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Articles 3781 - 3810 of 21795

Full-Text Articles in Engineering

Total Isotropic Sensitivity Measurement In Switched Beam Antenna Systems, Jun Li, Yihong Qi, Wei Yu, Fuhai Li, Jun Fan, Zhiping Yang, Songping Wu, James L. Drewniak Aug 2020

Total Isotropic Sensitivity Measurement In Switched Beam Antenna Systems, Jun Li, Yihong Qi, Wei Yu, Fuhai Li, Jun Fan, Zhiping Yang, Songping Wu, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

Smart antenna systems (SAS) play an important role in wireless communication systems, especially in rapidly developing fifth generation (5G) systems. In normal device under test (DUT) applications with SAS, the antenna's state may change in different external environments in order to obtain higher antenna gains and better connection with the base station, resulting in high uncertainties for over-the-air (OTA) tests using conventional methods. Before evaluating the transceiver performance, additional application programs are necessary to control the DUT, which increases the inconvenience for engineers and makes it impossible to reflect the real usage scenario. This article proposes a new convenient method …

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Physics-Based Circuit Modeling Methodology For System Power Integrity Analysis And Design, Biyao Zhao, Siqi Bai, Samuel Connor, Wiren Dale Becker, Matteo Cocchini, Jonghyun Cho, Albert E. Ruehli, Bruce Archambeault, James L. Drewniak Aug 2020

Physics-Based Circuit Modeling Methodology For System Power Integrity Analysis And Design, Biyao Zhao, Siqi Bai, Samuel Connor, Wiren Dale Becker, Matteo Cocchini, Jonghyun Cho, Albert E. Ruehli, Bruce Archambeault, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

A physics-based circuit modeling methodology for system-level power integrity (PI) analysis and design is presented herein. The modeling methodology is based on representing the current paths in the power distribution network (PDN) with appropriate circuits based on cavity model and plane-pair partial element equivalent circuit (PEEC). The PDN input impedance looking from on-chip sources can be computed. A commercial simulation tool is used to corroborate the modeling approach where the system consists of a commercial integrated circuit, a complex organic package and a very high-layer-count printed circuit board. Two types of circuit models are proposed from the methodology with physical …

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A Mechanism Of Electric Charge Losses In Adiabatically Compressed Ferroelectrics, Sergey I. Shkuratov, Jason Baird, Vladimir G. Antipov, Jay B. Chase Jul 2020

A Mechanism Of Electric Charge Losses In Adiabatically Compressed Ferroelectrics, Sergey I. Shkuratov, Jason Baird, Vladimir G. Antipov, Jay B. Chase

Mining Engineering Faculty Research & Creative Works

A ferroelectric depolarized by high strain-rates induced by the passage of adiabatic shock waves releases a high-density electric charge, initiating the generation of high voltage and megawatt power levels. Additionally, this depolarization process alters physical and mechanical properties that might cause energy and electric charge losses in the ferroelectric materials. We report, herein, the results of an experimental study of electric charge losses in Pb0.99(Zr0.95Ti0.05)0.98Nb0.02O3 and Pb0.99(Zr0.52Ti0.48)0.99Nb0.01O3 ferroelectrics subjected to shock compression. We found that electric charge losses mainly occur in the compressed zone of ferroelectric elements, i.e., shock compression is an essential part of the charge loss mechanism. Based …

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Transceivers As A Resource: Scheduling Time And Bandwidth In Software-Defined Radio, Nathan D. Price, Maciej Jan Zawodniok, Ivan G. Guardiola Jul 2020

Transceivers As A Resource: Scheduling Time And Bandwidth In Software-Defined Radio, Nathan D. Price, Maciej Jan Zawodniok, Ivan G. Guardiola

Electrical and Computer Engineering Faculty Research & Creative Works

In the future, software-defined radio may enable a mobile device to support multiple wireless protocols implemented as software applications. These applications, often referred to as waveform applications, could be added, updated, or removed from a software-radio device to meet changing demands. Current software-defined radio solutions grant an active waveform exclusive ownership of a specific transceiver or analog front-end. Since a wireless device has a limited number of front-ends, this approach puts a hard constraint on the number of concurrent waveform applications a device can support. A growing trend in software-defined radio research is to virtualize front-ends to allow sharing and …

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Investigation Of Honey Thin Film As A Resistive Switching Material For Nonvolatile Memories, Aleksey A. Sivkov, Yuan Xing, Kuan Yew Cheong, Xiangqun Zeng, Feng Zhao Jul 2020

Investigation Of Honey Thin Film As A Resistive Switching Material For Nonvolatile Memories, Aleksey A. Sivkov, Yuan Xing, Kuan Yew Cheong, Xiangqun Zeng, Feng Zhao

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, we report, for the first time, honey thin film as a resistive switching material and its memory behaviors. A dried honey film was sandwiched in between a CuxO bottom electrode and a Cu top electrode to form a metal-insulator-metal structure on a glass substrate. Current-voltage measurements showed that the device exhibited bipolar switching characteristics with Ohmic conduction behavior and a read memory window of 2.6 V. When biased at a read voltage of 0.2 V, the data retention time is over an interval of 104 s and ON/OFF ratio is in the order of 107 …

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Synthesis And Characterization Of Free-Stand Graphene/Silver Nanowire/Graphene Nano Composite As Transparent Conductive Film With Enhanced Stiffness, Chuanrui Guo, Yanxiao Li, Yanping Zhu, Chenglin Wu, Genda Chen Jul 2020

Synthesis And Characterization Of Free-Stand Graphene/Silver Nanowire/Graphene Nano Composite As Transparent Conductive Film With Enhanced Stiffness, Chuanrui Guo, Yanxiao Li, Yanping Zhu, Chenglin Wu, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

As-grown graphene via chemical vapor deposition (CVD) has potential defects, cracks, and disordered grain boundaries induced by the synthesis and transfer process. Graphene/silver nanowire/graphene (Gr/AgNW/Gr) sandwich composite has been proposed to overcome these drawbacks significantly as the AgNW network can provide extra connections on graphene layers to enhance the stiffness and electrical conductivity. However, the existing substrate (polyethylene terephthalate (PET), glass, silicon, and so on) for composite production limits its application and mechanics behavior study. In this work, a vacuum annealing method is proposed and validated to synthesize the free-stand Gr/AgNW/Gr nanocomposite film on transmission electron microscopy (TEM) grids. AgNW …

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Synthesis And Characterization Of Free-Stand Graphene/Silver Nanowire/Graphene Nano Composite As Transparent Conductive Film With Enhanced Stiffness, Chuanrui Guo, Yanxiao Li, Yanping Zhu, Chenglin Wu, Genda Chen Jul 2020

Synthesis And Characterization Of Free-Stand Graphene/Silver Nanowire/Graphene Nano Composite As Transparent Conductive Film With Enhanced Stiffness, Chuanrui Guo, Yanxiao Li, Yanping Zhu, Chenglin Wu, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

As-grown graphene via chemical vapor deposition (CVD) has potential defects, cracks, and disordered grain boundaries induced by the synthesis and transfer process. Graphene/silver nanowire/graphene (Gr/AgNW/Gr) sandwich composite has been proposed to overcome these drawbacks significantly as the AgNW network can provide extra connections on graphene layers to enhance the stiffness and electrical conductivity. However, the existing substrate (polyethylene terephthalate (PET), glass, silicon, and so on) for composite production limits its application and mechanics behavior study. In this work, a vacuum annealing method is proposed and validated to synthesize the free-stand Gr/AgNW/Gr nanocomposite film on transmission electron microscopy (TEM) grids. AgNW …

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Plasmon-Phonon Coupling Between Mid-Infrared Chiral Metasurfaces And Molecular Vibrations, Md Shamim Mahmud, Daniel Rosenmann, David A. Czaplewski, Jie Gao, Xiaodong Yang Jul 2020

Plasmon-Phonon Coupling Between Mid-Infrared Chiral Metasurfaces And Molecular Vibrations, Md Shamim Mahmud, Daniel Rosenmann, David A. Czaplewski, Jie Gao, Xiaodong Yang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Plasmon-phonon coupling between metamaterials and molecular vibrations provides a new path for studying mid-infrared light-matter interactions and molecular detection. So far, the coupling between the plasmonic resonances of metamaterials and the phonon vibrational modes of molecules has been realized under linearly polarized light. Here, mid-infrared chiral plasmonic metasurfaces with high circular dichroism (CD) in absorption over 0.65 in the frequency range of 50 to 60 THz are demonstrated to strongly interact with the phonon vibrational resonance of polymethyl methacrylate (PMMA) molecules at 52 THz, under both left-handed and right-handed circularly polarized (LCP and RCP) light. The mode splitting features in …

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Determination Of Effective Parameters Of Fishnet Metamaterials With Vortex Based Interferometry, Wei Cao, Jie Gao, Xiaodong Yang Jul 2020

Determination Of Effective Parameters Of Fishnet Metamaterials With Vortex Based Interferometry, Wei Cao, Jie Gao, Xiaodong Yang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Metamaterials are artificially engineered structures that have unique properties not usually found in natural materials, such as negative refractive index. Conventional interferometry or ellipsometry is generally used for characterizing the optical properties of metamaterials. Here, we report an alternative optical vortex based interferometric approach for the characterization of the effective parameters of optical metamaterials by directly measuring the transmission and reflection phase shifts from metamaterials according to the rotation of vortex spiral interference pattern. The fishnet metamaterials possessing positive, zero and negative refractive indices are characterized with the vortex based interferometry to precisely determine the complex values of effective permittivity, …

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A Novel Self-Restrained Decoupling Technique For Two Antennas, Min Li, Muhammad Yasir Jamal, Lijun Jiang, Kwan Lawrence Yeung Jul 2020

A Novel Self-Restrained Decoupling Technique For Two Antennas, Min Li, Muhammad Yasir Jamal, Lijun Jiang, Kwan Lawrence Yeung

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a novel self-restrained (SR) decoupling technique (DT) is presented to increase the isolation between two antennas. The 'self-restrained' feature means that the decoupling structure is only attached to the individual antenna itself without demanding any connection to other being coupled ones. The design parameters of the resultant decoupling structure can be precisely derived to achieve high isolations. A two-element monopole array is employed as a benchmark. Results show that good matching and high isolation are achieved simultaneously.

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A Novel Planar Dual Cp Mimo Antenna With Polarization Diversity And High Isolation, Muhammad Yasir Jamal, Min Li, Lijun Jiang Jul 2020

A Novel Planar Dual Cp Mimo Antenna With Polarization Diversity And High Isolation, Muhammad Yasir Jamal, Min Li, Lijun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a low cost planar two-port circularly polarized MIMO patch antenna with the polarization diversity is presented. Three grounded stubs and a mirrored F defected ground slot are used to achieve simultaneous matching and isolation between the two patch and offset feeding for circular polarization. The proposed antenna covering 2.5-2.55 GHz is fabricated and measured. Its measured performance show that \mathbf{\mathrm{S}_{11} < -10\ \mathrm{dB},\ \mathrm{S}_{12} < -20\ \mathrm{dB}} and axial ratio \mathbf{< 3\mathrm{dB}} for the whole band. Its radiation patterns and gain are also measured and an agreement with the simulation result has been achieved.

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A Novel Wideband Decoupling Network For Two Antennas, Min Li, Muhammad Yasir Jamal, Lijun Jiang, Kwan Lawrence Yeung Jul 2020

A Novel Wideband Decoupling Network For Two Antennas, Min Li, Muhammad Yasir Jamal, Lijun Jiang, Kwan Lawrence Yeung

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a novel wideband decoupling network (DN) is presented, which consists of two 2-way Wilkinson power dividers (WPDs), three transmission lines, and two reactive components. Rigorous design formulas are presented along with systematic design procedures. The transmission-line lengths and component reactances are precisely calculated to achieve high antenna isolation. Measurement results show that a very wide isolation bandwidth of 23.7% can be achieved after using the proposed DN.

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A Spatially Distributed Fiber-Optic Temperature Sensor For Applications In The Steel Industry, Muhammad Roman, Damilola Balogun, Yiyang Zuang, Rex E. Gerald Ii, Laura Bartlett, Ronald J. O'Malley, Jie Huang Jul 2020

A Spatially Distributed Fiber-Optic Temperature Sensor For Applications In The Steel Industry, Muhammad Roman, Damilola Balogun, Yiyang Zuang, Rex E. Gerald Ii, Laura Bartlett, Ronald J. O'Malley, Jie Huang

Materials Science and Engineering Faculty Research & Creative Works

This paper presents a spatially distributed fiber-optic sensor system designed for demanding applications, like temperature measurements in the steel industry. The sensor system employed optical frequency domain reflectometry (OFDR) to interrogate Rayleigh backscattering signals in single-mode optical fibers. Temperature measurements employing the OFDR system were compared with conventional thermocouple measurements, accentuating the spatially distributed sensing capability of the fiber-optic system. Experiments were designed and conducted to test the spatial thermal mapping capability of the fiber-optic temperature measurement system. Experimental simulations provided evidence that the optical fiber system could resolve closely spaced temperature features, due to the high spatial resolution and …

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A Data-Driven Approach For Winter Precipitation Classification Using Weather Radar And Nwp Data, Bong Chul Seo Jul 2020

A Data-Driven Approach For Winter Precipitation Classification Using Weather Radar And Nwp Data, Bong Chul Seo

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study describes a framework that provides qualitative weather information on winter precipitation types using a data-driven approach. The framework incorporates the data retrieved from weather radars and the numerical weather prediction (NWP) model to account for relevant precipitation microphysics. To enable multimodel-based ensemble classification, we selected six supervised machine learning models: k-nearest neighbors, logistic regression, support vector machine, decision tree, random forest, and multi-layer perceptron. Our model training and cross-validation results based on Monte Carlo Simulation (MCS) showed that all the models performed better than our baseline method, which applies two thresholds (surface temperature and atmospheric layer thickness) for …

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Investigation And Mitigation Of Radio Frequency Interference Caused By Weak Grounding Of Usb Type-C Receptacle Connector, Anfeng Huang, Xin Yan, Jingdong Sun, Qiaolei Huang, Jun Fan, Songping Wu, Dave Zhang, Huan Liao, Shuai Jin, Zhiping Yang Jul 2020

Investigation And Mitigation Of Radio Frequency Interference Caused By Weak Grounding Of Usb Type-C Receptacle Connector, Anfeng Huang, Xin Yan, Jingdong Sun, Qiaolei Huang, Jun Fan, Songping Wu, Dave Zhang, Huan Liao, Shuai Jin, Zhiping Yang

Electrical and Computer Engineering Faculty Research & Creative Works

In modern mobile electronic systems, USB connector has been identified as one of the dominant noise sources for desense issues. In this paper, the noise coupled to the Wi-Fi antenna from a USB connector is investigated. With the assistance of full-wave simulations, the root cause of desense noise is identified as the non-ideal electrical connection between the metal chassis and the USB receptacle shell where it is installed. The proposed radiation mechanism is validated through measurements of a real tablet device, and 15 dB noise level reduction is observed with a better grounding structure.

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Random Packing Material In Disinfection Contactors: Effects On Final Drinking Water Quality, Jessica L. Baker, Susan K. De Long, Subhas K. Venayagamoorthy Jul 2020

Random Packing Material In Disinfection Contactors: Effects On Final Drinking Water Quality, Jessica L. Baker, Susan K. De Long, Subhas K. Venayagamoorthy

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study investigates the concern about biofilm growth on random packing material (RPM) used to enhance the hydraulic disinfection efficiency of a chlorine contactor. The inflow, outflow, and RPM were monitored for heterotrophic bacteria (via heterotrophic plate counts) and Pseudomonas aeruginosa as indicators of bacteriological water quality and the presence of biofilm. The results of this study show that there was no substantial biofilm growth in a lab-scale chlorine contactor and no substantial increase in bacterial counts for the bulk outflow over a 10-week period. Thus, the potential for excessive biofilm growth should not be considered a barrier concerning the …

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Deep Learning Based Poisson Solver In Particle Simulation Of Pn Junction With Transient Esd Excitation, Ling Zhang, Wenchang Huang, Zeyi Sun, Nicholas Erickson, Ryan From, Jun Fan Jul 2020

Deep Learning Based Poisson Solver In Particle Simulation Of Pn Junction With Transient Esd Excitation, Ling Zhang, Wenchang Huang, Zeyi Sun, Nicholas Erickson, Ryan From, Jun Fan

Engineering Management and Systems Engineering Faculty Research & Creative Works

In particle simulations of semiconductor devices for electro-static discharge (ESD) study at the microscopic level, solving Poisson's equation is an inevitable but time-consuming step. In this work, a deep learning technique is utilized to resolve Poisson's equation for a PN junction under an ESD event, namely using a trained deep neural network (DNN) to predict the potential distribution according to the charge distribution and the boundary condition under a transient ESD excitation. To improve the generalization performance of the DNN, multiple typical ESD curves with different parameters are used as the excitation boundary to generate large amounts of training data …

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Adaptive Interference Mitigation Using Frequency-Selective Limiters Over Gps Band For Automotive Applications, Mahima Shukla, Marina Y. Koledintseva, Michael Geiler, Scott Gillette, Michael Hunnewell, Anton L. Geiler Jul 2020

Adaptive Interference Mitigation Using Frequency-Selective Limiters Over Gps Band For Automotive Applications, Mahima Shukla, Marina Y. Koledintseva, Michael Geiler, Scott Gillette, Michael Hunnewell, Anton L. Geiler

Electrical and Computer Engineering Faculty Research & Creative Works

In this work, we address the challenges associated with the necessity to protect Global Positioning system (GPS) receivers from various types of electromagnetic interference (EMI) generated by internal or external sources. We have developed a compact, lightweight, and passive frequency selective limiter (FSL) technology that automatically and adaptively protects vulnerable input circuits of a GPS receiver from unwanted emissions and prevents a GPS receiver from going into saturation. This technology is based on using magnetostatic surface waves in a magnetically biased ferrite film. The nonlinear processes in ferrite films enable discrimination of signals based on their power levels. In these …

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Predicting The Conducted Emission Of A Crm Pfc Below 1mhz By Transient Modeling, Hongseok Kim, Jiayi He, Chunyu Wu, Nicholas Erickson, Sangho Cho, Dohyung Kim, Yeong Hur, Jun Fan Jul 2020

Predicting The Conducted Emission Of A Crm Pfc Below 1mhz By Transient Modeling, Hongseok Kim, Jiayi He, Chunyu Wu, Nicholas Erickson, Sangho Cho, Dohyung Kim, Yeong Hur, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

Power Factor Corrections (PFC) are widely used in ac to dc power supplies. Modeling the PFC circuits and predicting the conducted emission (CE) are important in power supply designs. This paper introduces a transient model of a critical conduction mode (CRM) power factor correction. The control circuit of the PFC is built to achieve a CRM working condition with a constant on-time switching. The simulated time domain noise waveform is converted to the conducted EMI in frequency domain via short-time fast Fourier transform (STFFT). The simulated conducted EMI is compared to measured results below 1MHz.

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Effects Of Zirconia Doping On Additively Manufactured Alumina Ceramics By Laser Direct Deposition, John M. Pappas, Aditya R. Thakur, Xiangyang Dong Jul 2020

Effects Of Zirconia Doping On Additively Manufactured Alumina Ceramics By Laser Direct Deposition, John M. Pappas, Aditya R. Thakur, Xiangyang Dong

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The ability to additively manufacture functional alumina ceramics has the potential to lower manufacturing costs and development time for complex components. In this study, the doping effects of zirconia on laser direct deposited alumina ceramics were investigated. The microstructure of the printed samples was analyzed in terms of grain size and composition distribution. The addition of zirconia was found to accumulate along alumina grain boundaries and resulted in significant grain refinement. The zirconia doping largely reduced crack formation during processing compared to that of pure alumina samples. In the case of 10 wt% zirconia, cracking during deposition was nearly completely …

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Improved Classification Of Medical Data Using Meta-Best Feature Selection, Matthew Chaplin, Jacob Grubb, Thomas Clifford, Justin Bruce, Tayo Obafemi-Ajayi, John Matta Jul 2020

Improved Classification Of Medical Data Using Meta-Best Feature Selection, Matthew Chaplin, Jacob Grubb, Thomas Clifford, Justin Bruce, Tayo Obafemi-Ajayi, John Matta

Electrical and Computer Engineering Faculty Research & Creative Works

Feature selection provides a useful method for reducing the size of large data sets while maintaining integrity, thereby improving the accuracy of neural networks and other classifiers. However, running multiple feature selection models and their accompanying classifiers can make interpreting results difficult. To this end, we present a data-driven methodology called Meta-Best that not only returns a single feature set related to a classification target, but also returns an optimal size and ranks the features by importance within the set. This proposed methodology is tested on six distinct targets from the well-known REGARDS dataset: Deceased, Self-Reported Diabetes, Light Alcohol Abuse …

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A Design Of Taper-Like Etched Multicore Fiber Refractive Index-Insensitive A Temperature Highly Sensitive Mach-Zehnder Interferometer, Farhan Mumtaz, Pu Cheng, Chi Li, Shu Cheng, Cheng Du, Minghong Yang, Yutang Dai, Wenbin Hu Jul 2020

A Design Of Taper-Like Etched Multicore Fiber Refractive Index-Insensitive A Temperature Highly Sensitive Mach-Zehnder Interferometer, Farhan Mumtaz, Pu Cheng, Chi Li, Shu Cheng, Cheng Du, Minghong Yang, Yutang Dai, Wenbin Hu

Electrical and Computer Engineering Faculty Research & Creative Works

We propose and demonstrate Mach-Zehnder interferometer (MZI), which is the refractive index (RI) insensitive and temperature highly sensitive based on etched multi-core fiber (MCF) structure. The MCF and Fiber Bragg Grating (FBG) are used as hybrid sensing elements. The fabrication of the interferometer is provided a new taper-like structure by etching the MCF to further expose the side cores to the surroundings. The interferometer has produced a sensitivity of 103.2pm/°C within the ambient temperature up-to 70°C. Moreover, the superior temperature sensitivity is 89.19pm/°C, 66.64pm/°C, 56.42pm/°C in the range of 24°C to 130°C, and RI-insensitive in the range of 1.34 to …

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An Algorithm For The Evolutionary-Fuzzy Generation Of On-Line Signature Hybrid Descriptors, Marcin Zalasinski, Krzysztof Cpalka, Lukasz Laskowski, Donald C. Wunsch, Krzystof Przybyszewski Jul 2020

An Algorithm For The Evolutionary-Fuzzy Generation Of On-Line Signature Hybrid Descriptors, Marcin Zalasinski, Krzysztof Cpalka, Lukasz Laskowski, Donald C. Wunsch, Krzystof Przybyszewski

Electrical and Computer Engineering Faculty Research & Creative Works

In biometrics, methods which are able to precisely adapt to the biometric features of users are much sought after. They use various methods of artificial intelligence, in particular methods from the group of soft computing. In this paper, we focus on on-line signature verification. Such signatures are complex objects described not only by the shape but also by the dynamics of the signing process. In standard devices used for signature acquisition (with an LCD touch screen) this dynamics may include pen velocity, but sometimes other types of signals are also available, e.g. pen pressure on the screen surface (e.g. in …

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Optimal Control Of Linear Continuous-Time Systems In The Presence Of State And Input Delays With Application To A Chemical Reactor, Rohollah Moghadam, Sarangapani Jagannathan Jul 2020

Optimal Control Of Linear Continuous-Time Systems In The Presence Of State And Input Delays With Application To A Chemical Reactor, Rohollah Moghadam, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, the optimal regulation of linear continuous-time systems with state and input delays is introduced by utilizing a quadratic cost function and state feedback. The Lyapunov-Krakovskii functional incorporating state and input delays is defined as a value function. Next, the Bellman type equation is formulated, and a delay Algebraic Riccati equation (DARE) over infinite time horizon is derived. By using the stationarity condition for the Bellman type equation, the optimal control input is obtained. It is demonstrated that the proposed optimal control input makes the closed-loop system asymptotically stable. Finally, simulation results confirm the theoretical claims by applying …

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Complex Permittivity Extraction From Synthetic Aperture Radar Images, Yuan Gao, Mohammad Tayeb Al Qaseer, Reza Zoughi Jul 2020

Complex Permittivity Extraction From Synthetic Aperture Radar Images, Yuan Gao, Mohammad Tayeb Al Qaseer, Reza Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Microwave and millimeter wave synthetic aperture radar (SAR) imaging techniques are commonly used to generate high-resolution qualitative images showing the reflectivity (or complex permittivity) contrast in a sample-under-test (SUT). These techniques have been successfully applied for many diverse applications. However, these images lack quantitative information about the SUT, namely, its complex permittivity distribution. In this article, a novel method to extract the spatial distribution of complex permittivity from SAR images is proposed. The principle of the proposed method is outlined, then verified by a series of electromagnetic simulations, demonstrating that the proposed method can accurately extract the complex permittivity. Additionally, …

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Distributed Adaptive State Estimation And Tracking Scheme For Nonlinear Systems Using Active Passive Sensor Networks, Akhilesh Raj, S. Jagannathan, Tansel Yucelen Jul 2020

Distributed Adaptive State Estimation And Tracking Scheme For Nonlinear Systems Using Active Passive Sensor Networks, Akhilesh Raj, S. Jagannathan, Tansel Yucelen

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a novel adaptive neural network (NN) based distributed state estimation scheme for a heterogeneous sensor network (HSN), to estimate the state vector of an unknown nonlinear process/target by using sensed output when the target input remains unknown. The active nodes in the HSN can sense the target output based on the detection range. By using a connected graph, the active nodes will communicate their estimated state vector from their adaptive NN observer to other passive nodes in the neighborhood that cannot sense the target, so that they can estimate the target state vector. Next, a subset of …

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Dynamic Trajectory Generation And A Robust Controller To Intercept A Moving Ball In A Game Setting, Ravi Prakash, Laxmidhar Behera, Santhakumar Mohan, Sarangapani Jagannathan Jul 2020

Dynamic Trajectory Generation And A Robust Controller To Intercept A Moving Ball In A Game Setting, Ravi Prakash, Laxmidhar Behera, Santhakumar Mohan, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

Complex and interactive robot manipulation skills, such as playing a game of table tennis against a human opponent, are a novel problem with multifaceted challenges. Accurate dynamic trajectory generation in order to respond to the tennis ball from the opponent and a novel control scheme for robust and high-performance tracking of the ball in such dynamic situations is a prerequisite to winning the game. In this paper, the dynamic movement primitives (DMPs) are employed for the stable generation of dynamic trajectories in the presence of environmental uncertainties such as ball position and velocity, opponent position and velocity and so on. …

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Noise Coupling Mechanism Analysis And Mitigation Method For Receiver Sensitivity Improvement In An Optical Qsfp Transceiver Module, Yuandong Guo, Shuai Jin, Xinglin Sun, Jun Fan Jul 2020

Noise Coupling Mechanism Analysis And Mitigation Method For Receiver Sensitivity Improvement In An Optical Qsfp Transceiver Module, Yuandong Guo, Shuai Jin, Xinglin Sun, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

The increasingly growth of the traffic in data centers demands for high-speed data transition and high bandwidth density. Optical communication is a promising way for the propagation of high-speed signals with less distortions. The quad small form-factor pluggable (QSFP) transceiver module is an essential component converting an electrical signal into an optical signal for point-to-point data transition. Considerable attentions have been paid to the signal integrity (SI) optimization for the optical QSFP transceiver modules with different data rates, where the receiver sensitivity is generally considered to be critical. In this paper, the receiver sensitivity problem of a typical QSFP transceiver …

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Effect Of Rf Signals On Tvs Diode Trigger Voltage For Esd Protection, Giorgi Maghlakelidze, Shubhankar Marathe, Wei Huang, Joost Willemen, David Pommerenke Jul 2020

Effect Of Rf Signals On Tvs Diode Trigger Voltage For Esd Protection, Giorgi Maghlakelidze, Shubhankar Marathe, Wei Huang, Joost Willemen, David Pommerenke

Electrical and Computer Engineering Faculty Research & Creative Works

Discrete transient voltage suppressor devices are used in addition to the on-chip ESD protection to protect the ICs from ESD damage. In applications involving snapback TVS devices, the trigger voltage is selected to be higher than the desired signals on the net. The presence of RF on the net affects the TVS behavior, even if the RF levels are less than the snapback trigger voltage. Known effects are RF intermodulation and harmonic generation, which diminish SNR. This work describes the other effect on the TVS diodes - the observed reduction of the snapback trigger voltage, monotonically dependent on the amplitude …

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Generic Modeling Of Differential Striplines Using Machine Learning Based Regression Analysis, Srinath Penugonda, Shaohui Yong, Anna Gao, Kevin Cai, Bidyut Sen, Jun Fan Jul 2020

Generic Modeling Of Differential Striplines Using Machine Learning Based Regression Analysis, Srinath Penugonda, Shaohui Yong, Anna Gao, Kevin Cai, Bidyut Sen, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a generic model for a differential strip line is created using machine learning (ML) based regression analysis. A recursive approach of creating various inputs is adapted instead of traditional design of experiments (DoE) approach. This leads to reduction of number of simulations as well as control the data points required for performing simulations. The generic model is developed using 48 simulations. It is comparable to the linear regression model, which is obtained using 1152 simulations. Additionally, a tabular W-element model of a differential strip line is used to take into consideration the frequency-dependent dielectric loss. In order …

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