15 dB of common-mode propagation above 0.8 GHz is obtained by using the proposed hybrid structure. The measurement results of printed circuit boards, which are designed and fabricated on the simulation model, show good correlation with the simulation results. [ABSTRACT FROM AUTHOR]

Active cancellation of disturbing signals is a common method in EMC. In this paper, a specialized strategy is presented to minimize the disturbing harmonics of stationary clocked systems by injecting an appropriate harmonic cancellation signal with an adjustable signal synthesizer. The optimum cancellation signal is found via a convenient and robust adaptive approach. Each destructive harmonic is generated individually, and the cancelation signal is the superposition of a set of sinusoidal signals. As a special feature of this method, many troublesome effects, like delays or complex frequency characteristics, can be compensated easily. Several implementation variants can be derived from this general approach. Here, the variant, continuously adapted harmonics cancellation (CAHC), is considered. The system's limitations due to the ADC, the DAC, and the synchronization are described. An FPGA-implementation of CAHC is presented and applied to a dc/dc converter in an automotive component measurement setup to demonstrate the effectivity of the method. [ABSTRACT FROM AUTHOR]

Most photovoltaic (PV) systems are composed of series and parallel inverters. The electromagnetic interference (EMI) mainly comes from the off–on of inverter switches with pulsewidth modulation (PWM). The output EMI peaks of PV systems would increase markedly due to the interference superposition effect caused by parallel inverters, whose carrier initial phases are in phase or close to each other. In this paper, an auto-screening carrier phase-shift scheme is proposed to weaken the superposition effect of EMI peaks and to get the result of reverse offset at its best. In a PV system, through voltage detections and spectrum estimations of each inverter with a series of phase-shift carriers, a best carrier phase of each inverter is obtained automatically to minimize EMI peaks of the PV system. In order to avoid the conflict that the screening processes of two or more inverters are underway at the same time, a specific frequency signal is output temporarily as an occupancy mark in one of the inverters. The feasibility and effectiveness of the proposed scheme are verified by experimental results in a PV system composed of four parallel single-phase inverters. [ABSTRACT FROM AUTHOR]

In this paper a new procedure is presented for predicting the effect of electromagnetic interference (EMI) on the dc shift, harmonic, and intermodulation performance of an NMOSFET current mirror with a capacitor connected between the mirror node and the ground. Closed-form approximate expressions are obtained for the dc and the amplitudes of the fundamental, second- and third-harmonic, and second- and third-order intermodulation output current components resulting from exciting the mirror by a dc biasing current plus a superimposed multisinusoidal EMI. Simulation results are included. [ABSTRACT FROM PUBLISHER]

In this article, multilayer ceramic capacitors (MLCCs) induced acoustic noise is studied through simulation investigation of the vibration behavior of the printed circuit board (PCB). The board vibration theory is briefly summarized to understand the key parameters influencing intrinsic board vibration properties. The identified key parameters are the thickness, mass density, and Young's modulus of each board layer. To accommodate the parameter variations in real board fabrication process, a statistical simulation model for PCB vibration modal response is proposed. The simulation results have shown good correlation with the measurement. The sensitivity analysis of board vibration properties to the identified parameters of each layer has also been conducted through simulation. Based on the derived intrinsic board vibration properties, the PCB vibration behavior with capacitor as forced excitation is further analyzed through modal superposition. The simulated results also exhibit good correlation with measurement. With the proposed simulation methods, engineers can evaluate the board vibration behavior at early design stage and some design guidelines for placing MLCCs can be derived to reduce acoustic noise. [ABSTRACT FROM AUTHOR]

Although the dc/dc converter as a common power supply is compatible with the electromagnetic compatibility standard, it may still bring the peak interference generated from one nonlinear load to the other loads. In this paper, a novel filter is designed in a low-voltage buck converter to suppress some extra peak harmonics generated from a nonlinear load, i.e., a pulse width modulation switching circuit. This filter is a variable capacitance filter (VCF) whose active devices are working in the linear areas. The capacitance of the filter is controlled to vary with the change of the switching load's carrier-frequency in the scheme. The impedance of the VCF can not only be matched with the switching load, but also avoid the mismatch effect from the parameter drift caused by the aging of the components. Thus, the VCF can suppress the introductive peak harmonics from the switching load at its carrier-frequency, especially the peak harmonics in the carrier-frequency region when the carrier-frequency modulation is used as the control strategy in the switching load. The feasibility and validity of the VCF are proved by simulations and experiments in a low-voltage buck converter, in which a boost circuit is working as one of its loads. [ABSTRACT FROM AUTHOR]

This paper deals with the use of the Bayesian approach to inverse an underdetermined magnetostatic problem based on spherical harmonic expansion. Identification of the spherical harmonic coefficients is helped thanks to some a priori information. This information comes from a numerical model statistically studied to define an average-state vector and a covariance matrix. The whole approach is applied for the study of the magnetostatic field inside an electric vehicle, created by its power circuitry. It demonstrates the strength of merging a priori information and measured information in order to obtain an efficient identification of magnetic sources created by a complex set of conductors. [ABSTRACT FROM AUTHOR]

This paper addresses the simulation of the conducted electromagnetic interference produced by circuits with periodically switching elements. The proposed method allows for the computation of their steady-state responses by means of augmented linear time-invariant equivalents built from circuit inspection only, and standard tools for circuit analysis. The approach is demonstrated on a real dc–dc boost converter by comparing simulation results with real measurements. [ABSTRACT FROM AUTHOR]

In the electromagnetic compatibility (EMC) behavior of power electronic converters, magnetic parasitic couplings between components are one of the main causes of dysfunctions or bad filtering (e.g., in EMC filter). These couplings could be as conducted or near-field interferences. In order to handle interaction problems, a complete knowledge of these magnetic couplings is then necessary. Our study is focused on near magnetic field's interferences. Indeed, the characterization of electromagnetic field in power electronics is still in active research. This paper details a predictive method that calculates accurately and efficiently the near magnetic field coupling between two sources. By using the near-field multipolar expansion in spherical harmonics of electromagnetic sources, the close magnetic coupling between two sources is determined from their equivalent model. It is shown that the increase in degree up to the fourth provides a more precise representation of the elements and thus a better accuracy of the near-field coupling prediction. Also, theoretical and experimental developments will be presented. The coupling between two complex sources will be considered to validate the predictive method. [ABSTRACT FROM AUTHOR]

Electronically initiated explosives can have unintended electromagnetic emissions, which propagate through walls and unshielded containers. These emissions, if properly characterized, can be used to quickly detect explosive threats. In this paper, an analytic model is developed for the unintended emissions of clocked digital devices, such as microcontrollers, which can be used as initiators. It is demonstrated that these emissions are clock-dependent, periodic train of impulses. An autoregressive model of these clock emissions is developed, and the model is validated using measurements of an 8051 microcontroller. Existing algorithms, including pitch-estimation and the epoch-folding algorithm, are surveyed for detecting generic digital devices with unknown clock frequencies and emissions characteristics. A novel detection algorithm, which uses pitch estimation, is proposed. The model is used, in a simulated environment, to evaluate the noise performance of the proposed algorithms. Results indicate that the pitch-estimation techniques are robust against jitter and have a 4-dB sensitivity improvement over epoch-folding algorithms. [ABSTRACT FROM AUTHOR]

This paper provides a comprehensive study on and a collective prediction approach to the responses of a microstrip microwave oscillator illuminated by an external plane wave. The field-induced responses are complicated and can be divided into periodic, quasi-periodic, and chaotic regimes. These responses can be effectively simulated by a harmonic-balance simulator based on the newly proposed approach. The main effort of this approach is to incorporate the equation-based equivalent sources with an auxiliary source embedded in the circuit schematic, which is then solved by the circuit simulator. The equivalent sources stand for the plane-wave incidence while the auxiliary source is added to search for the nontrivial solutions. Also based on this approach, the stability property of the obtained solutions can be confirmed, and the predictions of the phase-noise degradation and the demarcation of the chaotic response are provided. A 2.5-GHz oscillator is created and simulated by this approach, and the measurement performed inside a standardized anechoic chamber is compared to the simulation with good agreement. Indeed, the oscillator is observed to have the periodic, quasi-periodic, and chaotic responses. In the periodic regime, the oscillation may be locked or blocked by the external incidence. In the quasi-periodic regime, the oscillation frequency shifts and the phase noise varies. In the chaotic regime, the output spectrum is continuous. [ABSTRACT FROM PUBLISHER]

This paper presents a simple and practical method to reproduce and predict the time-domain behavior of the radiated electromagnetic fields of microwave circuits. The previously developed frequency-domain model is extended toward predicting the large-band electromagnetic radiations and thereby the time-harmonic fields. Fourier-series-based method is used in order to transform the frequency-domain near-field measurement data into time domain for digital applications. A cutting-edge extraction procedure is developed so as to extract the large-band model parameters in a single step. The modeling method is validated on a high frequency transmission line and on a hybrid coupler. The modeled results are compared with time-domain simulations performed in CST Microwave Studio. [ABSTRACT FROM AUTHOR]

We introduce, for the first time, a new class of flexible bandstop frequency selective surface that provides very stable nearfield (NF) characteristics in the X-band, unlike the traditional FSSs. The structure's building block uses two layers of patches to reach the NF stability through their interaction. Periodic convoluted square loops on one side of a flexible substrate and periodic square loops on the other side are used. The created multipole resonator operates by changing the local coupling effect between the cells on the sides. It enables a localization of capacitive and inductive characteristics, which provides spatial filtering for both near- and farfield. An accurate equivalent circuit model is developed to validate the coupling effect. It is shown that four operating modes could be defined for the structure, each of which provides specific behavior. A realization for each operational mode is also provided. An X-band NF shielding of at least 30 dB at the center frequency and maximum 10-dB fractional bandwidth of 32% are obtained. The superiority of the NF shielding performance is shown through comparisons among conventional shields. Finally, the measurement results justify the reliable NF shielding performance. [ABSTRACT FROM AUTHOR]

The ability of reverberation chambers to generate high-intensity field levels from relatively low-power input signals is reexamined for the case of time-reversed signals, proving that they lead to a higher efficiency. Moreover, the strong statistical spread typical of time-harmonic excitations can be dramatically reduced, thus, improving the reliability of radiative tests, while limiting the need for a large number of independent realizations. The two excitation schemes are compared when forcing their respective input signals to display the same peak instantaneous power. Experimental results are provided, supporting the conclusions of our theoretical analysis. [ABSTRACT FROM PUBLISHER]

Common-mode (CM) noise on differential microstrip lines can be suppressed by PCB-embedded filters. These filters use resonating or broadband structures such that only the field from the CM signal couples to them. Based on a quarter-wavelength resonator, a new PCB filter is designed having an electrical size of only 0.15 λ × 0.065 λ, where λ is the effective wavelength in the CM filter. Its interdigital structure is also capable of suppressing higher order harmonics of the CM signal and can be used for USB 3.0 to mitigate electromagnetic interference. Further, a novel broadband suppression structure is described that uses magnetically lossy material to suppress the CM signal from 4.6 to 20 GHz without strongly affecting the intended differential signal. [ABSTRACT FROM AUTHOR]

With the rapid development of wireless communication, the requirements of high-integration and low-cost radio frequency (RF) front-end modules in mobile phones result in more usage of silicon-on-insulator field effect transistors (SOIFETs) for the manufacturing of RF switches. However, the nonlinear behavior of SOIFET switches in off-state always produces unwanted harmonics distortion interference when they are excited by a large signal. In this article, we simplify the well-known physics-based surface potential model to an interelectrode nonlinear capacitance (INC) model since it adequately describes the harmonic effects produced by the transistor. The INC model, referred to as the coarse model, cannot match the behavior of the real switch, since many parameters of the switch cannot be accurately determined. This article proposes a novel dynamic neuro-space mapping network model, referred to as the fine model, to optimize the INC model. The proposed model takes advantage of the high accuracy of the fine model and the fast speed of the coarse model. Ultimately, the proposed method can accurately predict the harmonics interference for SOIFET switches in the complex RF front-end environment and provides an intuitive guideline under the design stage to prevent EMI problems. [ABSTRACT FROM AUTHOR]

This article investigates the conducted-emission (CE) suppression characteristics of electromagnetic interference (EMI) filters used in power-electronic equipment by time-domain circuit simulation. An operational definition of insertion attenuation is introduced by comparing the CE in the absence and in the presence of the EMI filter. For the sake of exemplification, the analysis focuses on switched-mode dc–dc converters. It is shown that the EMI-filter attenuation behaves differently from the standard insertion loss (IL) and exhibits peculiar properties in these circuits. Namely, its response is known at discrete frequencies where the converter generates CE and may strongly depend on the harmonic index so to jump between quite different levels from a harmonic component to the next one, with a pseudoperiodic behavior, which can be related to the duty cycle. This effect is caused by circuit nonlinearity and is partially mitigated if the simulation accounts for two practically relevant aspects: random instability of the duty cycle and resolution bandwidth of the EMI receiver. The dependence of the common-mode (CM) and differential-mode attenuations on the loading conditions and duty cycle is analyzed, and it is shown that linear IL models provide reasonable predictions of CM attenuation only. Finally, experimental evidence of the unveiled phenomena is presented. [ABSTRACT FROM AUTHOR]

In this article, time diversity is used as an electromagnetic resilience technique in a triple modular redundant (TMR) communication channel that is subjected to a multiharmonic electromagnetic disturbance under semireverberant environments. This study is carried out in light of new electromagnetic interference (EMI) condition monitoring definitions, which provide a better insight into the actual state of the system. An explanation of the different fault mechanisms based on the new definitions is provided for a time diverse TMR system with a two-out-of-three majority voter and is compared with the previously used EMI condition monitoring definitions. The new definitions provide a better understanding on how to interpret the results of an EMI detector or an EMI corrector by keeping in consideration the safety and availability aspects of system. [ABSTRACT FROM AUTHOR]

A novel method to efficiently compute the interaction between two devices is proposed with the aim of accurately reproducing radiated immunity and emission tests in simulations. The technique allows an arbitrary relative position and orientation between the two devices. It relies on a single simulation (or measurement) of the radiation pattern of each device. To take rotation of the devices into account, a spherical harmonics decomposition is applied together with Wigner-D rotation matrices. The resulting procedure is practical, has a low computational cost, and shows good agreement with measurements and full-wave simulations. [ABSTRACT FROM AUTHOR]

In this article, for the first time, a power delivery network (PDN) noise absorber is applied to the power system and verified based on a power trace system. Among all the existing absorptive circuits, a low-pass reflectionless circuit is chosen as our PDN noise absorber due to its broadband characteristic. Since the speed of the signal becomes higher and higher nowadays, a millimeter distance of a power trace with the traditional reflective PDN noise suppression devices, such as decoupling capacitors (de-caps), may provide serious standing wave on it and seriously affect the system. The proposed PDN noise absorber, on the other hand, can absorb the PDN noises so that the standing wave on the power trace can be prevented. This makes power trace systems more stable and avoids significant power noises at some locations. A prototype using a PDN noise absorber was fabricated. The power integrity performance of this prototype was compared with two other cases, power trace only and power trace with a de-cap. Compared with the de-cap case at the designed frequency 750 MHz, a PDN noise absorber can reduce 40% maximum voltage ripple. On the other hand, noise coupling between the digital and radio frequency circuits has also been demonstrated and compared for those three different PDNs. It shows a 3.7-dB decrease in gain fluctuation for the PDN with power noise absorber compared with the de-cap case. According to these results, no matter from power integrity or noise coupling suppression viewpoint, PDN noise absorber can be a good candidate to make the power system more stable. [ABSTRACT FROM AUTHOR]

A novel harmonic balance surrogate-based technique to create fast and accurate behavioral models predicting, in the early design stage, the performance of nonlinear analog devices during immunity tests is presented. The obtained immunity model hides the real netlist, reduces the simulation time, and avoids expensive and time-consuming measurements after tape-out, while still providing high accuracy. The model can easily be integrated into a circuit simulator together with additional subcircuits, e.g., board and package models, as such allowing to efficiently reproduce complete immunity test setups during the early design stage and without disclosing any intellectual property. The novel method is validated by means of application to an industrial case study, being an automotive voltage regulator, clearly showing the technique’s capabilities and practical advantages. [ABSTRACT FROM PUBLISHER]

Measurement bandwidth of energy measurements are increasing to incorporate all the harmonics created by nonlinear loads and distributed generators making the measurement electronics complex and sensitive to electromagnetic interference. This article proposes to change the accuracy paradigm by focusing on fundamental active power and lower harmonics for energy metering, simplifying the electronics and making them robust against electromagnetic interference. Using the orthogonality of power flow via Parseval's theorem, a theoretical analysis, simulations, and measurements on power calculations using the fundamental active power are presented. It is shown that a perfect power measurement is achieved with a pure 50 Hz supply voltage, regardless of the nonlinear current. Even with the highest allowed harmonic distortion of the voltage and the current as listed in the international standards EN 50160 and IEC 61000-3-2, more than 97.5% of the active power is contained in the fundamental active power. Negligible active power is contained in the higher frequency components. This error margin falls within limits for electricity meters. Filtering the current with a basic low-pass filter can prevent the erroneous measurements that have appeared with static energy meters. In other words, it has been proven that negligible energy flows in the higher frequency components. [ABSTRACT FROM AUTHOR]

This article presents an innovative technique for the black-box modeling of the conductive emissions of switching circuits from external observations. The proposed methodology relies on the robust and elegant theory of periodically switched linear systems, providing the user with a tool for the generation of frequency-domain augmented linear time-invariant equivalents. The obtained models offer both a remarkable accuracy for different supply conditions and a deep understanding of the inherent switching mechanisms of this class of devices. The proposed framework also enables the derivation of a simplified enhanced Norton representation which outperforms the classical state-of-the-art models based on linear time-invariant approximations. Model parameters are computed via a blind procedure based only on two measurements. The feasibility and strength of the proposed approach are demonstrated on a dc–dc boost power converter and on a dc electrical motor via the prediction of their conducted disturbances. [ABSTRACT FROM AUTHOR]

The effect of multilayer stratified ground on the harmonic impedance of grounding systems is evaluated. To this aim, the mixed-potential integral equation is used. The method is general as it allows taking into account 1) stratified soil structure with any number of layers and 2) grounding electrodes with arbitrary shapes. Moreover, the method has no limitation in terms of the maximum working frequency. The impressed-current model is used as the excitation and the harmonic impedance is directly obtained from the method of moments matrix. This is in contrast with the conventional methods where the harmonic impedance is calculated from the integration of the electric field at ground surface. The cases of horizontal and vertical electrodes buried in soils with different layers are analyzed. The accuracy of the proposed approach is validated by comparing the results with those obtained by independent numerical methods. [ABSTRACT FROM PUBLISHER]

Characterization of unintended radiated emissions (URE) from electronic devices plays an important role in many research areas from electromagnetic interference to nonintrusive load monitoring to information system security. URE can provide insights for applications ranging from load disaggregation and energy efficiency to condition-based maintenance of equipment-based upon detected fault conditions. URE characterization often requires subject matter expertise to tailor transforms and feature extractors for the specific electrical devices of interest. We present a novel approach, named dimensionally aligned signal projection (DASP), for projecting aligned signal characteristics that are inherent to the physical implementation of many commercial electronic devices. These projections minimize the need for an intimate understanding of the underlying physical circuitry and significantly reduce the number of features required for signal classification. We present three possible DASP algorithms that leverage frequency harmonics, modulation alignments, and frequency peak spacings, along with a two-dimensional image manipulation method for statistical feature extraction. To demonstrate the ability of DASP to generate relevant features from URE, we measured the conducted URE from 14 residential electronic devices using a 2 MS/s collection system. A linear discriminant analysis classifier was trained using DASP generated features and was blind tested resulting in a greater than 90% classification accuracy for each of the DASP algorithms and an accuracy of 99.1% when DASP features are used in combination. Furthermore, we show that a rank reduced feature set of the combined DASP algorithms provides a 98.9% classification accuracy with only three features and outperforms a set of spectral features in terms of general classification as well as applicability across a broad number of devices. [ABSTRACT FROM AUTHOR]

Effects of transmit jitter on lossy clock channel are analyzed analytically by treating the 1010 input clock signal as a sinusoidal wave with a phase modulation that represents jitter. Jitter-to-amplitude-modulation transfer functions are derived for sinusoidal jitter, duty-cycle distortion (DCD), and random jitter (RJ) in terms of the signal transfer function or S-parameters. Input jitter is shown to induce amplitude modulation in the output signal as a result of channel dispersion, leading to voltage noise at the channel output. DCD- and RJ-induced voltage noises are found to scale uniquely with channel loss. To verify the theory, numerical simulations are performed on channels with different losses and at various data rates. The input clock signal is represented with a square wave, and the output signal is calculated by linear superposition of the channel step response. Theoretical and simulation results are found to be in excellent agreement. [ABSTRACT FROM AUTHOR]

An improved multiple scattering method is developed for an irregular plate pair where via pad/antipad radius is electrically small and the spacing between any two vias is relatively large so that the axially anisotropic parallel plate modes can be neglected. The plate-pair impedance matrix, widely used as an important parameter in power integrity analysis and also a critical part for via coupling in the intrinsic and the physics-based via models, is found to be related to the addition theorems of the zero-order axially isotropic propagating modes. As the impedance matrix of an irregular plate pair can be calculated by many analytical and numerical methods, the relationship between the plate-pair impedance matrix and the addition theorems of the zero-order axially isotropic propagating modes enables the handling of both the mutual coupling among vias and the reflection from plate-pair edges. Thus, the conventional multiple scattering method, restricted to either an infinitely large or a finite circular plate pair, can be extended to irregular plates for the via structures described earlier. The assumptions of the method are discussed and several numerical examples are provided to validate the proposed improved method. [ABSTRACT FROM AUTHOR]

It is well known that increasing the rise/fall time of a digital signal reduces the high-frequency spectral content, thereby enhancing the chances of meeting regulatory electromagnetic interference (EMI) requirements. Unlike the EMI regulations, most radio-frequency interference (RFI) issues in mobile devices are band limited. Given the growing concern regarding timing constraints of high-speed serial links, increasing the rise time cannot sufficiently suppress a specific harmonic that causes RFI. In this study, we demonstrate that a certain harmonic can be practically removed by making (not necessarily increasing) the rise time a multiple of the reciprocal of that harmonic frequency. [ABSTRACT FROM AUTHOR]