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Flexible Electrical And Software Programmable Transceivers For Wireless Communications (Feast Ii), Mike Ellinger, James Etters, Eric Juntunen Apr 2003

Flexible Electrical And Software Programmable Transceivers For Wireless Communications (Feast Ii), Mike Ellinger, James Etters, Eric Juntunen

Honors Theses

Flexible Electrical and Software Programmable Transceivers (FEAST) is a project aimed at advancing both research and educational opportunities in wireless communications. The development of high speed analog-to-digital and digital-to-analog converters has enabled the modulation/demodulation of communications signals via real-time data processing. These "software radios" will allow greater flexibility in the reception and transmission of wireless signals. The FEAST wireless transceiver is such a system consisting of analog RF signal down converters and upconverters, high speed analog-to-digital and digital-toanalog converters, hardware digital signal processing IC's and real time software signal processing.

Phase II of the project (FEASTII) project focuses is on …


Improving The Performance Of Single Chip Image Capture Devices, Barbara E. Marino, Robert L. Stevenson Apr 2003

Improving The Performance Of Single Chip Image Capture Devices, Barbara E. Marino, Robert L. Stevenson

Computer Science Faculty Works

Single chip charge-coupled devices (CCDs) coupled with filters for isolating red, green, and blue color content are commonly used to capture color images. While this is more cost effective than multiple chip systems, best results are obtained when full RGB color information is obtained for every point in an image. The process of color subsampling in a single chip system degrades the resulting image data by introducing artifacts such as blurry edges and false coloring. We propose an algorithm for enhancing color image data that were captured with a typical single chip CCD array. The algorithm is based on stochastic …


A Combinatorial Technique For Face Detection Based On Color And Statistical Analysis, Harishwaran Hariharan Apr 2003

A Combinatorial Technique For Face Detection Based On Color And Statistical Analysis, Harishwaran Hariharan

Electrical & Computer Engineering Theses & Dissertations

Automatic detection of faces from video sequences is an important task in security applications. The number, location, size and orientation of human faces in a video frame are unpredictable and can vary from frame to frame. A face detection algorithm for color images in the presence of varying lighting conditions and complexity in background relying upon color and statistical analysis is presented in this thesis. The new method detects skin regions over the entire image and then classifies the skin regions as faces and non-faces. Segmentation of skin regions is performed by a novel color space merging procedure named Integrated …


A Pipelined Architecture For Real Time Correction Of Barrel Distortion In Wide-Angle Camera Images, Hau Trung Ngo Apr 2003

A Pipelined Architecture For Real Time Correction Of Barrel Distortion In Wide-Angle Camera Images, Hau Trung Ngo

Electrical & Computer Engineering Theses & Dissertations

Images captured by wide-angle cameras show barrel type spatial distortion due to wide-angle configuration of the camera lens where image regions farther from the center are compressed in a nonlinear fashion. The barrel distortion correction technique based on least squares estimation attempts to correct a distorted image by expanding it nonlinearly so that straight lines in the object space remain straight in the image space. The intensity value of a pixel in the expanded image is calculated by back mapping its position to the corresponding position in the distorted image and performing linear interpolation on the neighboring pixels. Distorted images …


Analysis Of Ingaassb/Aigaassb Photodetectors For Applications At The 2.0 Micron Wavelengths, Phani Pendyala Apr 2003

Analysis Of Ingaassb/Aigaassb Photodetectors For Applications At The 2.0 Micron Wavelengths, Phani Pendyala

Electrical & Computer Engineering Theses & Dissertations

The study of an InGaAsSb-based heterojunction avalanche photo detector has been carried out for 2-μm applications. A separate absorption and multiplication structure was used because it minimizes the tunneling component of the dark current in the absorption region, and also provides single-carrier injection into the multiplication region. This is a well-known requirement for reducing the multiplication noise. The primary goal was to evaluate the potential of InGaAsSb-AlGaAsSb photo-detectors for photodetection at the two-micron wavelength.

InGaAsSb is a relatively new material, and, therefore, characterization and photodetector response analysis based on this material are not available in the literature. In this thesis …


Adaptive Segmentation Techniques For Object Region Extraction From Images With Complex Lighting Environment, Deepthi P. Valaparla Apr 2003

Adaptive Segmentation Techniques For Object Region Extraction From Images With Complex Lighting Environment, Deepthi P. Valaparla

Electrical & Computer Engineering Theses & Dissertations

Automated image segmentation of objects in complex lighting environments is a difficult task since it is not possible to pre-define a threshold to distinguish the object from the background. It is ascertained that an effective threshold citation for such objects depends on the negative binomial distribution of the object region with respect to the background lighting. Based on this concept, a novel adaptive threshold selection method for automatic segmentation of the lumen region in endoscopic images is presented in this thesis. More precise lumen region and boundary are obtained by an integrated neighborhood search based region growing procedure whose speed …


Blackfingers A Sophisticated Hand Prothesis, Michele Folgheraiter, Giuseppina Gini, Marek Perkowski, Mikhail Pivtoraiko Apr 2003

Blackfingers A Sophisticated Hand Prothesis, Michele Folgheraiter, Giuseppina Gini, Marek Perkowski, Mikhail Pivtoraiko

Electrical and Computer Engineering Faculty Publications and Presentations

Our goal is to develop the low level control system for an artificial hand ”Blackfingers”. Blackfingers was thought to have two main applications: as humanoid robot’s hand or as a human hand prothesis. In this last application our intent is to realize a device more sophisticated respect the actual commerce prothesis. Also in our intention is to use some biological paradigms to create a human like reflex control easy to be interfaced also with the human nervous system. In this paper we illustrate the properties and the morphology of a human like neural reflex controller, used to set the stiffness …


Data Compression Applied To Electric Power Quality Tracking Of Arc Furnace Load, Chi-Jui Wu, Tsu-Hsun Fu Mar 2003

Data Compression Applied To Electric Power Quality Tracking Of Arc Furnace Load, Chi-Jui Wu, Tsu-Hsun Fu

Journal of Marine Science and Technology–Taiwan

The data compression techniques are used to enhance the storage capability of electric power quality instruments in monitoring distorted waveforms of electric arc furnaces. Both voltage flicker in voltage waveforms and harmonic components in current waveforms are major disturbances. The compression approaches by multiresolution analysis developed from the discrete wavelet transform with threshold coding and vector quantization coding are compared. The results from spectrum analysis show high compression ratios while keep low information loss. The error levels between original and reconstructed waveforms are discussed. Field measured waveforms from arc furnace loads are used to show the goodness of the data …


Channel Probing For An Indoor Wireless Communications Channel, Brandon Hunter Mar 2003

Channel Probing For An Indoor Wireless Communications Channel, Brandon Hunter

Theses and Dissertations

The statistics of the amplitude, time and angle of arrival of multipaths in an indoor environment are all necessary components of multipath models used to simulate the performance of spatial diversity in receive antenna configurations. The model presented by Saleh and Valenzuela, was added to by Spencer et. al., and included all three of these parameters for a 7 GHz channel. A system was built to measure these multipath parameters at 2.4 GHz for multiple locations in an indoor environment. Another system was built to measure the angle of transmission for a 6 GHz channel. The addition of this parameter …


Learning States And Rules For Time Series Anomaly Detection, Stan Salvador, Philip K. Chan, John Brodie Mar 2003

Learning States And Rules For Time Series Anomaly Detection, Stan Salvador, Philip K. Chan, John Brodie

Electrical Engineering and Computer Science Faculty Publications

In this paper, we investigate machine learning techniques for discovering knowledge that can be used to monitor the operation of devices or systems. Specifically, we study methods for generating models that can detect anomalies in time series data. The normal operation of a device can usually be characterized in different temporal states. To identify these states, we introduce a clustering algorithm called Gecko that can automatically determine a reasonable number of clusters using our proposed "L" method. We then use the RIPPER classification algorithm to describe these states in logical rules. Finally, transitional logic between the states is added to …


A New Approach To Scalable Lindasystems Based On Swarms, Ronaldo Menezes, Robert Tolksdorf Mar 2003

A New Approach To Scalable Lindasystems Based On Swarms, Ronaldo Menezes, Robert Tolksdorf

Electrical Engineering and Computer Science Faculty Publications

Natural forming multi-agent systems (aka Swarms) have the ability to grow to enormous sizes without requiring any of the agents to oversee the entire system. The success of these systems comes from the fact that agents are simple and the interaction with the environment and neighboring agents is local in nature. In this paper we look at abstractions in the field of swarms and study their applicability in the context of coordination systems. In particular, we focus on the problematic issue of scalability of Linda systems. The purpose of this work is to look at abstractions yielded from observations of …


Designing, Debugging, And Deploying Configurable Computing Machine-Based Applications Using Reconfigurable Computing Application Frameworks, Anthony Lynn Slade Mar 2003

Designing, Debugging, And Deploying Configurable Computing Machine-Based Applications Using Reconfigurable Computing Application Frameworks, Anthony Lynn Slade

Theses and Dissertations

Configurable computing machines (CCMs) offer high-performance application acceleration with custom hardware. They are also dynamically reconfigurable and give significant internal visibility. Such features are useful throughout the design, debug, and deploy stages of CCM-based application development. However traditional, monolithic design tools do not offer adequate support for all of these development stages. This thesis describes a specification for a reconfigurable computing application framework (RCAF) which is more suitable for CCM application development. It also describes an implementation of such an RCAF. This RCAF improves the efficiency of application design and debugging. It also establishes an application architecture framework which helps …


An Advanced Ambiguity Selection Algorithm For Seawinds, David G. Long, David W. Draper Mar 2003

An Advanced Ambiguity Selection Algorithm For Seawinds, David G. Long, David W. Draper

Faculty Publications

SeaWinds on QuikSCAT, a spaceborne Ku-band scatterometer, estimates ocean winds via the relationship between the normalized radar backscatter and the vector wind. Scatterometer wind retrieval generates several possible wind vector solutions or ambiguities at each resolution cell, requiring a separate ambiguity selection step to give a unique solution. In processing SeaWinds on QuikSCAT data, the ambiguity selection is "nudged" or initialized using numerical weather prediction winds. We describe a sophisticated new ambiguity selection approach developed at Brigham Young University (BYU) that does not require nudging. The BYU method utilizes a low-order data-driven Karhunen-Loeve wind field model to promote self-consistency. Ambiguity …


High-Resolution Measurements With A Spaceborne Pencil-Beam Scatterometer Using Combined Range/Doppler Discrimination Techniques, David G. Long, Michael W. Spencer, Wu-Yang Tsai Mar 2003

High-Resolution Measurements With A Spaceborne Pencil-Beam Scatterometer Using Combined Range/Doppler Discrimination Techniques, David G. Long, Michael W. Spencer, Wu-Yang Tsai

Faculty Publications

Conically scanning pencil-beam scatterometer systems, such as the SeaWinds radar, constitute an important class of instruments for spaceborne climate observation. In addition to ocean winds, scatterometer data are being applied to a wide range of land and cryospheric applications. A key issue for future scatterometer missions is improved spatial resolution. Pencil-beam scatterometers to date have been real-aperture systems where only range discrimination is used, resulting in a relatively coarse resolution of approximately 25 km. In this paper, the addition of Doppler discrimination techniques is proposed to meet the need for higher resolution. The unique issues associated with the simultaneous application …


Theoretical Analysis Of Information Watermarking In Wavelet-Based Video Compression, Brendan K. Casey Mar 2003

Theoretical Analysis Of Information Watermarking In Wavelet-Based Video Compression, Brendan K. Casey

Theses and Dissertations

Embedding audio bits into images for transmission of video data alleviates the synchronization problem common in video transmission techniques. We continue work combining audio or other information bits and images into one file using digital watermarking techniques to correct the synchronization problem. The system compresses the file by using wavelet image coefficients and implementing bit plane coding. Our research encompasses incorporating five free variables into the watermark/compression technique. These variables are watermark robustness, number of coding iterations, number of image coefficients, number of watermarked information bits, and number of watermarked error correcting bits. By altering these variables, four measurements of …


Ultra Wide Band Multiple Access Performance Using Th-Ppm And Ds-Bpsk Modulations, Courtney M. Canadeo Mar 2003

Ultra Wide Band Multiple Access Performance Using Th-Ppm And Ds-Bpsk Modulations, Courtney M. Canadeo

Theses and Dissertations

The increasing demand for portable, high data rate communications has focused much attention on wireless technology. Ultra Wide Band (UWB) waveforms have the ability to deliver megabits of information while maintaining low average power consumption. In accordance with recent FCC ruling, UWB systems are now allowed to operate in the unlicensed spectrum of 3.1 to 10.6 GHz, motivating renewed interest in the forty year old concept of impulse radio. Gaussian monocycles produce UWB waveforms occupying large bandwidths with multiple access (MA) capability enabled by spread spectrum techniques. Time Hopping (TH) and Direct Sequence (DS) modulations are considered here for UWB …


Using The Gps To Improve Trajectory Position And Velocity Determination During Real-Time Ejection Seat Design, Test And Evaluation, Christina G. Schutte Mar 2003

Using The Gps To Improve Trajectory Position And Velocity Determination During Real-Time Ejection Seat Design, Test And Evaluation, Christina G. Schutte

Theses and Dissertations

Test and evaluation of the United States Air Force’s latest aircraft escape system technology requires accurate position and velocity profiles during each test to determine the relative positions between the aircraft, ejection seat, manikin and the ground. Current rocket sled testing relies on expensive ground based multiple camera systems to determine the position and velocity profiles. While these systems are satisfactory at determining seat and manikin trajectories for sled testing, their accuracy decreases when they are used for in-flight testing, especially at high altitudes. This research presents the design and test results from a new GPS-based system capable of monitoring …


Analysis Of Broadband Higp-Impedance Ground Plane Antenna Designs, James W. Stewart Mar 2003

Analysis Of Broadband Higp-Impedance Ground Plane Antenna Designs, James W. Stewart

Theses and Dissertations

This research ties together computational and experimental analysis of two types of high-impedance ground plane (HIGP) antennas. One type of antenna consists of a proposed two-layer design. The structure consists of a bowtie antenna mounted over the surface of a HIGR The proposed structure was intended to achieve a resonant frequency of 3 GHz and a bandwidth of 48%; however, a design error results in a significant mismatch in operating bands between the antenna and HIGR Experiment results indicate the structure performs poorly across the entire measured band of 2-5 GHz. A new two-layer design is developed and presented. The …


Feature Guided Image Registration Applied To Phase And Wavelet-Base Optic Flow, Kate R. Duffy Mar 2003

Feature Guided Image Registration Applied To Phase And Wavelet-Base Optic Flow, Kate R. Duffy

Theses and Dissertations

Optic Flow algorithms are useful in problems such as computers vision, navigational systems, and robotics. However, current algorithms are computationally expensive or lack the accuracy to be effective compared with traditionally navigation systems. Recently, lower accuracy inertial navigation systems (INS) based on Microelectromechanical systems (MEMS) technology have been proposed to replace more accurate traditional navigation systems.


Gaussian Mixture Reduction Of Tracking Multiple Maneuvering Targets In Clutter, Jason L. Williams Mar 2003

Gaussian Mixture Reduction Of Tracking Multiple Maneuvering Targets In Clutter, Jason L. Williams

Theses and Dissertations

The problem of tracking multiple maneuvering targets in clutter naturally leads to a Gaussian mixture representation of the Provability Density Function (PDF) of the target state vector. State-of-the-art Multiple Hypothesis Tracking (MHT) techniques maintain the mean, covariance and probability weight corresponding to each hypothesis, yet they rely on ad hoc merging and pruning rules to control the growth of hypotheses.


Fast Compression Of Imagery With High Frequency Content, D. Scott Anderson Mar 2003

Fast Compression Of Imagery With High Frequency Content, D. Scott Anderson

Theses and Dissertations

Image compression is an active area due to the many applications involving electronic media. Much research has been focused on image quality versus bit rate and/or algorithm speed. Here, we seek an effective image coder with a weighted constraint on speed. However, the compression must not taint the quality of impulsive features on the image. Moreover, the camera is operated in a mode that creates a dominant fixed pattern noise across the image array, degrading visual quality and disrupting compression performance. We propose a method that efficiently compresses such an image. We begin by characterizing and removing the fixed pattern …


Development Of Variable Slope Piecewise-Based Brown Symbols For Application To Nonlinear Ambiguity Suppression, John Kurian Mar 2003

Development Of Variable Slope Piecewise-Based Brown Symbols For Application To Nonlinear Ambiguity Suppression, John Kurian

Theses and Dissertations

In 1962, Palermo used two conjugate Linear Frequency Modulated (LFM) pulses to demonstrate a Non-linear Ambiguity Suppression (NLAS) technique to reduce ambiguous energy in radar returns. Using conjugate LFM pulse coding does not readily extend to larger symbol families and thus is severely limited for M-channel (M> 2) NLAS applications. Larger families of optimal mutually dispersible codes with bigger time bandwidth products are needed to achieve the desired M-fold range ambiguity reduction. Using correlation function the time duration as an optimization metric, the recently proposed Brown's theorem formulates a deterministic process for designing optimal mutually dispersible symbol sets of arbitrary …


Redundant Discrete Wavelet Transform Based Super-Resolution Using Sub-Pixel Image Registration, Daniel L. Ward Mar 2003

Redundant Discrete Wavelet Transform Based Super-Resolution Using Sub-Pixel Image Registration, Daniel L. Ward

Theses and Dissertations

The limited resolution of video imagery taken by aircraft, over geographical areas of interest, hinders the accurate extraction of useful information. The frame resolution of the video is determined by the camera that created it. Information exists about the camera which can be used to increase frame resolution beyond the resolution capability of the camera. This is achieved by a process called super-resolution, which uses multiple low-resolution video frames to create one high-resolution image.


Evaluating The Performance Of Multiple Classifier Systems: A Matrix Algebra Representation Of Boolean Fusion Rules, Justin M. Hill Mar 2003

Evaluating The Performance Of Multiple Classifier Systems: A Matrix Algebra Representation Of Boolean Fusion Rules, Justin M. Hill

Theses and Dissertations

Given a finite collection of classifiers one might wish to combine, or fuse, the classifiers in hopes that the multiple classifier system (MCS) will perform better than the individuals. One method of fusing classifiers is to combine their final decision using Boolean rules (e.g., a logical OR, AND, or a majority vote of the classifiers in the system). An established method for evaluating a classifier is measuring some aspect of its Receiver Operating Characteristic (ROC) curve, which graphs the trade-off between the conditional probabilities of detection and false alarm. This work presents a unique method of estimating the performance of …


Total Dose Effects Of Ionizing And Non-Ionizing Radiation On Piezoresistive Pressure Transducer Chips, Samuel J. Willmon Mar 2003

Total Dose Effects Of Ionizing And Non-Ionizing Radiation On Piezoresistive Pressure Transducer Chips, Samuel J. Willmon

Theses and Dissertations

The effects of ionizing and non ionizing radiation on the resistivity of silicon based, piezoresistive bulk micro-machined chips from pressure transducers were examined. Standard current-voltage (I-V) measurements were taken in-situ and post-irradiation during isothermal annealing at room temperature. One group of chips was irradiated to a maximum total gamma dose of lMrad(Si) in the 11,000 Ci (60) Co gamma cell at Ohio State University. The second group of chips was irradiated at the Ohio State University Research Reactor facility to a maximum total neutron dose of 4 Mrad(Si) using beam port Hi. The resistivity was shown to decrease during gamma …


Quantum Mechanical Calculations Of Monoxides Of Silicon Carbide Molecules, John W. Roberts Jr. Mar 2003

Quantum Mechanical Calculations Of Monoxides Of Silicon Carbide Molecules, John W. Roberts Jr.

Theses and Dissertations

Modern semiconductor devices are principally made using the element silicon. In recent years, silicon carbide (SiC), with its wide band-gap, high thermal conductivity, and radiation resistance, has shown prospects as a semiconductor material for use in high temperature and radiation environments such as jet engines and satellites. A limiting factor in the performance of many SiC semiconductor components is the presence of lattice defects formed at oxide dielectric junctions during processing. Recent theoretical work has used small quantum mechanical systems embedded in larger molecular mechanics structures to attempt to better understand SiC surfaces and bulk materials and their oxidation. This …


Efficient Decomposition Of Large Fuzzy Functions And Relations, Paul Burkey, Marek Perkowski Mar 2003

Efficient Decomposition Of Large Fuzzy Functions And Relations, Paul Burkey, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

This paper presents a new approach to decomposition of fuzzy functions. A tutorial background on fuzzy logic representations is first given to emphasize next the simplicity and generality of this new approach. Ashenhurst-like decomposition of fuzzy functions was discussed in [3] but it was not suitable for programming and was not programmed. In our approach, fuzzy functions are converted to multiple-valued functions and decomposed using an mv decomposer. Then the decomposed multiple-valued functions are converted back to fuzzy functions. This approach allows for Curtis-like decompositions with arbitrary number of intermediate fuzzy variables, that have been not presented for fuzzy functions …


A New Temporal Pattern Identification Method For Characterization And Prediction Of Complex Time Series Events, Richard J. Povinelli, Xin Feng Mar 2003

A New Temporal Pattern Identification Method For Characterization And Prediction Of Complex Time Series Events, Richard J. Povinelli, Xin Feng

Electrical and Computer Engineering Faculty Research and Publications

A new method for analyzing time series data is introduced in this paper. Inspired by data mining, the new method employs time-delayed embedding and identifies temporal patterns in the resulting phase spaces. An optimization method is applied to search the phase spaces for optimal heterogeneous temporal pattern clusters that reveal hidden temporal patterns, which are characteristic and predictive of time series events. The fundamental concepts and framework of the method are explained in detail. The method is then applied to the characterization and prediction, with a high degree of accuracy, of the release of metal droplets from a welder. The …


The Effects Of Gps M-Code On Radar Detection, Jae K. Yang Mar 2003

The Effects Of Gps M-Code On Radar Detection, Jae K. Yang

Theses and Dissertations

The GPS system is undergoing a modernization effort which will add several new signals to be placed at the L1, L2, and L5 frequency bands. One of the signals to be placed on L2 is a new military code (M-code) which may be transmitted at a higher power level than current GPS signals. Other users of the L2 frequency band are concerned with the potential interference that may be caused by the increase in power of the GPS signal. One particular use of the 1215-1400 MHz frequency band is Air Traffic Control (ATC) radar applications.


Satisficing Applied To Simulated Soccer, Jay Packard Feb 2003

Satisficing Applied To Simulated Soccer, Jay Packard

Theses and Dissertations

Satisficing was introduced by the economist Herbert Simon to allow for decisions that are "good enough" when there are insufficient computational resources and knowledge to obtain the optimal outcome. Autonomous multi-agent systems often require such decision making because of the complexity and unknown factors present in such an environment. Satisficing has been extended significantly by Wynn Stirling. Through extended satisficing, he has departed from conventional approaches to autonomous multi-agent systems, based as they usually are on the assumption that each participant is motivated exclusively by its own self interest, and will therefore attempt to maximize its benefit, regardless of the …