Digital Commons Network^™

Advanced Algorithms For Vlsi: Statistical Circuit Optimization And Cyclic Circuit Analysis, Osama Neiroukh

Dissertations and Theses

This work focuses on two emerging fields in VLSI. The first is use of statistical formulations to tackle one of the classical problems in VLSI design and analysis domains, namely gate sizing. The second is on analysis of nontraditional digital systems in the form of cyclic combinational circuits.

In the first part, a new approach for enhancing the process-variation tolerance of digital circuits is described. We extend recent advances in statistical timing analysis into an optimization framework. Our objective is to reduce the performance variance of a technology-mapped circuit where delays across elements are represented by random variables which capture …

Channel Modeling For Vehicle-To-Vehicle Communications, David W. Matolak

Faculty Publications

Physical layer channel modeling is critical for design and performance evaluation at multiple layers of the communications protocol stack. In this article we describe and provide results for modeling vehicle-to-vehicle (V2V) wireless channels. V2V settings produce some unique conditions, and due to these conditions, V2V channels often exhibit greater dynamics than many conventional channels and, in addition, can also exhibit more severe fading. Thus, new channel models are needed to characterize this setting in order to evaluate contending transmission schemes and aid in V2V communication system design. A brief review of key statistical channel parameters is provided. Then both analytical …

Quadrotor Dynamics And Control Rev 0.1, Randal Beard

Faculty Publications

These notes outline quadrotor dynamics, state estimation, and control using a camera as the primary sensor.

Measurement Of Absolute Argon Excited State Populations And Electron Energy Distribution Functions In An Ar-A-Si Plasma, Katherine Herring

Electrical Engineering Undergraduate Honors Theses

Deposition systems utilizing plasma are used for a variety of tasks, including tool coatings and creating thin-film materials. In order to have repeatable results, the internal conditions of a plasma chamber need to be known. This project centered on the use of data from optical emissions and a Langmuir probe from an argon plasma amorphous silicon depositing system. An electron energy distribution function (EEDF) was obtained from manipulation of the Langmuir probe data. This EEDF was then input to an argon collisional-radiative model (CRM) to obtain the electron population of the 4p level of the argon plasma. Through an absolute …

A Timer Module For An 8051 Microcontroller, Troy England

Electrical Engineering Undergraduate Honors Theses

A timer module for an 8051 Microcontroller is designed from the ground up. It could potentially be integrated into a larger 8051 for use in lunar and Martian missions. It follows through a synchronous digital design flow from HDL code through layout verification. The timer shows functionality at 100MHz with some minor glitches.

Algorithm Development For Column Water Vapor Retrieval Using The Sun And Aureole Measurement (Sam) Sensor, Joshua Bruce Williams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To understand and model the energetics of the Sun-Earth connection, measurements of specific atmospheric molecules are beneficial. The objective is to formulate an algorithm to derive temporally varying atmospheric water vapor concentrations as functions of altitude, latitude, and longitude from solar irradiance absorption measurements. The Visidyne SAM (Sun and Aureole Measurement) instrument, which studies the size and distribution of cloud particles, was used to obtain the experimental data. By introducing a spectrometer to the SAM instrument, column water vapor is produced as part of the data product. A new model optimized algorithm is developed and tested versus existing algorithms. Through …

A Ladar-Based Pose Estimation Algorithm For Determining Relative Motion Of A Spacecraft For Autonomous Rendezvous And Dock, Ronald Christopher Fenton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Future autonomous space missions will require autonomous rendezvous and docking operations. The servicing spacecraft must be able to determine the relative 6 degree-of-freedom (6 DOF) motion between the vehicle and the target spacecraft. One method to determine the relative 6 DOF position and attitude is with 3D ladar imaging. Ladar sensor systems can capture close-proximity range images of the target spacecraft, producing 3D point cloud data sets. These sequentially collected point-cloud data sets were then registered with one another using a point correspondence-less variant of the Iterative Closest Points (ICP) algorithm to determine the relative 6 DOF displacements. Simulation experiments …

Algorithm Development Of The Aglite-Lidar Instrument, Christian Marchant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Particulate emissions from agricultural operations are increasingly receiving attention from regulatory bodies as a potential source of air pollution. The Space Dynamics Laboratory (SDL) has developed the Aglite system, a suite of instruments including a lidar that is capable of measuring particulate emission levels from agricultural facilities. This system provides a novel method of measuring particulate mass (PM) pollution, allowing measurements to be taken of diverse types of facilities with high temporal and spatial resolution. This high resolution allows for the measurement of emission levels generated by specific activities, fostering the development and determination of best management practices.

The Aglite …

Improved Closed-Form Bounds On The Performance Of Convolutional Codes With Correlated Rayleigh Fading, Dwight Hutchenson

All Theses

New bounds on the probability of bit error are presented for a coded communication system with binary antipodal modulation and soft-decision maximum-likelihood decoding over a correlated Rayleigh-fading channel. The bounds are closed-form expressions in terms of the code's transfer function; they are illustrated by considering a system using convolutional encoding. A long-standing conjecture regarding the worst-case error event in correlated Rician fading is proven for the special case of correlated Rayleigh fading, and it is used in the development of some of the new bounds. The bounds are shown to be tighter than previously developed closed-form bounds for communications using …

A Systems Approach To The Design Of A Two Dimensional Cell Printer, Albert Hill

All Theses

Tissue engineering research has the potential to improve the current opportunities for replacement organs and tissues. Precise placement of cells has proven difficult in the early stages of this research. Bioprinting is an important research area that has the potential to accurately position cells and biological materials for tissue engineering. This paper describes the attempt to obtain micrometer accuracy in the placement of cells using a systems approach and technology derived from the Hewlett Packard 500 series of printers and their cartridges the HP26 series. The paper discusses the research and design of a custom printing system that allows control …

Susceptibility Scanning As Failure Analysis Tool For System-Level Electrostatic Discharge (Esd) Problems, Giorgi Muchaidze, Jayong Koo, Qing Cai, Tun Li, Lijun Han, Andrew Martwick, Kai Wang, Jin Min, James L. Drewniak, David Pommerenke

Electrical and Computer Engineering Faculty Research & Creative Works

Susceptibility scanning is an increasingly adopted method for root cause analysis of system-level immunity sensitivities. It allows localizing affected nets and integrated circuits (ICs). Further, it can be used to compare the immunity of functionally identical or similar ICs or circuit boards. This paper explains the methodology as applied to electrostatic discharge and provides examples of scan maps and signals probed during immunity scanning. Limitations of present immunity analysis methods are discussed.

Using Tem Cell Measurements To Estimate The Maximum Radiation From Pcbs With Cables Due To Magnetic Field Coupling, Shaowei Deng, Todd H. Hubing, Daryl G. Beetner

Electrical and Computer Engineering Faculty Research & Creative Works

Common-mode currents can be induced on cables attached to printed circuit boards (PCBs) due to electric and magnetic field coupling. This paper describes a technique for using transverse electromagnetic (TEM) cell measurements to obtain an effective common-mode voltage (or magnetic moment) that quantifies the ability of traces and integrated circuits on PCBs to drive common-mode currents onto cables due to magnetic field coupling. This equivalent common-mode voltage can be used to reduce the complexity of full-wave models that calculate the radiated emissions from a system containing the board. It can also be used without full-wave modeling to provide a …

A Novel 24 Ghz One-Shot, Rapid And Portable Microwave Imaging System, Mohammad Tayeb Ahmad Ghasr, Mohamed A. Abou-Khousa, Sergey Kharkovsky, R. Zoughi, David Pommerenke

Electrical and Computer Engineering Faculty Research & Creative Works

Development of microwave and millimeter wave imaging systems has received significant attention in the past decade. Signals at these frequencies penetrate inside of dielectric materials and have relatively small wavelengths. Thus, imaging systems at these frequencies can produce images of the dielectric and geometrical distributions of objects. Although there are many different approaches for imaging at these frequencies, they each have their respective advantageous and limiting features (hardware, reconstruction algorithms). One method involves electronically scanning a given spatial domain while recording the coherent scattered field distribution from an object. Consequently, different reconstruction or imaging techniques may be used to produce …

A Variable Partitioning Strategy For The Multirate Method In Power Systems, Jingjia Chen, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

An application of the multirate method to differential and algebraic equations (DAEs) is discussed in this paper. Based on the specific formulation of the power systems algebraic equations, an effective algebraic variable partitioning strategy is developed and implemented. The application of the partitioning strategy to an example power system provides validation of the proposed partitioning strategy in terms of speed-up and accuracy.

A Review Of Variable Valve Timing Devices, Paul Shelton

Mechanical Engineering Undergraduate Honors Theses

Variable valve timing (VVT) has evolved from simple, manual controlled engine management to automatic, electronic works of engineering. Starting from the need for more power and extending into fuel efficiency and low emissions, VVT has evolved from the constant changing of needs. This paper summarizes various devices used to control the timing of valves from the early 1920s up until 2007.

A Two-Degree-Of-Freedom Time-Optimal Solution For Hard Disk Drive Servo Problems, Shaohua Hu, Zhiqiang Gao

Electrical and Computer Engineering Faculty Publications

This paper deals with the hard disk drive (HDD) servo problems. A novel discrete time-optimal control solution is proposed in a two-degree-of-freedom (2DOF) structure, employing both the feedback and feedforward controllers. The time-optimal feedback controller, derived from a simple, double integral plant model, shows remarkable robustness and disturbance rejection in the presence of resonant modes, measurement noises and position and torque disturbances. It eliminates the needs for two separate controllers for track-seeking and track-following operations. The proposed feedforward controller in this 2DOF structure proves to be quite beneficial in reducing the …

Sampling Frequencies Ratio Estimation And Symbol Timing Recovery For Baseband Binary Pulse Amplitude Modulation, Ana A. Paniagua Rodriguez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The original intent of this project was to perform real time digital communications between a personal computer (PC) as the transmitter and a digital signal processor (DSP) as the receiver using the audio band analog channel. Although transmitter and receiver were both designed with baseband binary Pulse Amplitude Modulation (PAM), a low data rate and a sampling rate of 8 kilohertz, it was not possible to achieve communication between the two with traditional synchronization algorithms because of large differences in sampling clock frequencies. This thesis explores the theory and results of implementing digital communications between systems with differenet sampling frequencies. …

A Stabilizing, High-Performance Controller For Input Series-Output Parallel Converters, Jonathan W. Kimball, Joseph T. Mossoba, Philip T. Krein

Electrical and Computer Engineering Faculty Research & Creative Works

A form of sensorless current mode (SCM) control stabilizes sharing in multiphase input-series-output-parallel (ISOP) dc-dc converter topologies. Previously, ISOP converters have been proposed to reduce the voltage and current ratings of switching devices. Since the inputs are all connected in series, each phase need only be rated for a fraction of the total input voltage. Voltage and current sharing are key - if there is any phase-to-phase imbalance, the system benefits are substantially reduced. In the present work, a simple SCM controller is shown to guarantee stable sharing. Each phase acts independently on the same output reference and desired input …

Channel Estimation For Ofdm Systems In The Presence Of Carrier Frequency Offset And Phase Noise, Jun Tao, Jingxian Wu, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

Channel estimation for orthogonal frequency division multiplexing (OFDM) system at the presence of carrier frequency offset (CFO) and phase noise is discussed in this paper. A CFO estimation algorithm is developed by exploiting the time-frequency structure of training symbols, and it provides a very accurate estimation of CFO at the presence of both unknown frequency selective fading and phase noise. Based on the estimated CFO, the phase noise and frequency selective fading are jointly estimated by employing the maximum a posteriori (MAP) criterion. Specifically, the fading channel is estimated in the form of frequency domain channel transfer function (CTF). The …

Channel Equalization And Symbol Detection For Single Carrier Broadband Mimo Systems With Multiple Carrier Frequency Offsets, Chengshan Xiao, Y. Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

We consider the frequency-domain channel equalization and symbol detection of multiple input multiple output (MIMO) single-carrier broadband wireless system in the presence of severe frequency-selective channel fading and multiple unknown carrier frequency offsets (CFOs). We show that the constellation of the equalized data is rotating due to multiple CFOs, therefore, the equalized data can not be reliably detected without removing the rotating phases caused by the multiple unknown CFOs. Instead of estimating the CFOs, we propose a method to estimate the rotating phases caused by multiple CFOs, remove the rotating phases from the equalized data, and perform symbol detection. Numerical …

Protocols For Dynamic Spectrum Access, Thomas Royster

All Dissertations

Protocols for modulation selection, initial transmitter power adjustment, modulation and coding adaptation, and transmitter power adaptation are presented. Most adaptive protocols in the literature are for full-duplex communication and they require channel estimation (e.g., using training symbols); however, our protocols are for half-duplex packet radios and they do not require estimation of the channel for adaptation. Instead, our protocols are driven by statistics that can be derived from the receiver's demodulator or decoder. We present the protocols in the context of their application to dynamic spectrum access networks. Our protocols are designed for adaptive radios, of which software-defined radios and …

Design And Implementation Of Digital Signal Processing Hardware For A Software Radio Reciever, Jake Talbot

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This project summarizes the design and implementation of field programmable gate array (FPGA) based digital signal processing (DSP) hardware meant to be used in a software radio system. The filters and processing were first designed in MATLAB and then implemented using very high speed integrated circuit hardware description language (VHDL). Since this hardware is meant for a software radio system, making the hardware flexible was the main design goal. Flexibility in the FPGA design was reached using VHDL generics and generate for loops. The hardware was verified using MATLAB generated signals as stimulus to the VHDL design and comparing the …

Data Mining Techniques For Fraud Detection, Rekha Bhowmik

Annual ADFSL Conference on Digital Forensics, Security and Law

The paper presents application of data mining techniques to fraud analysis. We present some classification and prediction data mining techniques which we consider important to handle fraud detection. There exist a number of data mining algorithms and we present statistics-based algorithm, decision tree-based algorithm and rule-based algorithm. We present Bayesian classification model to detect fraud in automobile insurance. Naïve Bayesian visualization is selected to analyze and interpret the classifier predictions. We illustrate how ROC curves can be deployed for model assessment in order to provide a more intuitive analysis of the models.

Keywords: Data Mining, Decision Tree, Bayesian Network, ROC …

Stabilization And Control Of A Quad-Rotor Micro-Uav Using Vision Sensors, Spencer G. Fowers

Theses and Dissertations

Quad-rotor micro-UAVs have become an important tool in the field of indoor UAV research. Indoor flight poses problems not experienced in outdoor applications. The ability to be location- and movement-aware is paramount because of the close proximity of obstacles (walls, doorways, desks). The Helio-copter, an indoor quad-rotor platform that utilizes a compact FPGA board called Helios has been developed in the Robotic Vision Lab at Brigham Young University. Helios allows researchers to perform on-board vision processing and feature tracking without the aid of a ground station or wireless transmission. Using this on-board feature tracking system a drift stabilization control system …

Real-Time Implementation Of Vision Algorithm For Control, Stabilization, And Target Tracking For A Hovering Micro-Uav, Beau J. Tippetts

Theses and Dissertations

A lightweight, powerful, yet efficient quad-rotor platform was designed and constructed to obtain experimental results of completely autonomous control of a hovering micro-UAV using a complete on-board vision system. The on-board vision and control system is composed of a Helios FPGA board, an Autonomous Vehicle Toolkit daughterboard, and a Kestrel Autopilot. The resulting platform is referred to as the Helio-copter. An efficient algorithm to detect, correlate, and track features in a scene and estimate attitude information was implemented with a combination of hardware and software on the FPGA, and real-time performance was obtained. The algorithms implemented include a Harris feature …

Real-Time Plasma Controlled Chemistry In A Two-Frequency, Confined Plasma Etcher, Vladimir Milosavljevic, Albert R. Ellingboe, Cezar Gaman, John V. Ringwood

Articles

The physics issues of developing model-based control of plasma etching are presented. A novel methodology for incorporating real-time model-based control of plasma processing systems is developed. The methodology is developed for control of two dependent variables (ion flux and chemical densities) by two independent controls (27 MHz power and O2flow). A phenomenological physics model of the nonlinear coupling between the independent controls and the dependent variables of the plasma is presented. By using a design of experiment, the functional dependencies of the response surface are determined. In conjunction with the physical model, the dependencies are used to deconvolve the sensor …

Measurement Of Oxygen Saturation In The Retina With A Spectroscopic Sensitive Multi Aperture Camera, Jessica C. Ramella-Roman, Scott A. Mathews, Haripriya Kandimalla, Afshin Nabili, Donald D. Duncan, Salvatore A. D'Anna, Syed M. Shah, Quan D. Nguyen

Electrical and Computer Engineering Faculty Publications and Presentations

We introduce a new multi aperture system capable of capturing six identical images of the human fundus at six different spectral bands. The system is based on a lenslet array architecture and is well suited for spectroscopy application. The multi-aperture system was interfaced with a fundus camera to acquire spectroscopic sensitive images of the retina vessel and ultimately to calculate oxygen saturation in the retina in vivo. In vitro testing showed that the system is able to accurately reconstruct curves of partially oxygenated hemoglobin. In vivo testing on healthy volunteers was conducted and yielded results of oxygen saturation similar to …

Parallel Implementation Of High-Speed, Phase Diverse Atmospheric Turbulence Compensation Method On A Neural Network-Based Architecture, William W. Arrasmith, Sean F. Sullivan

Electrical Engineering and Computer Science Faculty Publications

Phase diversity imaging methods work well in removing atmospheric turbulence and some system effects from predominantly near-field imaging systems. However, phase diversity approaches can be computationally intensive and slow. We present a recently adapted, high-speed phase diversity method using a conventional, software-based neural network paradigm. This phase-diversity method has the advantage of eliminating many time consuming, computationally heavy calculations and directly estimates the optical transfer function from the entrance pupil phases or phase differences. Additionally, this method is more accurate than conventional Zernike-based, phase diversity approaches and lends itself to implementation on parallel software or hardware architectures. We use computer …

Subsidence Measurement And Dsm Extraction Of Ifsar Data Using Anisotropic Diffusion And Wavelet Denoising Filters, Kenneth Sartor, Josef De Vaughn Allen, Emile Ganthier, Mark Rahmes, Gnana Bhaskar Tenali, Samuel Peter Kozaitis

Electrical Engineering and Computer Science Faculty Publications

The most commonly used smoothing algorithms for complex data processing are low pass filters. Unfortunately, an undesired side effect of the aforementioned techniques is the blurring of scene discontinuities in the interferogram. For Digital Surface Map (DSM) extraction and subsidence measurement, the smoothing of the scene discontinuities can cause inaccuracy in the final product. Our goal is to perform spatially non-uniform smoothing to overcome the aforementioned disadvantages. We achieve this by using an Anisotropic Non-Linear Diffuser (ANDI). Here, in this paper we will show the utility of ANDI filtering on simulated and actual Interferometric Synthetic Aperture Radar (IFSAR) data for …

Design Of Radio-Frequency Filters And Oscillators In Deep-Submicron Cmos Technology, Haiqiao Xiao

Dissertations and Theses

Radio-frequency filters and oscillators are widely used in wireless communication and high-speed digital systems, and they are mostly built on passive integrated inductors, which occupy a relative large silicon area. This research attempted to implement filters and oscillators operating at 1-5 GHz using transistors only, to reduce the circuits’ area. The filters and oscillators are designed using active inductors, based on the gyrator principle; they are fabricated in standard digital CMOS technology to be compatible with logic circuits and further lower the cost. To obtain the highest operating frequency, only parasitic capacitors were used.

Two new active-inductor circuits are derived …