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Full-Text Articles in Engineering

Numerical Modeling Of Periodic Composite Media For Electromagnetic Shielding Application, Dagang Wu, Rui Qiang, Ji Chen, Ce Liu, Marina Koledintseva, James L. Drewniak, Bruce Archambeault Jul 2016

Numerical Modeling Of Periodic Composite Media For Electromagnetic Shielding Application, Dagang Wu, Rui Qiang, Ji Chen, Ce Liu, Marina Koledintseva, James L. Drewniak, Bruce Archambeault

James K. Wu, M.D.

This paper describes a methodology to extract effective electrical properties for periodic composite medium. The extraction algorithm is based on a periodic finite-difference time-domain (FDTD) method. The results are compared with conventional mixing theories and 3D Fourier series expansion methods. Two results show satisfactory agreement. With the extracted effective permittivity and conductivity, one can readily use these parameters to study electrical properties of composite materials with arbitrary micro-geometry and the shielding effects of using composite materials.


Representation Of Permittivity For Multiphase Dielectric Mixtures In Fdtd Modeling, Marina Koledintseva, J. Wu, H. Zhang, James L. Drewniak, Konstantin Rozanov Jul 2016

Representation Of Permittivity For Multiphase Dielectric Mixtures In Fdtd Modeling, Marina Koledintseva, J. Wu, H. Zhang, James L. Drewniak, Konstantin Rozanov

James K. Wu, M.D.

A simple method of approximating frequency characteristics of composites in a form convenient for time-domain numerical modeling is proposed. The frequency characteristics can be obtained from experiment or calculations based on the Maxwell Garnett mixing formalism. The resultant frequency characteristic might be of a complex shape corresponding to a combination of a number of absorption peaks. The approximation is made by a series of Debye-like terms using a genetic algorithm (GA). This leads to the necessity of taking a number of terms in the approximating series. Every term corresponds to its pole, i.e., the frequency where the maximum loss occurs. …


Standby Leakage Power Reduction Technique For Nanoscale Cmos Vlsi Systems, Heungjun Jeon, Yong-Bin Kim, Minsu Choi May 2010

Standby Leakage Power Reduction Technique For Nanoscale Cmos Vlsi Systems, Heungjun Jeon, Yong-Bin Kim, Minsu Choi

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a novel low-power design technique is proposed to minimize the standby leakage power in nanoscale CMOS very large scale integration (VLSI) systems by generating the adaptive optimal reverse body-bias voltage. The adaptive optimal body-bias voltage is generated from the proposed leakage monitoring circuit, which compares the subthreshold current (ISUB) and the band-to-band tunneling (BTBT) current (IBTBT). The proposed circuit was simulated in HSPICE using 32-nm bulk CMOS technology and evaluated using ISCAS85 benchmark circuits at different operating temperatures (ranging from 25°C to 100°C). Analysis of the results shows a maximum of 551 and …


Novel And Simple High-Frequency Single-Port Vector Network Analyzer, Mohamed A. Abou-Khousa, Mark A. Baumgartner, Sergey Kharkovsky, R. Zoughi Mar 2010

Novel And Simple High-Frequency Single-Port Vector Network Analyzer, Mohamed A. Abou-Khousa, Mark A. Baumgartner, Sergey Kharkovsky, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Portable, accurate, and relatively inexpensive high-frequency vector network analyzers (VNAs) have great utility for a wide range of applications, encompassing microwave circuit characterization, reflectometry, imaging, material characterization, and nondestructive testing to name a few. To meet the rising demand for VNAs possessing the aforementioned attributes, we present a novel and simple VNA design based on a standing-wave probing device and an electronically controllable phase shifter. The phase shifter is inserted between a device under test (DUT) and a standing-wave probing device. The complex reflection coefficient of the DUT is then obtained from multiple standing-wave voltage measurements taken for several different …


Cavities' Identification Algorithm For Power Integrity Analysis Of Complex Boards, S. Cicerone, Antonio Orlandi, Bruce Archambeault, Samuel R. Connor, Jun Fan, James L. Drewniak Jan 2009

Cavities' Identification Algorithm For Power Integrity Analysis Of Complex Boards, S. Cicerone, Antonio Orlandi, Bruce Archambeault, Samuel R. Connor, Jun Fan, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

The analysis and the design of the Power Delivery Network (PDN) is crucial in the real world of high-speed and high-performance on-board systems. In this context, the Cavity Model (where facing portions of power bus are considered electromagnetic resonant cavities) can be used to study the generation and propagation of noise. Given a real-world board's layout, one of the primary requirements for the application of this technique is the geometrical identification of all the cavities and their connectivity. This paper is focused on the fully automatic generation of this geometrical dataset as part of an integrated tool for the analysis …


Predictive Modeling Of The Effects Of Skew And Imbalance On Radiated Emi From Cables, J. Chen, James L. Drewniak, Richard E. Dubroff, James L. Knighten, Jun Fan, J. Flavin Jul 2007

Predictive Modeling Of The Effects Of Skew And Imbalance On Radiated Emi From Cables, J. Chen, James L. Drewniak, Richard E. Dubroff, James L. Knighten, Jun Fan, J. Flavin

Electrical and Computer Engineering Faculty Research & Creative Works

This paper provides an approach for predicting the effects of skew and imbalance on radiated emission of cables inside a commercial 19-inch rack-based cabinet. Scattering parameters (S-parameters) for two sets of cable assembly are measured with a four-port vector network analyzer (VNA) and converted into mixed mode S-parameters. Time-domain input signals with different slew rates and different amount of skew are transferred into frequency-domain using fast Fourier transform (FFT). The spectra of radiation emission associated with different inputs are then estimated.


Numerical Modeling Of Periodic Composite Media For Electromagnetic Shielding Application, Dagang Wu, Rui Qiang, Ji Chen, Ce Liu, Marina Koledintseva, James L. Drewniak, Bruce Archambeault Jul 2007

Numerical Modeling Of Periodic Composite Media For Electromagnetic Shielding Application, Dagang Wu, Rui Qiang, Ji Chen, Ce Liu, Marina Koledintseva, James L. Drewniak, Bruce Archambeault

Electrical and Computer Engineering Faculty Research & Creative Works

This paper describes a methodology to extract effective electrical properties for periodic composite medium. The extraction algorithm is based on a periodic finite-difference time-domain (FDTD) method. The results are compared with conventional mixing theories and 3D Fourier series expansion methods. Two results show satisfactory agreement. With the extracted effective permittivity and conductivity, one can readily use these parameters to study electrical properties of composite materials with arbitrary micro-geometry and the shielding effects of using composite materials.


Representation Of Permittivity For Multiphase Dielectric Mixtures In Fdtd Modeling, Marina Koledintseva, J. Wu, H. Zhang, James L. Drewniak, Konstantin Rozanov Aug 2004

Representation Of Permittivity For Multiphase Dielectric Mixtures In Fdtd Modeling, Marina Koledintseva, J. Wu, H. Zhang, James L. Drewniak, Konstantin Rozanov

Electrical and Computer Engineering Faculty Research & Creative Works

A simple method of approximating frequency characteristics of composites in a form convenient for time-domain numerical modeling is proposed. The frequency characteristics can be obtained from experiment or calculations based on the Maxwell Garnett mixing formalism. The resultant frequency characteristic might be of a complex shape corresponding to a combination of a number of absorption peaks. The approximation is made by a series of Debye-like terms using a genetic algorithm (GA). This leads to the necessity of taking a number of terms in the approximating series. Every term corresponds to its pole, i.e., the frequency where the maximum loss occurs. …


Memory Dimm Dc Power Distribution Analysis And Design, Jingkun Mao, Chen Wang, Giuseppe Selli, Bruce Archambeault, James L. Drewniak Aug 2003

Memory Dimm Dc Power Distribution Analysis And Design, Jingkun Mao, Chen Wang, Giuseppe Selli, Bruce Archambeault, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

DC power bus design is critical in meeting signal integrity (SI) and electromagnetic compatibility (EMC) requirements. A suitable modeling tool is beneficial to evaluate power bus design and develop design guidelines. This paper discusses difficulties met in evaluating the power distribution design on a dual inline memory module (DIMM) board, such as a power bus with arbitrary shape, parasitic inductance associated with vias, and so on. Moreover, some solutions are given in this paper. A simple cavity model with a segmentation method was employed to model a power bus with irregular shapes. The partial element equivalent circuit (PEEC) technique was …


Emi Resulting From A Signal Via Transition Through Dc Power Bus-Effectiveness Of Focal Smt Decoupling, Wei Cui, Xiaoning Ye, Bruce Archambeault, Doug White, Min Li, James L. Drewniak May 2000

Emi Resulting From A Signal Via Transition Through Dc Power Bus-Effectiveness Of Focal Smt Decoupling, Wei Cui, Xiaoning Ye, Bruce Archambeault, Doug White, Min Li, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

Signal vias are commonly used in multilayer printed circuit board (PCB) design. For a signal via transitioning through the internal power and ground planes, the return current has to jump from one reference plane to another reference plane. The discontinuity of the return current at the via excites the power and ground planes, and results in power bus noise, and can produce an EMI problem as well. Numerical methods, such as finite-difference time-domain (FDTD), moment methods (MoM), and partial element equivalent circuit (PEEC), were employed herein to study this problem. The modeled results were supported by the measurements. In addition, …


Modeling Emi Resulting From A Signal Via Transition Through Power/Ground Layers, Wei Cui, Xiaoning Ye, Bruce Archambeault, Doug White, Min Li, James L. Drewniak Mar 2000

Modeling Emi Resulting From A Signal Via Transition Through Power/Ground Layers, Wei Cui, Xiaoning Ye, Bruce Archambeault, Doug White, Min Li, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

Signal transitioning through layers on vias are very common in multi-layer printed circuit board (PCB) design. For a signal via transitioning through the internal power and ground planes, the return current must switch from one reference plane to another reference plane. The discontinuity of the return current at the via excites the power and ground planes, and results in noise on the power bus that can lead to signal integrity, as well as EMI problems. Numerical methods, such as the finite-difference time-domain (FDTD), Moment of Methods (MoM), and partial element equivalent circuit (PEEC) method, were employed herein to study this …


Modeling Power Bus Decoupling On Multilayer Printed Circuit Boards, James L. Drewniak, Todd H. Hubing, Thomas Van Doren, P. Baudendistal Aug 1994

Modeling Power Bus Decoupling On Multilayer Printed Circuit Boards, James L. Drewniak, Todd H. Hubing, Thomas Van Doren, P. Baudendistal

Electrical and Computer Engineering Faculty Research & Creative Works

Power bus decoupling designs on multilayer printed circuit boards must adequately account for the power bus interplane capacitance and its consequences for the design. Lumped element models for a power bus on a multilayer printed circuit board where an appreciable or entire portion of a layer is devoted to power and ground have been developed. The models are applicable below the distributed resonances of the board. Analytical, circuit simulation, and experimental studies have been conducted to test the models, investigate the effects of the distributed interplane capacitance of the power bus, and the effect of interconnect inductance associated with surface-mount …


Analysis Of Radiation From An Open-Ended Coaxial Line Into Stratified Dielectrics, Sasan Bakhtiari, Stoyan I. Ganchev, R. Zoughi Jul 1994

Analysis Of Radiation From An Open-Ended Coaxial Line Into Stratified Dielectrics, Sasan Bakhtiari, Stoyan I. Ganchev, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Radiation from an open-ended coaxial transmission line into an N-layer dielectric medium is studied in application to nondestructive evaluation of materials. Explicit formulations for two cases of layered media, one terminated into an infinite half-space and the other into a conducting sheet are addressed in general form. In the theoretical derivations it is assumed that only the fundamental TEM mode propagates inside the coaxial line. The terminating admittance of the line is then formulated using the continuity of the power flow across the aperture. The admittance expressions for specific cases of two-layer dielectric composite with generally lossy dielectric properties, and …


Microwave Noncontact Examination Of Disbond And Thickness Variation In Stratified Composite Media, Sasan Bakhtiari, Nasser N. Qaddoumi, Stoyan I. Ganchev, R. Zoughi Mar 1994

Microwave Noncontact Examination Of Disbond And Thickness Variation In Stratified Composite Media, Sasan Bakhtiari, Nasser N. Qaddoumi, Stoyan I. Ganchev, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Numerical and experimental results of a microwave noncontact, nondestructive detection and evaluation of disbonds and thickness variations in stratified composite media are presented. The aperture admittance characteristics of a flange mounted rectangular waveguide radiating into a layered, generally lossy dielectric media backed or unbacked by a conducting sheet is modeled. The theoretical implementation is based on a Fourier transform boundary matching technique to construct the field components in each medium, coupled with a stationary form of the terminating aperture admittance of the waveguide. The model can serve as a reliable test bed for real-time examination of layered composite media. Experimental …