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Articles 6511 - 6540 of 36833

Full-Text Articles in Engineering

Clock Duty Cycle Tuning For Desense Mitigation In Modulation -Involved Cases, Shengxuan Xia, Jun Fan, Chulsoon Hwang Jan 2022

Clock Duty Cycle Tuning For Desense Mitigation In Modulation -Involved Cases, Shengxuan Xia, Jun Fan, Chulsoon Hwang

Electrical and Computer Engineering Faculty Research & Creative Works

Nowadays consumers' electronic devices are highly integrated, and modules and integrated circuits (ICs) are usually placed close to each other due to the compact size. The modules and ICs may interfere with the radio frequency (RF) antennas and cause desense issues. In recent years, desense caused by direct coupling from the noise sources to the victim RF antennas has been well studied. However, more complicated mechanisms such as modulations between transmitting signals and low-frequency clock or data signals can also result in desense problems, especially in frequency divide duplex (FDD) applications. Typical solutions to desense problems will focus on suppressing …

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Dielectric Loss Tangent Extraction Using Two Single-Ended Striplines Of Different Width, Jiangshuai Li, Yuanzhuo Liu, Liang Liu, Shengxuan Xia, Scott Hinaga, Victor Khilkevich Jan 2022

Dielectric Loss Tangent Extraction Using Two Single-Ended Striplines Of Different Width, Jiangshuai Li, Yuanzhuo Liu, Liang Liu, Shengxuan Xia, Scott Hinaga, Victor Khilkevich

Electrical and Computer Engineering Faculty Research & Creative Works

Frequency-dependent electrical properties of dielectric materials are one of the most important factors for high-speed signal integrity design. Recently a method of accurately measuring the dielectric loss tangent ($\tan \delta$) of differential lines was proposed. By taking into account the ratio between the differential and common mode per-unit-length resistances the surface roughness contribution to the total loss is eliminated and dielectric parameters can be determined. In this article a similar method is applied to a combination of two single-ended lines. To evaluate the accuracy of the extraction, the impact of the de-embedding errors was investigated, which allows to optimize the …

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A Segmentation Strategy For Structures With Common Mode Coupling, James Hunter, Shengxuan Xia, Aaron Harmon, Mohamed Z.M. Hamdalla, Ahmed M. Hassan, Victor Khilkevich, Daryl G. Beetner Jan 2022

A Segmentation Strategy For Structures With Common Mode Coupling, James Hunter, Shengxuan Xia, Aaron Harmon, Mohamed Z.M. Hamdalla, Ahmed M. Hassan, Victor Khilkevich, Daryl G. Beetner

Electrical and Computer Engineering Faculty Research & Creative Works

The level of electromagnetic coupling to electronic devices can vary widely from one device to another. When considering the induced voltage from an incoming plane wave on printed circuit boards (PCBs) and their attached cable harnesses, there is significant variety in the configuration of the devices that could be seen. This encourages the use of segmentation, so that the components of these devices (PCBs, connectors, and harnesses) can be modeled separately to alleviate simulation burden. This allows for a more flexible model and a 'toolbox' to construct devices with. The goal of this work is to use segmentation to model …

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High Permittivity Anisotropic 3d Printed Material, Aaron Harmon, Victor Khilkevich, Kristen M. Donnell Jan 2022

High Permittivity Anisotropic 3d Printed Material, Aaron Harmon, Victor Khilkevich, Kristen M. Donnell

Electrical and Computer Engineering Faculty Research & Creative Works

In this work, the diagonal elements of the permittivity matrix for dielectric samples, 3D printed with a carbon fiber-loaded material (XT-CF20), are measured for frequencies within the range of 1 MHz to 18 GHz. These permittivity measurements demonstrated a strong anisotropy, indicating that the electromagnetic properties of the CF20 material depend on the infill method used to print. The importance of understanding the anisotropy for microwave device design is demonstrated via a dielectric-loaded cavity resonator application.

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Practical Fixture Design For Passive Intermodulation Tests For Flexible Metallic Contacts, Shengxuan Xia, Yuchu He, Yansheng Wang, Hanfeng Wang, George Mankaruse, Danny Chan, Haicheng Zhou, Warren Lee, Nicholas Mcdonnell, Chulsoon Hwang Jan 2022

Practical Fixture Design For Passive Intermodulation Tests For Flexible Metallic Contacts, Shengxuan Xia, Yuchu He, Yansheng Wang, Hanfeng Wang, George Mankaruse, Danny Chan, Haicheng Zhou, Warren Lee, Nicholas Mcdonnell, Chulsoon Hwang

Electrical and Computer Engineering Faculty Research & Creative Works

Passive intermodulation (PIM) commonly exists in non-ideal metallic contacts. Since PIM typically represents an extremely low level of nonlinearity, it has not drawn enough attention over the years except for extremely high-power applications such as base stations. However, in recent years, the study on PIM has become essential in universally used consumer electronics design because of the higher requirement on the radio frequency (RF) sensitivity of wireless communications. The metal contacts caused PIM can create the sideband spectrum to interfere with the receiving band in the frequency divide duplex (FDD) mode. Therefore, the study on PIM for the frequently used …

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Peec-Based On-Chip Pdn Impedance Modeling Using Layered Green's Function, Chaofeng Li, Biyao Zhao, Bo Pu, Xu Wang, Donghyun Kim, Jun Fan Jan 2022

Peec-Based On-Chip Pdn Impedance Modeling Using Layered Green's Function, Chaofeng Li, Biyao Zhao, Bo Pu, Xu Wang, Donghyun Kim, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents an impedance model of on-chip power distribution network (PDN), which is an efficient criterion for estimating simultaneous switching noises (SSNs) on 3-D integrated circuit (IC). The impedance of on-chip PDN, including the effect of silicon substrate, is accurately modeled based on partial element equivalent circuit (PEEC) and layered Green's function (LGF). The equivalent circuit model of PDN is extracted based on the physical dimensions and electrical material characteristic of PDN at first. And then the LGF is used to consider the effect of silicon substrate for improving the accuracy of on-chip PDN impedance model. The effectiveness of …

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Analysis Of Switching Voltage Regulator Noise Coupling To A High-Speed Signal, Junho Joo, Soumya Singh, P. K. Seema, Chulsoon Hwang, Bhyrav Mutnury, James L. Drewniak Jan 2022

Analysis Of Switching Voltage Regulator Noise Coupling To A High-Speed Signal, Junho Joo, Soumya Singh, P. K. Seema, Chulsoon Hwang, Bhyrav Mutnury, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a real-world signal and power integrity problem due to the switching noise of buck converter IC coupling to a high-speed signal line in a server system is studied. The rapid switching field effect transistors (FETs) of the voltage regulator module (VRM) are the main source of the performance degradation on the nearby signal lines. A simplified mock-up simulation setup is proposed based on the actual board design to investigate the coupling mechanism of the VRM noise. The mechanism of the switching noise coupling is explained with the phenomenon of capacitive and inductive coupling. Based on this finding, …

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3d Printed Multilayer Microwave Absorber, Wei Zhang, Rui Mi, Victor Khilkevich Jan 2022

3d Printed Multilayer Microwave Absorber, Wei Zhang, Rui Mi, Victor Khilkevich

Electrical and Computer Engineering Faculty Research & Creative Works

This paper explores the possibility to create 3D printed multilayer electromagnetic absorbers. The proposed design is similar to the thin-film filters used in optics and consists of interleaving high and low permittivity layers. Based on transmission line theory, the multilayer absorber can be designed in a circuit simulator. Analytical equations, circuit simulations, and measurements are used to analyze and validate the designed absorber. Multilayer absorbers based on 3D printed material can be an inexpensive option for engineering usage with great design flexibility and fast fabrication.

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A Practical Simulation Flow For Singing Capacitor Based Acoustic Noise Analysis, Xin Yan, Songping Wu, Mingfeng Xue, Chi Kin Benjamin Leung, Daryl G. Beetner, Jianmin Zhang Jan 2022

A Practical Simulation Flow For Singing Capacitor Based Acoustic Noise Analysis, Xin Yan, Songping Wu, Mingfeng Xue, Chi Kin Benjamin Leung, Daryl G. Beetner, Jianmin Zhang

Electrical and Computer Engineering Faculty Research & Creative Works

Multilayer ceramic capacitors (MLCCs) are widely used in modern electronics. Due to the piezoelectric effect of the ceramic material, however, MLCCs subjected to electrical noise may vibrate and generate acoustic noise, as 'singing'. Acoustic noise can be annoying for users, especially within mobile devices, so it becomes important to perform acoustic noise analysis before a product is released. In this paper, a practical simulation flow for singing capacitor based acoustic noise is presented. The simulation flow and analysis method are developed on Ansys Sherlock and Mechanical. In Ansys Sherlock, local library and Approved Vendor List (AVL) files were used to …

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Predicting Radiated Emissions From A Complex Transportation System Wiring Harness, Fuwei Ma, Ruijie He, Sameer Walunj, Tamar Makharashvili, Chulsoon Hwang, Daryl G. Beetner, Brian Booth, Kerry Martin Jan 2022

Predicting Radiated Emissions From A Complex Transportation System Wiring Harness, Fuwei Ma, Ruijie He, Sameer Walunj, Tamar Makharashvili, Chulsoon Hwang, Daryl G. Beetner, Brian Booth, Kerry Martin

Electrical and Computer Engineering Faculty Research & Creative Works

Low frequency radiated emissions problems are often caused by common mode currents flowing on wiring harnesses. The ability to predict radiated emissions problems early in the design process can save both time and money and result in a better product. Methods have previously been reported for rapidly characterizing common-mode sources driving a harness and then using these equivalent sources to predict radiated emissions. These methods are extended in the following paper to predict radiated emissions from a complex 32-wire harness bundle connected to an engine control unit. Rapid experimental characterization of the common mode sources is enabled using an equivalent …

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Optimizing The Placement Of Non-Functional Pads On Signal Vias Using Multiple Reflection Analysis, Muqi Ouyang, Kevin Cai, Chaofeng Li, Anna Gao, Felen Fu, Hannah Bian, Bidyut Sen, Donghyun Kim Jan 2022

Optimizing The Placement Of Non-Functional Pads On Signal Vias Using Multiple Reflection Analysis, Muqi Ouyang, Kevin Cai, Chaofeng Li, Anna Gao, Felen Fu, Hannah Bian, Bidyut Sen, Donghyun Kim

Electrical and Computer Engineering Faculty Research & Creative Works

In this study, the effects of using non-functional pads to optimize the performance of high-speed signal vias are investigated based on multiple reflection analysis. The non-functional pads on signal vias introduce more capacitive coupling and are possible to improve the response of the via structure if the original via has relatively larger impedance compared to the system reference impedance. The effectiveness of the non-functional pad optimization is validated through a numerical example, and the eye diagram of the via structure without and with non-functional pads are compared. The eye opening becomes 5.4 times larger after the via optimization using non-functional …

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A Methodical Approach For Pcb Pdn Decoupling Minimizing Overdesign With Genetic Algorithm Optimization, F. De Paulis, Y. Ding, M. Cocchini, Chulsoon Hwang, S. Connor, M. Doyle, S. Scearce, W. D. Becker, Albert E. Ruehli, James L. Drewniak Jan 2022

A Methodical Approach For Pcb Pdn Decoupling Minimizing Overdesign With Genetic Algorithm Optimization, F. De Paulis, Y. Ding, M. Cocchini, Chulsoon Hwang, S. Connor, M. Doyle, S. Scearce, W. D. Becker, Albert E. Ruehli, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

An optimization routine is applied for the decoupling capacitor placement on Power Distribution Networks to identify the limit beyond which the placement of additional decaps is no longer effective, thus leading to wasting layout area and components, and to a cost increase. A specific test example from a real design is used together with the required target impedance and frequency band of interest for the PDN design. The effectiveness of the decap placement while selecting different layers of the stack-up, and while moving the upper limit of the PDN design band is analyzed. Such analysis leads to helpful insights based …

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Physics-Based Modeling For Determining Transient Current Flow In Multi-Layer Pcb Pi Designs, Yifan Ding, Matthew S. Doyle, Samuel Connor, Dale Becker, James L. Drewniak Jan 2022

Physics-Based Modeling For Determining Transient Current Flow In Multi-Layer Pcb Pi Designs, Yifan Ding, Matthew S. Doyle, Samuel Connor, Dale Becker, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

A physics-based modeling methodology for determining the transient current flow path in multi-layer PI designs is given in this paper using a commercial board with a complicated structure as an example. Board structure analysis is done first to provide a physical basis of post-layout analytical and equivalent circuit modeling. A match of the PDN impedance between commercial tool simulation, post-layout analytical calculation, and the physics-based equivalent circuit modeling was achieved to support the model for the transient simulation. By analyzing the current response in all the vias, a clear representation of transient current flow across all via segments can be …

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Identifying Sources Of Conducted Emissions By Measuring The Coherence Function, Xin Yan, Fuwei Ma, Wei Zhang, Kaustav Ghosh, Sameer Walunj, Philippe Sochoux, Victor Khilkevich Jan 2022

Identifying Sources Of Conducted Emissions By Measuring The Coherence Function, Xin Yan, Fuwei Ma, Wei Zhang, Kaustav Ghosh, Sameer Walunj, Philippe Sochoux, Victor Khilkevich

Electrical and Computer Engineering Faculty Research & Creative Works

Conducted emissions (CE) is one of the electromagnetic interference (EMI) issues that pose serious compliance problems for electronic devices. For a system with several sources, estimating the contribution of each source to conducted emission at different frequencies can be a challenge. In this article, a coherence function-based signal separation method is presented and validated on two commercial power supply units (PSU). The noise generated by the PSU and measured at the line impedance stabilization network (LISN) port contains two predominantly uncorrelated signals associated with the power factor correction (PFC) and H -bridge/rectifier circuits with unknown contributions at different frequencies. Two …

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Two-Dimensional In-Plane Strain Fss-Based Sensor, Mahboobeh Mahmoodi, Kristen M. Donnell Jan 2022

Two-Dimensional In-Plane Strain Fss-Based Sensor, Mahboobeh Mahmoodi, Kristen M. Donnell

Electrical and Computer Engineering Faculty Research & Creative Works

Frequency selective surface (FSS) based sensors have found application as sensors in the last decade. In this paper, a new sensor design is proposed for two-dimensional in-plane strain sensing. The unit cell of the FSS-based sensor includes two slot dipoles, oriented normal to one another and each with different dimensions, to create two unique resonant frequencies when interrogated with an incident electric field normal to the direction of measured strain. In this way, 2D strain can be characterized concurrently and independently. The error due to strain orthogonal to the direction of interest, along with the error due to the presence …

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A Meander Line-Based Frequency Selective Surface For Strain Sensing, Swathi Muthyala Ramesh, Kristen M. Donnell Jan 2022

A Meander Line-Based Frequency Selective Surface For Strain Sensing, Swathi Muthyala Ramesh, Kristen M. Donnell

Electrical and Computer Engineering Faculty Research & Creative Works

Frequency selective surfaces (FSSs) are periodic arrays of conductive elements that have distinct reflection and transmission responses. In this work, an FSS sensor designed to operate in Ka-band to measure a wide range of uni-directional strain using a meander line-based unit cell is presented. Specifically, the proposed unit cell of the sensor consists of a convoluted meander line geometry designed on a thin dielectric substrate. Strain sensing is achieved by monitoring the change in the resonant frequency of the FSS when under strain that is parallel to an interrogating signal linearly polarized and aligned with the convoluted dimension of the …

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Practical Fss-Based Sensor Sensitivity, Mahboobeh Mahmoodi, Kristen M. Donnell Jan 2022

Practical Fss-Based Sensor Sensitivity, Mahboobeh Mahmoodi, Kristen M. Donnell

Electrical and Computer Engineering Faculty Research & Creative Works

Frequency selective surfaces are a periodic array of unit cells that, when illuminated externally, have a specific frequency response that depends on element geometry, spacing, and substrate properties. Theoretically, FSS is assumed as an infinite array of unit cells with a plane wave excitation. However, in practice, an FSS is finite and hence, due to edge effects, the limited number of unit cells, and non-uniform illumination, the response will deviate from the theoretical. As it relates to FSS-based sensing in particular, a localized illumination is often used in order to improve the sensing resolution. However, due to the aforementioned factors, …

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Influence Of Conformal Coatings On The Emc Performance Of A Printed Circuit Board, Haran Manoharan, Ruijie He, Fuwei Ma, Daryl G. Beetner, Brian Booth, Kerry Martin Jan 2022

Influence Of Conformal Coatings On The Emc Performance Of A Printed Circuit Board, Haran Manoharan, Ruijie He, Fuwei Ma, Daryl G. Beetner, Brian Booth, Kerry Martin

Electrical and Computer Engineering Faculty Research & Creative Works

Conformal coatings are often applied to printed circuit boards to protect the board and its components from environmental factors like moisture, chemicals, and vibration. The impact of a conformal coating on crosstalk and radiated emissions was studied in the following paper. Two coating materials were characterized in terms of their permittivity and permeability. The impact of the conformal coating was evaluated based on the crosstalk between microstrip traces, the radiated emissions from a switch-mode power supply (SMPS), and on coupling from an EMI filter to nearby components. The coatings increased crosstalk between microstrip traces by up to 5 ~ 6 …

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Modeling Of Rf Interference Caused By Solid-State Drive Noise, Junho Joo, Woncheol Song, Taelim Song, Sunkyu Kong, Jungcheol Lim, Inmyung Song, Jongjoo Lee, Chulsoon Hwang Jan 2022

Modeling Of Rf Interference Caused By Solid-State Drive Noise, Junho Joo, Woncheol Song, Taelim Song, Sunkyu Kong, Jungcheol Lim, Inmyung Song, Jongjoo Lee, Chulsoon Hwang

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, modeling of RFI problem caused by a solid-state drive (SSD) in a laptop is proposed. Two noise sources (one outside and one inside a cavity) in the SSD are reconstructed as dipole moments with magnitude-only near-field scanning data. The dipole moment inside a cavity is then replaced by a Huygens' box covering four side surfaces of the cavity using a numerical simulation. The noise voltage at an RF antenna port is calculated by combining the two reconstructed noise sources with measured transfer functions. The model is successfully validated through a comparison of the calculation with measurement results.

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Insertion Loss Reduction Using Rounded Corners To Mitigate Surface Roughness Effect In Pcb Transmission Lines, Yuandong Guo, Donghyun Kim, Yuanzhuo Liu, Xiaoning Ye, Jimmy Hsu, Jun Fan Jan 2022

Insertion Loss Reduction Using Rounded Corners To Mitigate Surface Roughness Effect In Pcb Transmission Lines, Yuandong Guo, Donghyun Kim, Yuanzhuo Liu, Xiaoning Ye, Jimmy Hsu, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

Signal integrity (SI) can be interpreted as a measure of the distortion of the incident pulse, which is attributed to various contributors, e.g., inter-symbol interference (ISI), crosstalk, jitter, etc. The channel insertion loss is generally the most critical concern in SI designs, since it determines the working bandwidth of a high-speed channel, and the bandlimited channels are known as the root cause of ISI. At the tens of Gigabit rates in use today, PCB transmission lines may have appreciable losses, which can be divided into frequency-dependent dielectric loss and conductor loss, and noticeable amount of losses can be generated at …

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Fixture Design For Parasitic Capacitances Of Mosfets For Emi Applications, Anfeng Huang, Hanyu Zhang, Li Du, Cheung Wei Lam, Chulsoon Hwang Jan 2022

Fixture Design For Parasitic Capacitances Of Mosfets For Emi Applications, Anfeng Huang, Hanyu Zhang, Li Du, Cheung Wei Lam, Chulsoon Hwang

Electrical and Computer Engineering Faculty Research & Creative Works

Due to the fast-switching nature of modern power converters, up to hundreds of MHz of common-mode noise can easily be generated. The characterization of switching components, e.g., Si MOSFETs, is essential for noise reduction. However, limited by the bandwidth of instruments, the voltage-dependent capacitances of high voltage MOSFETs are typically characterized at approximately 1 MHz, which is insufficient for EMI applications. In this paper, the measurement method and the test fixtures are presented. The measurement bandwidth is pushed to 30 MHz and higher, and frequency-dependent capacitances of a MOSFET are observed through measurements.

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De-Embedding For Coupled Three-Port Devices, Yuandong Guo, Bo Pu, Donghyun Kim, Jun Fan Jan 2022

De-Embedding For Coupled Three-Port Devices, Yuandong Guo, Bo Pu, Donghyun Kim, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

In many applications, the device under test (DUT) is embedded into a test setup. Various de-embedding techniques have been proposed to expose the real electrical behaviors of a DUT, e.g., the traditional thru-reflect-line and short-open-load-thru algorithms, where the T-matrix and its inverse form are adopted in the mathematical process. In the fields of radiofrequency and electromagnetic compatibility, a DUT may have three coupled ports, and the symmetry in the associated S-matrix breaks down, because the numbers of entry and exist ports are not equal, which results in a non-square T-matrix based upon the definitions. Given that the inverse expression of …

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Concurrent Learning-Based Neuro-Adaptive Robust Tracking Control Of Wheeled Mobile Robot: An Event-Triggered Design, Krishanu Nath, Manas Kumar Bera, Sarangapani Jagannathan Jan 2022

Concurrent Learning-Based Neuro-Adaptive Robust Tracking Control Of Wheeled Mobile Robot: An Event-Triggered Design, Krishanu Nath, Manas Kumar Bera, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, an event-based neuro-adaptive robust tracking controller for a perturbed and networked differential drive mobile robot (DMR) is designed with concurrent learning. A radial basis function neural network, which approximates an unknown perturbation, is used to design an adaptive sliding mode controller (SMC). The RBFNN weights and SMC parameters are estimated online using an adaptive tuning law to ensure performance with reduced chattering. To improve the convergence of RBFNN weight estimation error, a concurrent learning-based adaptive law is derived, which uses measured online and recorded data. Further, a suitable triggering condition is designed to achieve a reduced number …

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I2Mtc 2021 Special Issue In Ieee Transactions On Instrumentation And Measurement, Pawel Niewczas, Kristen M. Donnell, Melanie Ooi Jan 2022

I2Mtc 2021 Special Issue In Ieee Transactions On Instrumentation And Measurement, Pawel Niewczas, Kristen M. Donnell, Melanie Ooi

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

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An Energy-Efficient Internet Of Things Relaying System For Delay-Constrained Applications, Abdullah M. Almasoud, Ahmad Alsharoa, Daji Qiao, Ahmed E. Kamal Jan 2022

An Energy-Efficient Internet Of Things Relaying System For Delay-Constrained Applications, Abdullah M. Almasoud, Ahmad Alsharoa, Daji Qiao, Ahmed E. Kamal

Electrical and Computer Engineering Faculty Research & Creative Works

The emerging Internet-of-things (IoT) systems contain a large number of small wireless devices with limited energy, communication, and computational capabilities. In such systems, a helping station located between the IoT devices and backhaul servers can be deployed to broadcast the IoT devices to the backhaul networks. This paper investigates a hybrid energy-efficient framework using multiple energy harvested relays with data buffering capabilities. The relays are powered by a hybrid energy supply consisting of a traditional electric grid and renewable energy grid. We propose an energy efficient novel approach aiming to support the wireless uplink transmission from IoT devices to backhaul …

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Pulsed-Active Microwave Thermography, Logan M. Wilcox, Mathias Bonmarin, Kristen M. Donnell Jan 2022

Pulsed-Active Microwave Thermography, Logan M. Wilcox, Mathias Bonmarin, Kristen M. Donnell

Electrical and Computer Engineering Faculty Research & Creative Works

Active microwave thermography (AMT) is a thermographic nondestructive testing and evaluation technique that utilizes an electromagnetic-based excitation with a subsequent infrared measurement of the surface thermal profile of the material or structure of interest. AMT has been successfully applied to several aerospace and civil infrastructure applications. This work seeks to expand the performance of AMT by incorporating a signal processing technique common to traditional (flash-lamp) thermography, referred to as pulsed thermography (PT). PT operates on the premise of a pulsed excitation, as opposed to a constant or step excitation (ST) over a given time-period that is typical to traditional active …

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Generation Expansion Planning Considering Discrete Storage Model And Renewable Energy Uncertainty: A Bi-Interval Optimization Approach, Siyuan Wang, Guangchao Geng, Qy Jiang, Rui Bo Jan 2022

Generation Expansion Planning Considering Discrete Storage Model And Renewable Energy Uncertainty: A Bi-Interval Optimization Approach, Siyuan Wang, Guangchao Geng, Qy Jiang, Rui Bo

Electrical and Computer Engineering Faculty Research & Creative Works

Both discrete storage model (DSM) and continuous storage model (CSM) have been used in the power system planning literature. In this work, we conduct a sizing-error analysis for the use of CSM in generation expansion planning (GEP), which shows more reasonable storage sizing decisions are offered by the DSM in comparison to the CSM. However, when the DSM is considered in the context of interval optimization, the discrete status variables in mutually exclusive constraints and the strong temporal coupling in state-of-charge (SOC) constraints create significant challenges. To tackle this, a tailored interval optimization approach is proposed to consider both DSM …

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A New Discontinuous Conduction Mode In A Transformer Coupled High Gain Dc-Dc Converter, Kartikeya J.P. Veeramraju, Jacob Eisen, Joshua L. Rovey, Jonathan W. Kimball Jan 2022

A New Discontinuous Conduction Mode In A Transformer Coupled High Gain Dc-Dc Converter, Kartikeya J.P. Veeramraju, Jacob Eisen, Joshua L. Rovey, Jonathan W. Kimball

Electrical and Computer Engineering Faculty Research & Creative Works

Electrospray space propulsion thrusters often employ transformer coupled high gain dc-dc converters. These thrusters have a unique load resistance profile that can vary dramatically during operation. Transformer coupled high gain dc-dc converters working in very low power modes can enter a unique discontinuous conduction mode (DCM) caused by a coupling effect between the boost and magnetization inductors in the converter. The transformer magnetization current prevents the boost inductors from discharging properly, which causes premature loss of boost action and higher than expected boost inductor voltages. This mechanism generates abnormally high voltages on the converter's output side, leading to converter and …

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Fine-Grained Ship Image Recognition Based On Bcnn With Inception And Am-Softmax, Zhilin Zhang, Ting Zhang, Zhaoying Liu, Peijie Zhang, Shanshan Tu, Yujian Li, Muhammad Waqas Jan 2022

Fine-Grained Ship Image Recognition Based On Bcnn With Inception And Am-Softmax, Zhilin Zhang, Ting Zhang, Zhaoying Liu, Peijie Zhang, Shanshan Tu, Yujian Li, Muhammad Waqas

Research outputs 2022 to 2026

The fine-grained ship image recognition task aims to identify various classes of ships. However, small inter-class, large intra-class differences between ships, and lacking of training samples are the reasons that make the task difficult. Therefore, to enhance the accuracy of the fine-grained ship image recognition, we design a fine-grained ship image recognition network based on bilinear convolutional neural network (BCNN) with Inception and additive margin Softmax (AM-Softmax). This network improves the BCNN in two aspects. Firstly, by introducing Inception branches to the BCNN network, it is helpful to enhance the ability of extracting comprehensive features from ships. Secondly, by adding …

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Physical Layer Authentication Using Ensemble Learning Technique In Wireless Communications, Muhammad Waqas, Shehr Bano, Fatima Hassan, Shanshan Tu, Ghulam Abbas, Ziaul Haq Abbas Jan 2022

Physical Layer Authentication Using Ensemble Learning Technique In Wireless Communications, Muhammad Waqas, Shehr Bano, Fatima Hassan, Shanshan Tu, Ghulam Abbas, Ziaul Haq Abbas

Research outputs 2022 to 2026

Cyber-physical wireless systems have surfaced as an important data communication and networking research area. It is an emerging discipline that allows effective monitoring and efficient real-time communication between the cyber and physical worlds by embedding computer software and integrating communication and networking technologies. Due to their high reliability, sensitivity and connectivity, their security requirements are more comparable to the Internet as they are prone to various security threats such as eavesdropping, spoofing, botnets, man-in-the-middle attack, denial of service (DoS) and distributed denial of service (DDoS) and impersonation. Existing methods use physical layer authentication (PLA), the most promising solution to detect …

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