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Digital Fingerprinting Of Field Programmable Gate Arrays, James W. Crouch Mar 2008

Digital Fingerprinting Of Field Programmable Gate Arrays, James W. Crouch

Theses and Dissertations

Commercial off-the-shelf (COTS) component usage is becoming more prevalent in military applications due to current Department of Defense (DoD) policies. The easy accessibility of COTS will give reverse engineers a higher probability of successfully tampering, coping, or reverse engineering circuits that contain critical capabilities. To prevent this and verify the trustworthiness of hardware, circuit identification tags or serials numbers can be used. However, these values can be easily obtained and forged. To protect critical DoD technologies from possible exploitation, there is an urgent need for a reliable method to confirm a circuit’s identity using a set of unique unforgettable metrics. …

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Design And Optimization Of Broadband High Impedance Ground Planes (Higp) For Surface Mount Antennas, Murat Dogrul Mar 2008

Design And Optimization Of Broadband High Impedance Ground Planes (Higp) For Surface Mount Antennas, Murat Dogrul

Theses and Dissertations

Gain and bandwidth metrics of broad-band low-profile antennas severely deteriorate when they are placed conformally onto the conductive skins of air, sea, and ground platforms. This detrimental effect is primarily due to out-of-phase reflections from the conductive body interfering with the antenna’s self radiation. Furthermore, lateral waves launched by the antenna couple into the thin substrate placed between the antenna and the platform, giving rise to surface waves resulting in significant diffraction from the edges of the substrate. To remedy these two major mechanisms degrading antenna performance, high impedance ground planes (HIGP) were designed. HIGPs made of a 2-dimensional periodic …

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Characterization And Implementation Of A Real-World Target Tracking Algorithm On Field Programmable Gate Arrays With Kalman Filter Test Case, Benjamin D. Hancey Mar 2008

Characterization And Implementation Of A Real-World Target Tracking Algorithm On Field Programmable Gate Arrays With Kalman Filter Test Case, Benjamin D. Hancey

Theses and Dissertations

A one dimensional Kalman Filter algorithm provided in Matlab is used as the basis for a Very High Speed Integrated Circuit Hardware Description Language (VHDL) model. The JAVA programming language is used to create the VHDL code that describes the Kalman filter in hardware which allows for maximum flexibility. A one-dimensional behavioral model of the Kalman Filter is described, as well as a one-dimensional and synthesizable register transfer level (RTL) model with optimizations for speed, area, and power. These optimizations are achieved by a focus on parallelization as well as careful Kalman filter sub-module algorithm selection. Newton-Raphson reciprocal is the …

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Effects Of Multipath And Oversampling On Navigation Using Orthogonal Frequency Division Multiplexed Signals Of Opportunity, Christopher M. Schexnayder Mar 2008

Effects Of Multipath And Oversampling On Navigation Using Orthogonal Frequency Division Multiplexed Signals Of Opportunity, Christopher M. Schexnayder

Theses and Dissertations

The Global Positioning System (GPS) has become the primary system for navigation and precise positioning. GPS has limitations, though, and is not suitable in environments where a line-of-site (LOS) path to multiple satellites is not available. Reliable alternatives need to be developed to provide GPS-like positioning when GPS is unavailable. One such alternative is to use signals of opportunity (SoOP). This concept refers to navigation using signals which inherently exist in the environment and were developed for non-navigation applications. This research focuses on exploiting the Orthogonal Frequency Division Multiplexed (OFDM) signal for the purpose of navigation. An algorithm was developed …

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Hyperspectral-Augmented Target Tracking, Neil A. Soliman Mar 2008

Hyperspectral-Augmented Target Tracking, Neil A. Soliman

Theses and Dissertations

With the global war on terrorism, the nature of military warfare has changed significantly. The United States Air Force is at the forefront of research and development in the field of intelligence, surveillance, and reconnaissance that provides American forces on the ground and in the air with the capability to seek, monitor, and destroy mobile terrorist targets in hostile territory. One such capability recognizes and persistently tracks multiple moving vehicles in complex, highly ambiguous urban environments. The thesis investigates the feasibility of augmenting a multiple-target tracking system with hyperspectral imagery. The research effort evaluates hyperspectral data classification using fuzzy c-means …

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Bottom Profiling By Correlating Beam-Steered Noise Sequences, Chris H. Harrison, Martin Siderius Mar 2008

Bottom Profiling By Correlating Beam-Steered Noise Sequences, Chris H. Harrison, Martin Siderius

Electrical and Computer Engineering Faculty Publications and Presentations

It has already been established that by cross-correlating ambient noisetime series received on the upward and downward steered beams of a drifting vertical array one can obtain a subbottom layer profile. Strictly, the time differential of the cross correlation is the impulse response of the seabed. Here it is shown theoretically and by simulation that completely uncorrelated surfacenoise results in a layer profile with predictable amplitudes proportional to those of an equivalent echo sounder at the same depth as the array. The phenomenon is simulated by representing the sound sources as multiple random time sequences emitted from random locations in …

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Particle Swarm Optimization: Basic Concepts, Variants And Applications In Power Systems, Yamille Del Valle, Ganesh K. Venayagamoorthy, Salman Mohagheghi, Ronald G. Harley, J. C. Hernandez Mar 2008

Particle Swarm Optimization: Basic Concepts, Variants And Applications In Power Systems, Yamille Del Valle, Ganesh K. Venayagamoorthy, Salman Mohagheghi, Ronald G. Harley, J. C. Hernandez

Electrical and Computer Engineering Faculty Research & Creative Works

Many areas in power systems require solving one or more nonlinear optimization problems. While analytical methods might suffer from slow convergence and the curse of dimensionality, heuristics-based swarm intelligence can be an efficient alternative. Particle swarm optimization (PSO), part of the swarm intelligence family, is known to effectively solve large-scale nonlinear optimization problems. This paper presents a detailed overview of the basic concepts of PSO and its variants. Also, it provides a comprehensive survey on the power system applications that have benefited from the powerful nature of PSO as an optimization technique. For each application, technical details that are required …

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Multi-Class Classification Fusion Using Boosting For Identifying Steganography Methods, Benjamin M. Rodriguez, Gilbert L. Peterson Mar 2008

Multi-Class Classification Fusion Using Boosting For Identifying Steganography Methods, Benjamin M. Rodriguez, Gilbert L. Peterson

Faculty Publications

No abstract provided.

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Asymptotic Analysis Of Large Cooperative Relay Networks Using Random Matrix Theory, Husheng Li, Zhu Han, H. Poor Feb 2008

Asymptotic Analysis Of Large Cooperative Relay Networks Using Random Matrix Theory, Husheng Li, Zhu Han, H. Poor

Electrical and Computer Engineering Faculty Publications and Presentations

Cooperative transmission is an emerging communication technology that takes advantage of the broadcast nature of wireless channels. In cooperative transmission, the use of relays can create a virtual antenna array so that multiple-input/multiple-output (MIMO) techniques can be employed. Most existing work in this area has focused on the situation in which there are a small number of sources and relays and a destination. In this paper, cooperative relay networks with large numbers of nodes are analyzed, and in particular the asymptotic performance improvement of cooperative transmission over direction transmission and relay transmission is analyzed using random matrix theory. The key …

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Throughput Constrained And Area Optimized Dataflow Synthesis For Fpgas, Hua Sun Feb 2008

Throughput Constrained And Area Optimized Dataflow Synthesis For Fpgas, Hua Sun

Theses and Dissertations

Although high-level synthesis has been researched for many years, synthesizing minimum hardware implementations under a throughput constraint for computationally intensive algorithms remains a challenge. In this thesis, three important techniques are studied carefully and applied in an integrated way to meet this challenging synthesis requirement. The first is pipeline scheduling, which generates a pipelined schedule that meets the throughput requirement. The second is module selection, which decides the most appropriate circuit module for each operation. The third is resource sharing, which reuses a circuit module by sharing it between multiple operations. This work shows that combining module selection and resource …

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Domino Logic Testing Systems And Methods, Waleed K. Al-Assadi, Pavankumar Chandrasekhar Feb 2008

Domino Logic Testing Systems And Methods, Waleed K. Al-Assadi, Pavankumar Chandrasekhar

Electrical and Computer Engineering Faculty Research & Creative Works

A domino logic test circuit includes a dynamic node, a precharge device for charging the dynamic node, and an output inverter for inverting an output of the dynamic node. A logic network is coupled to the dynamic node for discharging the dynamic node in accordance with logic. A footer device enables and disables the logic network. A keeper device is coupled to the dynamic node for retaining a charge state of the dynamic node while awaiting the logic network to operate in accordance with the logic. A test mode selection device is coupled to the dynamic node and is configured …

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Focal Waveform Of A Prolate-Spheroidal Impulse Radiating Antenna (Ira), Serhat Altunc Feb 2008

Focal Waveform Of A Prolate-Spheroidal Impulse Radiating Antenna (Ira), Serhat Altunc

Electrical and Computer Engineering ETDs

Impulse Radiating Antennas (IRAs) are designed to radiate very fast pulses in a narrow beam with low dispersion and high field amplitude. For this reason they have been used in a variety of applications. IRAs have been developed for the transient far-field region using paraboloidal reflectors. However, in this dissertation we focus on the near field region and develop the field waveform at the second focus of a prolate-spheroidal IRA. Recent research has shown that it is possible to kill certain skin cancers by the application of fast, high-amplitude electric-field pulses. This has been accomplished by the insertion of electrodes …

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Characterization Of Spectral Response Of A Quantum Dots-In-A-Well Infrared Focal Plane Array, Michael Lenz Ii Feb 2008

Characterization Of Spectral Response Of A Quantum Dots-In-A-Well Infrared Focal Plane Array, Michael Lenz Ii

Electrical and Computer Engineering ETDs

Spectral characterization of a novel single bump, two-color InAs/InGaAs quantum dots-in-a-well (DWELL) infrared focal plane array (FPA) was undertaken and reported here. The hypothesis of the study is that the FPA will exhibit bias-tunable spectral response. Broadband and two-color performance measures of the DWELL FPA are discussed and presented. The DWELL structure is a hybrid of a quantum dot (QD) photodetector consisting of an active region composed of InAs quantum dots embedded in InGaAs quantum wells. The DWELL FPA demonstrates mid-wave infrared (MWIR) and long-wave infrared (LWIR) performance believed to be attributed to transitions from bound states in the dot …

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Advanced Parallel Magnetic Resonance Imaging Methods With Applications To Mr Spectroscopic Imaging, Ricardo Otazo Feb 2008

Advanced Parallel Magnetic Resonance Imaging Methods With Applications To Mr Spectroscopic Imaging, Ricardo Otazo

Electrical and Computer Engineering ETDs

Parallel magnetic resonance imaging offers a framework for acceleration of conventional MRI encoding using an array of receiver coils with spatially-varying sensitivities. Novel encoding and reconstruction techniques for parallel MRI are investigated in this dissertation. The main goal is to improve the actual reconstruction methods and to develop new approaches for massively parallel MRI systems that take advantage of the higher information content provided by the large number of small receivers. A generalized forward model and inverse reconstruction with regularization for parallel MRI with arbitrary k-space sub-sampling is developed. Regularization methods using the singular value decomposition of the encoding matrix …

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Stokes Antenna Temperatures, David G. Long, Jeffrey R. Piepmeier, Eni G. Njoku Feb 2008

Stokes Antenna Temperatures, David G. Long, Jeffrey R. Piepmeier, Eni G. Njoku

Faculty Publications

The growing importance of polarimetric radiometers has led to the need for a detailed theory for Stokes antenna temperatures. In this paper, we provide a full Stokes vector formulation of an antenna temperature that accounts for the entire antenna pattern, which includes polarization mixing in the main-beam and sidelobe effects. To derive the Stokes antenna temperatures, we follow the conventional methods in the Earth remote sensing literature while relying on a coherency algebra approach from radio astronomy. Connections and parallels to the conventional approaches are noted along the way. We also introduce generalizations of beam efficiency and cross polarization for …

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Low Complexity Soft-Input Soft-Output Block Decision Feedback Equalization, Jingxian Wu, Y. Rosa Zheng Feb 2008

Low Complexity Soft-Input Soft-Output Block Decision Feedback Equalization, Jingxian Wu, Y. Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

A low complexity soft-input soft-output (SISO) block decision feedback equalizer (BDFE) is presented for turbo equalization. The proposed method employs a sub-optimum sequence-based detection, where the soft-output of the equalizer is calculated by evaluating an approximation of the sequence-based a posteriori probability (APP) of the data symbol. The sequence-based APP approximation is enabled by the adoption of both soft a priori information and soft decision feedback, and it leads to better performance and faster convergence compared to symbol-based detection methods as used by most other low complexity equalizers. The performance and convergence property of the proposed algorithm is analyzed by …

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Embedded Neural Network For Fire Classification Using An Array Of Gas Sensors, Shishir Bashyal, Ganesh K. Venayagamoorthy, Bandana Paudel Feb 2008

Embedded Neural Network For Fire Classification Using An Array Of Gas Sensors, Shishir Bashyal, Ganesh K. Venayagamoorthy, Bandana Paudel

Electrical and Computer Engineering Faculty Research & Creative Works

Fire is one of the most common hazards in US households. In 2006 alone, 2705 people were killed due to fire in building structures. 74% of the deaths result from fires in homes with no smoke alarms or no working smoke alarms while surveys report that 96% of all homes have at least one smoke alarm. This study discusses the development of a fire sensing system that is not only capable of detecting fire in its early stage but also of classifying the fire based on the smell of the smoke in the environment. By using an array of sensors …

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A Suite Of Robust Controllers For The Manipulation Of Microscale Objects, Qinmin Yang, Jagannathan Sarangapani Feb 2008

A Suite Of Robust Controllers For The Manipulation Of Microscale Objects, Qinmin Yang, Jagannathan Sarangapani

Electrical and Computer Engineering Faculty Research & Creative Works

A suite of novel robust controllers is introduced for the pickup operation of microscale objects in a microelectromechanical system (MEMS). In MEMS, adhesive, surface tension, friction, and van der Waals forces are dominant. Moreover, these forces are typically unknown. The proposed robust controller overcomes the unknown contact dynamics and ensures its performance in the presence of actuator constraints by assuming that the upper bounds on these forces are known. On the other hand, for the robust adaptive critic-based neural network (NN) controller, the unknown dynamic forces are estimated online. It consists of an action NN for compensating the unknown system …

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A Reservation-Based Extended Transaction Protocol, Wenbing Zhao, Louise E. Moser, P. Michale Melliar-Smith Feb 2008

A Reservation-Based Extended Transaction Protocol, Wenbing Zhao, Louise E. Moser, P. Michale Melliar-Smith

Electrical and Computer Engineering Faculty Publications

With the advent of the new generation of Internet-based technology, in particular, web services, the automation of business activities that are distributed across multiple enterprises becomes possible. Business activities are different from traditional transactions in that they are typically asynchronous, loosely coupled, and long running. Therefore, extended transaction protocols are needed to coordinate business activities that span multiple enterprises. Existing extended transaction protocols typically rely on compensating transactions to handle exceptional conditions. In this paper, we identify a number of issues with compensation-based extended transaction protocols and describe a reservation-based extended transaction protocol that addresses those issues. Moreover, we define …

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Fault-Tolerant Optimal Neurocontrol For A Static Synchronous Series Compensator Connected To A Power Network, Wei Qiao, Ronald G. Harley, Ganesh K. Venayagamoorthy Feb 2008

Fault-Tolerant Optimal Neurocontrol For A Static Synchronous Series Compensator Connected To A Power Network, Wei Qiao, Ronald G. Harley, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a novel fault-tolerant optimal neurocontrol scheme (FTONC) for a static synchronous series compensator (SSSC) connected to a multimachine benchmark power system. The dual heuristic programming technique and radial basis function neural networks are used to design a nonlinear optimal neurocontroller (NONC) for the external control of the SSSC. Compared to the conventional external linear controller, the NONC improves the damping performance of the SSSC. The internal control of the SSSC is achieved by a conventional linear controller. A sensor evaluation and (missing sensor) restoration scheme (SERS) is designed by using the autoassociative neural networks and particle swarm …

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Projected Cross Point -- A New Average Current-Mode Control Approach, Kai-Tak Wan, Mehdi Ferdowsi Feb 2008

Projected Cross Point -- A New Average Current-Mode Control Approach, Kai-Tak Wan, Mehdi Ferdowsi

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Projected cross point, a new current-mode control technique, is introduced and analyzed in this paper. Despite having an analog nature, the proposed method combines the advantages of both analog and digital control techniques. Unlike the conventional analog control methods, it accurately controls the average value of the inductor current with no need to a current compensator or an external ramp. In addition, while resembling the deadbeat characteristics of digital controllers, projected cross point control does not suffer from computational time delay, limit cycling, and quantization and truncation errors. Dynamic performance of the proposed approach is compared with the existing control …

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A Current-Sensorless Digital Controller For Active Power Factor Correction Control Based On Kalman Filters, Jonathan W. Kimball, Philip T. Krein Feb 2008

A Current-Sensorless Digital Controller For Active Power Factor Correction Control Based On Kalman Filters, Jonathan W. Kimball, Philip T. Krein

Electrical and Computer Engineering Faculty Research & Creative Works

For low-power AC-DC converters, power factor correction (PFC) can be accomplished simply with certain converters operating in discontinuous conduction mode (DCM). At higher power levels, DCM results in higher losses, so most PFC converters use current feedback to actively track the correct current waveshape. This work presents a way to provide PFC control without the current sensor, by replacing the sensor with a Kalman filter, which is essentially a stochastic observer. Experimental results verify its high power factor and low total harmonic distortion (THD).

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Expanded Mathematical Treatment For "Spectral Bias In Adaptive Beamforming With Narrowband Interference'', Brian D. Jeffs, Karl F. Warnick Jan 2008

Expanded Mathematical Treatment For "Spectral Bias In Adaptive Beamforming With Narrowband Interference'', Brian D. Jeffs, Karl F. Warnick

Faculty Publications

This technical note presents extended versions of some mathematical derivations found in the paper Spectral Bias in Adaptive Beamforming with Narrowband Interference which is under review for publication in IEEE Signal Processing Letters. Though the SP Letters paper is self contained and complete, this note provides intermediate steps for some of the equation derivations to assist the interested readers who would like to re-create the results.

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Hardware/Software Codesign In A Compact Ion Mobility Spectrometer Sensor Systemfor Subsurface Contaminant Detection, Sin Ming Loo, Jonathan P. Cole, Molly M. Gribb Jan 2008

Hardware/Software Codesign In A Compact Ion Mobility Spectrometer Sensor Systemfor Subsurface Contaminant Detection, Sin Ming Loo, Jonathan P. Cole, Molly M. Gribb

Electrical and Computer Engineering Faculty Publications and Presentations

A field-programmable-gate-array-(FPGA-) based data acquisition and control system was designed in a hardware/software codesign environment using an embedded Xilinx Microblaze soft-core processor for use with a subsurface ion mobility spectrometer (IMS) system, designed for detection of gaseous volatile organic compounds (VOCs). An FPGA is used to accelerate the digital signal processing algorithms and provide accurate timing and control. An embedded soft-core processor is used to ease development by implementing nontime critical portions of the design in software. The design was successfully implemented using a low-cost, off-the-shelf Xilinx Spartan-III FPGA and supporting digital and analog electronics.

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Reduction Of Efficiency Droop In Ingan Light Emitting Diodes By Coupled Quantum Wells, Xianfeng Ni, Qian Fan, Ryoko Shimada, Ü. Özgür, Hadis Morkoç Jan 2008

Reduction Of Efficiency Droop In Ingan Light Emitting Diodes By Coupled Quantum Wells, Xianfeng Ni, Qian Fan, Ryoko Shimada, Ü. Özgür, Hadis Morkoç

Electrical and Computer Engineering Publications

Light emitting diodes(LEDs) based on InGaN suffer from efficiency droop at current injection levels as low as 50 A cm−2. We investigated multiple quantum wellInGaNLEDs with varying InGaN barrier thicknesses (3–12 nm) emitting at ∼400–410 nm to investigate the effect of hole mass and also to find out possible solutions to prevent the efficiency droop. In LEDs with electron blocking layers, when we reduced the InGaN barriers from 12 to 3 nm, the current density for the peak or saturation of external quantum efficiency increased from 200 to 1100 A cm−2 under pulsed injection conditions, which eliminates the heating effects …

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Influence Of Fiber Manufacturing Tolerances On The Spectral Response Of A Bend Loss Based All-Fiber Edge Filter, Pengfei Wang, Gerald Farrell, Yuliya Semenova, Ginu Rajan Jan 2008

Influence Of Fiber Manufacturing Tolerances On The Spectral Response Of A Bend Loss Based All-Fiber Edge Filter, Pengfei Wang, Gerald Farrell, Yuliya Semenova, Ginu Rajan

Articles

It is shown that manufacturing tolerances of the fiber parameters bend radius and NA significantly influence the fiber bend loss performance and spectral response of a fiber-based edge filter. A theoretical model, validated by experimental results, is used to determine the changes in key spectral parameters for an edge filter, resulting from changes within their manufacturing tolerance range, for both the bend radius and NA. Finally is shown that bend-radius tuning during fabrication of such filters is a means of mitigating the effect of manufacturing variations.

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Single Spin Toffoli-Fredkin Logic Gate, Amit Ranjan Trivedi, S. Bandyopadhyay Jan 2008

Single Spin Toffoli-Fredkin Logic Gate, Amit Ranjan Trivedi, S. Bandyopadhyay

Electrical and Computer Engineering Publications

The Toffoli–Fredkin (TF) gate is a universal reversible logic gate capable of performing logic operations without dissipating energy. Here, we show that a linear array of three quantum dots, each hosting a single electron, can realize the TF gate, if we encode logic bits in the spin polarization of the electrons and allow nearest neighbor exchange coupling. The dynamics of the TF gate is realized by selectively driving spin resonances in the coupled spin system with an acmagnetic field. The conditions for gate operation are established, and an estimate of the switching speed and gate error are provided.

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The Annotation Of Traditional Irish Dance Music Using Matt2 And Tansey, Bryan Duggan, Brendan O'Shea, Mikel Gainza, Padraig Cunningham Jan 2008

The Annotation Of Traditional Irish Dance Music Using Matt2 And Tansey, Bryan Duggan, Brendan O'Shea, Mikel Gainza, Padraig Cunningham

Conference papers

Current estimates put the canon of traditional Irish dance tunes at least 7,000 compositions. Given this diversity, a common problem faced by musicians and ethnomusicologists is identifying tunes from recordings. This is evident even in the number of commercial recordings whose title is gan aimn (without name). This work attempts to solve this problem by developing a Content Based Music Information Retrieval (CBMIR) System adapted to the characteristics of traditional Irish music. A system is presented called MATT2 (Machine Annotation of Traditional Tunes) whose primary goal is to annotate recordings of traditional Irish dance music with useful meta-data including tune …

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Power Amplifier Principles And Modern Design Techniques, Vladimir I. Prodanov, Mihai Banu Jan 2008

Power Amplifier Principles And Modern Design Techniques, Vladimir I. Prodanov, Mihai Banu

Electrical Engineering

No abstract provided.

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Convolutional Coded Generalized Direct Sequence Spread Spectrum, Madan Venn Jan 2008

Convolutional Coded Generalized Direct Sequence Spread Spectrum, Madan Venn

ETD Archive

In this thesis we investigate the worst-case performance of coded ordinary and coded generalized direct sequence spread spectrum (DSSS) systems in a communication channel corrupted by an unknown and arbitrary interfering signal of bounded power. We consider convolutional codes with Viterbi decoding in order to compare the performance of coded ordinary and coded generalized DSSS systems. For the generalized DSSS system, we use a pulse stream of +1,-1 and 0 as the spreading sequence, which is different from ordinary DSSS system which uses the typical sequence with pulse values of +1 and -1. A C program for performing Monte-Carlo simulations …

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