Electrical and Computer Engineering Commons^™

Cmi Analysis And Precoding Designs For Correlated Multi-Hop Mimo Channels, Nguyen N. Tran, Song Ci, Ha X. Nguyen

Department of Electrical and Computer Engineering: Faculty Publications

Conditional mutual information (CMI) analysis and precoding design for generally correlated wireless multi-hop multi-input multi-output (MIMO) channels are presented in this paper. Although some particular scenarios have been examined in existing publications, this paper investigates a generally correlated transmission system having spatially correlated channel, mutually correlated source symbols, and additive colored Gaussian noise (ACGN). First, without precoding techniques, we derive the optimized source symbol covariances upon mutual information maximization. Secondly, we apply a precoding technique and then design the precoder in two cases: maximizing the mutual information and minimizing the detection error. Since the optimal design for the end-to-end system …

Integral Equation Analysis Of Em Scattering From Multilayered Metallic Photonic Crystal Accelerated With Adaptive Cross Approximation, Jianxun Su, Zengrui Li, Xujin Yuan, Yaoqing (Lamar) Yang, Junhong Wang

Department of Electrical and Computer Engineering: Faculty Publications

A space-domain integral equation method accelerated with adaptive cross approximation (ACA) is presented for the fast and accurate analysis of electromagnetic (EM) scattering from multilayered metallic photonic crystal (MPC). The method directly solves for the electric field in order to easily enable the periodic boundary condition (PBC) in the spatial domain. The ACA is a purely algebraic method allowing the compression of fully populated matrices; hence, its formulation and implementation are independent of integral equation kernel (Green’s function).Therefore, the ACA is very well suited for accelerating integral equation analysis of periodic structure with the integral kernel of the periodic Green’s …

Drive Systems Including Sliding Mode Observers And Methods Of Controlling The Same, Long Wu, Yue Zhao, Wei Qiao

Department of Electrical and Computer Engineering: Faculty Publications

At least one example embodiment discloses a drive system including a motor including a rotor, the motor configured to receive a measured current, a controller configured to generate a Voltage command for the motor, a sliding mode observer configured to determine an estimated current for the motor based on the Voltage command, determine a difference between the measured current and the estimated current, and determine a Switching control vector and an estimator con figured to estimate a rotor position based on the Switching control vector, the Switching control vector being determined based on the difference and adaptive parameters of the …

Probes For Multidimensional Nanospectroscopic Imaging And Methods Of Fabrication Thereof, Alexander Weber-Bargionii, Stefano Cabrini, Wei Bao, Mauro Melli, Eli Yablonovitch, Peter J. Schuck

Department of Electrical and Computer Engineering: Faculty Publications

This disclosure provides systems, methods, and apparatus related to probes for multidimenisonal nanospectroscopic imaging. In one aspect, a method includes providing a transparent tip comprising a dielectric material. A four-sided pyramidal-shaped structure is formed at an apex of the transparent tip using a focus ion beam. Metal layers are deposited over two opposing sides of the four-sided pyramidal-shaped structure.

A Study Of The Impact Of Various Geometric Factors On The Capacity Of Short Range Indoor Mimo Communications Channels, Anthony Grennan

Doctoral

MIMO antenna array systems have been proposed as a means of increasing the spectral efficiency of wireless systems. However, their performance is likely to be sub-optimal if typical uniform antenna array structures are arbitrarily positioned; as they depend on spatial multiplexing. This is particularly true for indoor environments in which transmission ranges are short resulting in a strong correlation of the main propagation paths, especially the line-of-sight components. This makes it difficult to achieve successful spatial multiplexing which depends on a decorrelated set of signal components. Thus, the physical propagation channel and geometry of the antenna arrays, especially the inter-element …

Study Of Uhf And Vhf Compact Antennas, Abraham Loutridis

Doctoral

This thesis presents and describes designs of small antennas that operate in UHF and VHF frequency bands. The proposed antennas are designed for integration into small volumes, therefore low profile, compact size and good radiation properties are the key parameters in this work. A further investigation on miniaturization techniques, as well as the ground plane effects on the general performance, is also made. The main objective is the design of novel compact sized geometries, lightweight and cost efficient, operating in the lower UHF and VHF frequency bands. The groundplane size and the antenna position with respect to it, are two …

On A New Method For Interior Lighting Design, James Duff

Doctoral

In 2009, Christopher Cuttle began to challenge the suitability of the metrics contained within current lighting design standards and guidance. In short, Cuttle proposed a move away from providing an amount of light that relates to the difficulty of a visual task and instead, providing an amount of light that relates to the brightness of a space. This sense of brightness would be estimated by a new lighting metric, Mean Room Surface Exitance. The research presented in this thesis strove to examine, critically evaluate, analyse and investigate the merit of changing indoor lighting standards to include Mean Room Surface Exitance. …

Broadband Coherent Perfect Absorption In One-Dimensional Optical Systems, Massimo Maximilian Villinger

Electronic Theses and Dissertations

Absorption plays a critical role in a variety of optical applications – sometimes it is desirable to minimize it as in optical fibers and waveguides, or to enhance it as in solar cells and photodetectors. We describe here a new optical scheme that controllably produces high optical absorption over a broad wavelength range (hundreds of nm) in systems that have low intrinsic absorption over the same range. This effect, 'coherent perfect absorption' or CPA, arises from a subtle interplay between interference and absorption of two beams incident on a weakly absorbing medium. In the first part of this study, we …

Assessment Of Electrode Configurations Of Electrical Impedance Myography For The Evaluation Of Neuromuscular Diseases, Khondokar Mohammad Fazle Rabbi

College of Graduate Studies: Theses & Dissertations

Electrical impedance myography (EIM) is a painless, noninvasive approach to measure the neuromuscular disease status. EIM parameters- resistance (R), reactance (X) and phase (θ) depend significantly on subcutaneous fat thickness, muscle size and inter electrode distance. The objective of this research is to find an electrode configuration which can minimize the effects on EIM parameters due to subcutaneous fat thickness variation. In this study, a model of human upper arm was developed using finite element method (FEM), which has already been established as an appropriate approach for the analysis of non-symmetrical shape for assessing alternations of muscle in disease-induced changes …

Breaking The Buildup-Time Limit Of Sensitivity In Avalanche Photodiodes By Dynamic Biasing, Majeed M. Hayat, Payman Zarkesh-Ha, George El-Howayek, Robert Efroymson, Joe C. Campbell

Electrical and Computer Engineering Faculty Research and Publications

Avalanche photodiodes (APDs) are the preferred photodetectors for direct-detection, high data-rate long-haul optical telecommunications. APDs can detect low-level optical signals due to their internal amplification of the photon-generated electrical current, which is attributable to the avalanche of electron and hole impact ionizations. Despite recent advances in APDs aimed at reducing the average avalanche-buildup time, which causes intersymbol interference and compromises receiver sensitivity at high data rates, operable speeds of commercially available APDs have been limited to 10Gbps. We report the first demonstration of a dynamically biased APD that breaks the traditional sensitivity-versus-speed limit by employing a data-synchronous sinusoidal reverse-bias that …

Integrating Emerging Cryptographic Engineering Research And Security Education, Mehran Mozaffari Kermani, Reza Azarderakhsh

Articles

Unlike traditional embedded systems such as secure smart cards, emerging secure deeply embedded systems, e.g., implantable and wearable medical devices, have larger “attack surface”. A security breach in such systems which are embedded deeply in human bodies or objects would be life-threatening, for which adopting traditional solutions might not be practical due to tight constraints of these often-battery-powered systems. Unfortunately, although emerging cryptographic engineering research mechanisms have started solving this critical problem, university education (at both graduate and undergraduate level) lags comparably. One of the pivotal reasons for such a lag is the multi-disciplinary nature of the emerging security bottlenecks …

Strain Controlled Ultra-Low-Energy Magnetic Tunneling Junction, Hasnain Ahmad, Supriyo Bandyopadhyay, Jayasimha Atulasimha

Graduate Research Posters

We are experimenting on designing a voltage-controlled ultra-low-energy Magnetic Tunneling Junction (MTJ) device using a soft single domain magnetostrictive layer (i.e. Galfenol: Fe_1-xGa_x , x = 20 At%) coupled to a piezoelectric layer (i.e. PMN-PT). Special metal pads have been designed using photolithography to generate stress in the PMN-PT layer by applying electric field. The patterns of different shape anisotropic nano-magnets are designed using e-beam lithography and we have successfully fabricate FeGa nanomagnets with only 12 to 13 nanometer thickness by sputter deposition. These nanomagnets have been characterized by magnetic force microscopy for observing their switching capabilities. …

Coherent Spin Transport In Nanowire Spin Valves And Novel Spintronic Device Possibilities, Md Iftekhar I. Hossain, Supriyo Bandyopadhyay, Jayasimha Atulasimha, Saumil Bandyopadhyay

Graduate Research Posters

We have proposed a spintronic infrared photodetector backed by experimental evidence and matched with theoretical prediction obtained in our labs. Unlike conventional photodetectors, it can work at room temperature with ideally infinite light-to-dark contrast ratio, infinite detectivity and zero dark current. The proposed idea is based on smart implementation of spin polarized transport. Electrons while travelling through one-dimensional channel show long spin relaxation length if they can be confined to a single conduction subband because of the elimination of major spin relaxation mechanism, namely the D’yakonov-Perel’ mechanism. With infrared light, electrons can be excited to higher subbands, resulting in the …

Large Dynamic Range Amplifier Plus Adc, Ted Hsueh

Electrical Engineering

Nerve and muscle signal sampling proves difficult because of the large difference in magnitudes. Muscle signals loom a hundred or even a thousand times bigger and can hide the nerve signals. The Large Dynamic Range Amplifier plus Analog to Digital Converter (ADC) allows one device to retrieve both muscle and nerve signal information. The device has two parts: the ability to take high-resolution data from tenths of microvolts to several millivolts and filter out environmental noise, such as 60 Hz of electrical power lines or electro galvanic signals. This gives the ability to read muscle and nerve signals using one …

Boost Battery, Samuel Rauch, Alvin Ng, Lacy Sigman

Electrical Engineering

In modern times, the problem of a depleted battery confronts us too often. Whether it appears with a smartphone or with any other electronic device, the situation frustrates all consumers. This project designs and constructs a compact portable battery charger that charges through kinetic energy. Thus, one can perform everyday activities, such as walking or running, and charge up a backup battery with no extra effort or time. Additionally, an attachable band harvests thermal energy to maximize the amount of clean power generated. Energy harvesting from kinetic motion and thermal differences provide users with power when no actual power suppliers …

Steady-State Analysis Of Pwm Z-Bridge Source Dc-Dc Converter, Lokesh Kathi

Browse all Theses and Dissertations

A PWM Z-bridge source dc-dc converter has a potential to play a prominent role in renewable energy applications, as it provides boosted and regulated output voltage and also behaves as an intermediate buffer between the source and the load. A complete circuit analysis of the Z-bridge source converter is needed to understand the operation of this converter. Steady-state analysis of pulse-width modulated (PWM) Z-bridge source dc-dc converter operating in continuous conduction mode (CCM) is given. Expressions describing waveforms of voltages across and currents through the all components of the PWM Z-bridge source dc-dc converter to operate in steady-state condition are …

Automatic Pmg Controller For Small Applications, William Scott Adkins

Browse all Theses and Dissertations

This thesis is used to describe the proof of concept and design for a much needed answer to a major flight time limitation in smaller application drones. All small electric drones and small electric vehicles have the same major problem, short run-times. The average time a multi-rotor helicopter runs is for approximately 20 minutes. The concept idea of the combination of a permanent magnet generator (PMG) and a controller can extend this flight time. The basic idea is to add the similar function an automobile has, which is the alternator. This thesis will include, but not limited to the following …

Average Current-Mode Control, Ankit Chadha

Browse all Theses and Dissertations

In this thesis, an average current-mode controller is analyzed for controlling power electronic converters. This controller consists of two loops. An inner loop, which senses and controls the inductor current and an outer loop, which is used to control the output voltage and provide reference voltage for the inner current loop. An average current-mode controller averages out high frequency harmonics it senses from the inductor current to provide a smooth DC component. This can be used as a control voltage for a pulse width modulator and produce switching pulses for the power electronic converters. An average current-mode controller can also …

Development Of An Android Based Game Interfaced With Qr Codes For A Gamified Power Management System, Mariano Jesus M. Cayabyab, Maria Rosa T. Santiago, Samuel Matthew G. Dumlao, Rosula Sj Reyes

Electronics, Computer, and Communications Engineering Faculty Publications

- Filipinos are under the threat of an energy shortage. While efforts are being done both in the public and private sectors in developing alternative solutions to ease the shortage, it will take several years before this will come to full implementation. Conservation of energy through power management is the simplest and closest to implement at this time. Filipino households need to be motivated to use smart energy conservation. The introduction of Gamification as a method of motivations has found its use in many applications. In this study the possibility of Gamification to encourage the use of smart energy conservation …

3d-Printed Hand Controlled By Arm Gestures To Verify The Robustness And Reliability Of A Low Cost Surface Electromyography System, Ma. Erika Manlapaz, Marie Perrot, Gabrielle Villavicencio, Bryan Lao, Rosula Sj Reyes

Electronics, Computer, and Communications Engineering Faculty Publications

The study focuses on the development of a low-cost surface electromyography and 3D-printed hand gesture-recognition system. The complete system captures four (4) channels of EMG data through sEMG amplifier circuits interfaced to an Arduino prototyping board. This data is sent to a workstation wherein the graphical user interface shows the pre-processed signal. The gestures are used as control for the movements of the 3D-printed arm.

Interactive Markov Models Of Evolutionary Algorithms, Haiping Ma, Daniel J. Simon, Minrui Fei, Hongwei Mo

Electrical and Computer Engineering Faculty Publications

This paper introduces a Markov model for evolutionary algorithms (EAs) that is based on interactions among individuals in the population. This interactive Markov model has the potential to provide tractable models for optimization problems of realistic size. We propose two simple discrete optimization search strategies with population-proportion-based selection and a modified mutation operator. The probability of selection is linearly proportional to the number of individuals at each point of the search space. The mutation operator randomly modifies an entire individual rather than a single decision variable. We exactly model these optimization search strategies with interactive Markov models. We present simulation …

Proactive Conversation, 3d Printing, And An Old Nintendo, Tesha C. Ellis

Undergraduate Research Posters

Abstract

One hundred years from now, it would be a true historical treat to be able to showcase 20th and 21st century digital entertainment by presenting video game consoles in mint condition for interactive, educational, play. Arguably, it would be more enlightening and informative for future audiences to be able to physically engage with the electronic artifacts instead of simply observing them behind glass. With the use of 3D technology, components of video game systems can be preserved, and then printed as needed for repairs. It will help keep them functional for future researchers, educators, and enthusiasts.

High Efficiency And Wide Color Gamut Liquid Crystal Displays, Zhenyue Luo

Electronic Theses and Dissertations

Liquid crystal display (LCD) has become ubiquitous and indispensable in our daily life. Recently, it faces strong competition from organic light emitting diode (OLED). In order to maintain a strong leader position, LCD camp has an urgent need to enrich the color performance and reduce the power consumption. This dissertation focuses on solving these two emerging and important challenges. In the first part of the dissertation we investigate the quantum dot (QD) technology to improve the both the color gamut and the light efficiency of LCD. QD emits saturated color and grants LCD the capability to reproduce color vivid images. …

Entanglement And Coherence In Classical And Quantum Optics, Kumel Kagalwala

Electronic Theses and Dissertations

We explore the concepts of coherence and entanglement as they apply to both the classical and quantum natures of light. In the classical domain, we take inspiration from the tools and concepts developed in foundational quantum mechanics and quantum information science to gain a better understanding of classical coherence theory of light with multiple degrees of freedom (DoFs). First, we use polarization and spatial parity DoFs to demonstrate the notion of classical entanglement, and show that Bell's measure can serve as a useful tool in distinguishing between classical optical coherence theory. Second, we establish a methodical yet versatile approach called …

Atmospheric Pressure Chemical Vapor Deposition Of Functional Oxide Materials For Crystalline Silicon Solar Cells, Kristopher Davis

Electronic Theses and Dissertations

Functional oxides are versatile materials that can simultaneously enable efficiency gains and cost reductions in crystalline silicon (c-Si) solar cells. In this work, the deposition of functional oxide materials using atmospheric pressure chemical vapor deposition (APCVD) and the integration of these materials into c-Si solar cells are explored. Specifically, thin oxide films and multi-layer film stacks are utilized for the following purposes: (1) to minimize front surface reflectance without increasing parasitic absorption within the anti-reflection coating(s); (2) to maximize internal back reflectance of rear passivated cells, thereby increasing optical absorption of weakly absorbed long wavelength photons (? > 900 nm); (3) …

White Light Continuum For Broadband Nonlinear Spectroscopy, Trenton Ensley

Electronic Theses and Dissertations

Supercontinuum (SC) generation, oftentimes referred to as white-light continuum (WLC), has been a subject of interest for more than 40 years. From the first observation of WLC in condensed media in the early 1970s to the first observation of WLC in gases in the mid-1980s, much work has been devoted to developing a framework for understanding the complex nature of this phenomenon as well as discovering its utility in various applications. The main effort of this dissertation is to develop a WLC for the purpose of broadband nonlinear spectroscopy and use it in spectroscopic measurements. The ability to generate a …

Using Robots As Therapeutic Agents To Teach Children With Autism Recognize Facial Expression, Seyedmohammad Mavadati, Huanghao Feng, Peyten B. Sanger, S. Silver, Anibal Gutierrez, Mohammad H. Mahoor

Electrical and Computer Engineering: Graduate Student Scholarship

Background: Recognizing and mimicking facial expressions are important cues for building great rapport and relationship in human-human communication. Individuals with Autism Spectrum Disorder (ASD) have often deficits in recognizing and mimicking social cues, such as facial expressions. In the last decade several studies have shown that individuals with ASD have superior engagement toward objects and particularly robots (i.e. humanoid and non-humanoid). However, majority of the studies have focused on investigating robot’s appearances and the engineering design concepts and very few research have been done on the effectiveness of robots in therapeutic and treatment applications. In fact, the critical question that …

Two-Photon Absorption In Bulk Semiconductors And Quantum Well Structures And Its Applications, Himansu Pattanaik

Electronic Theses and Dissertations

The purpose of this dissertation is to provide a study and possible applications of two-photon absorption (2PA), in direct-gap semiconductors and quantum-well (QW) semiconductor structures. One application uses extremely nondegenerate (END) 2PA, for mid-infrared (mid-IR) detection in uncooled semiconductors. The use of END, where the two photons have very different energies gives strong enhancement comapared to degenerate 2PA. This END-2PA enhanced detection is also applied to mid-IR imaging and light detection and ranging (LIDAR) in uncooled direct-gap photodiodes. A theoretical study of degenerate 2PA (D-2PA) in quantum wells, QWs, is presented, along with a new theory of ND 2PA in …

Conservation Laws And Electromagnetic Interactions, Veerachart Kajorndejnukul

Electronic Theses and Dissertations

Aside from energy, light carries linear and angular momenta that can be transferred to matter. The interaction between light and matter is governed by conservation laws that can manifest themselves as mechanical effects acting on both matter and light waves. This interaction permits remote, precise, and noninvasive manipulation and sensing at microscopic levels. In this dissertation, we demonstrated for the first time a complete set of opto-mechanical effects that are based on nonconservative forces and act at the interface between dielectric media. Without structuring the light field, forward action is provided by the conventional radiation pressure while a backward movement …

Photon Statistics In Disordered Lattices, Hasan Kondakci

Electronic Theses and Dissertations

Propagation of coherent waves through disordered media, whether optical, acoustic, or radio waves, results in a spatially redistributed random intensity pattern known as speckle -- a statistical phenomenon. The subject of this dissertation is the statistics of monochromatic coherent light traversing disordered photonic lattices and its dependence on the disorder class, the level of disorder and the excitation configuration at the input. Throughout the dissertation, two disorder classes are considered, namely, diagonal and off-diagonal disorders. The latter exhibits disorder-immune chiral symmetry -- the appearance of the eigenmodes in skew-symmetric pairs and the corresponding eigenvalues in opposite signs. When a disordered …