Engineering Commons^™

Automatic Modulation Classification Of Communication Signals, Zaihe Yu

Dissertations

The automatic modulation recognition (AMR) plays an important role in various civilian and military applications. Most of the existing AMR algorithms assume that the input signal is only of analog modulation or is only of digital modulation. In blind environments, however, it is impossible to know in advance if the received communication signal is analogue modulated or digitally modulated. Furthermore, it is noted that the applications of the currently existing AMR algorithms designed for handling both analog and digital communication signals are rather restricted in practice. Motivated by this, an AMR algorithm that is able to discriminate between analog communication …

Fabrication And Characterization Of Back Illuminated Cmos Photodiode Array, Amitra Banerjee

Theses

With the rapid development in low-cost CMOS technology, silicon photodiodes are currently recognized as promising choice for the imager core. In this research, the arrays of back illuminated photodiodes were designed, fabricated and demonstrated with CMOS imager fabrication process on silicon wafers. The main purpose of this work was to improve the contribution of these arrays on the imaging systems before committing their design on the chips.

In this CMOS process, first the n-well, p-well, n+and p+ regions were simulated and fabricated by several implantation processes. The n-well region was implanted by phosphorus at an energy of 170 keV and …

Adaptive Control Of Micro Air Vehicles, Joshua Stephen Matthews

Theses and Dissertations

Although PID controllers work well on Miniature Air Vehicles (MAVs), they require tuning for each MAV. Also, they quickly lose performance in the presence of actuator failures or changes in the MAV dynamics. Adaptive control algorithms that self tune to each MAV and compensate for changes in the MAV during flight are explored. However, because the autopilots on MAVs are small, many of the adaptive control algorithms like those that employ least squares estimation may take too much code space, memory, and/or computing power. In this thesis we develop several Lyapunov-based model reference adaptive control (MRAC) schemes that are both …

Temperature Dependent Analytical Modeling, Simulation And Characterizations Of Hemts In Gallium Nitride Process, Hasina F. Huq

Doctoral Dissertations

Research is being conducted for a high-performance building block for high frequency and high temperature applications that combine lower costs with improved performance and manufacturability. Researchers have focused their attention on new semiconductor materials for use in device technology to address system improvements. Of the contenders, silicon carbide (SiC), gallium nitride (GaN), and diamond are emerging as the front-runners.

GaN-based electronic devices, AlGaN/GaN heterojunction field effect transistors (HFETs), are the leading candidates for achieving ultra-high frequency and high-power amplifiers. Recent advances in device and amplifier performance support this claim. GaN is comparable to the other prominent material options for high-performance …

Design Of An Active Stereo Vision 3d Scene Reconstruction System Based On The Linear Position Sensor Module, Julie Anne Morris

Masters Theses

Active vision systems and passive vision systems currently exist for three-dimensional (3D) scene reconstruction. Active systems use a laser that interacts with the scene. Passive systems implement stereo vision, using two cameras and geometry to reconstruct the scene. Each type of system has advantages and disadvantages in resolution, speed, and scene depth. It may be possible to combine the advantages of both systems as well as new hardware technologies such as position sensitive devices (PSDs) and field programmable gate arrays (FPGAs) to create a real-time, mid-range 3D scene reconstruction system.

Active systems usually reconstruct long-range scenes so that a measurable …

Thermoelectrics For Cooling Power Electronics, Michael Ralf Starke

Masters Theses

To increase the efficiency and reduce emissions, the hybrid electric vehicle (HEV), fuel cell vehicle (FCV), and electric vehicle (EV) types were developed. All these vehicle types rely on power electronics (PEs) to function. Yet, the reliability and performance of PEs are directly related to the operating temperature. Therefore, cooling is considered an option to reduce the operating temperature.

An examination of multiple cooling methods including conventional cooling, direct and indirect cooling, and spray cooling shows that the use of thermoelectric (TE) modules has multiple justifications including reliability, thermal control, operation in harsh conditions, and the non-application of refrigerants. Nevertheless, …

A Low Noise Cmos Charge-Sensitive Preamplifier With Pole/Zero Compensation For A Neutron Detection System, Steven Curtis Bunch

Masters Theses

This thesis presents the design and implementation of a low noise CMOS charge sensitive preamplifier with pole/zero compensation for a neutron detector to be installed on the Spallation Neutron Source in Oak Ridge, TN. The first prototype chip has been fabricated using Taiwan Semiconductor Manufacturing Company (TSMC) 0.35 µm process. The system contains a preamplifier, an active resistive feedback network, a pole/zero compensation network, and the first real pole input to the shaper system. Experimental results of the system show that proper functionality was achieved. The preamplifier is noise dominant with only 540 rms electron noise at 5 pF detector …

Optimization Of The Mod-Viii One Atmosphere Uniform Glow Discharge Plasma Reactor® For Surface Energy Treatment, Truman Andrew Bonds

Masters Theses

A plasma reactor system has been developed to provide roll-to-roll surface treatment of fabrics and films using an air plasma. Effects of air plasma surface treatment at one atmosphere can include etching, cleaning, sterilization, disinfection, and increasing surface energy, all without the use of chemical inputs and with minimal toxic by-products. Webs can be continuously and uniformly treated by proper control of gas flow, electrode configuration, plasma parameters, fabric speed, and fabric tension. Tests conducted in this work focused on raising the surface energy of PET and HDPE using various electrode configurations. For industrial applications, the exposure time required to …

Vector Control And Experimental Evaluation Of Permanent Magnet Synchronous Motors For Hevs, Timothy Adam Burress

Masters Theses

The 2004 Toyota Prius exceeded sales expectations and led the automotive industry to realize that there is a healthy market for hybrid electric vehicles (HEVs). The Prius uses two interior permanent magnet motors to manipulate power flow throughout the drive system. Permanent magnet synchronous motors (PMSMs) are most suitable for HEVs and full electric vehicles due to their high efficiency, high power density, and fast dynamic response. This thesis will present vector control theory for PMSMs, with focus on interior permanent magnet motors.

The primary 50kW drive motor and inverter of the 2004 Toyota Prius Synergy drive system was removed …

A Class-E Inductive Powering Link With Backward Data Communications For Implantable Sensor Systems, Mohammad Ahsanul Adeeb

Masters Theses

The design and implementation of a wireless power and data transfer system based on inductive coupling, having the potential to be used in numerous implantable bio-medical sensors and systems, is presented. The system consists of an external (primary) unit and an internal (secondary) unit. The external unit incorporates a high-efficiency switch-mode Class-E amplifier operating at ~200 kHz for driving the primary coil. The secondary unit consists of a parallel resonant coil followed by the power recovery circuitry. Means for backward data communication from the internal to the external unit over the same pair of coils has been realized using a …

System-On-Chip Design And Test With Embedded Debug Capabilities, Tushti Marwah

Masters Theses

In this project, I started with a System-on-Chip platform with embedded test structures. The baseline platform consisted of a Leon2 CPU, AMBA on-chip bus, and an Advanced Encryption Standard decryption module. The basic objective of this thesis was to use the embedded reconfigurable logic blocks for post-silicon debug and verification.

The System-on-Chip platform was designed at the register transistor level and implemented in a 180-nm IBM process. Test logic instrumentation was done with DAFCA (Design Automation for Flexible Chip Architecture) Inc. pre-silicon tools. The design was then synthesized using the Synopsys Design Compiler and placed and routed using Cadence SOC …

Migration From Teleoperation To Autonomy Via Modular Sensor And Mobility Bricks, Roselyne Dalanda Barreto

Masters Theses

In this thesis, the teleoperated communications of a Remotec ANDROS robot have been reverse engineered. This research has used the information acquired through the reverse engineering process to enhance the teleoperation and add intelligence to the initially automated robot. The main contribution of this thesis is the implementation of the mobility brick paradigm, which enables autonomous operations, using the commercial teleoperated ANDROS platform. The brick paradigm is a generalized architecture for a modular approach to robotics. This architecture and the contribution of this thesis are a paradigm shift from the proprietary commercial models that exist today. The modular system of …

Simulation Of Power System Response To Reactive Power Compensation, Pierre Alexander Boheme

Masters Theses

The demand of power in theUnited Stateshas doubled in the last decade. The constant increase in power flow has saturated the existing infrastructure. Modern advances in technology are changing the way utility industry increases the transmission of power throughout the country. Distributed Energy Resources are constantly improving their reliability and power capabilities.

This thesis will simulate the response of the power system to reactive power injection. The testing will take place in the Reactive Power Laboratory at Oak Ridge National Laboratory. The facility is an initiative by the U.S. Department of Energy to facilitate the development of new resource technologies. …

Automated Design Space Exploration For Digital Hardware, Jonathan Logan Turnmire

Masters Theses

Hardware design in VHDL can be a tedious and daunting task. One of the final steps is to realize the design in hardware. Whether targeting a field programmable gate array (FPGA) or an application specific integrated circuit (ASIC), some time needs to be spent optimizing the design to meet project requirements. This paper details the use of the Synplicity physical synthesis toolsets for FPGAs on the UT Solaris workstation cluster, evaluation of the Synplicity physical synthesis toolsets to determine their efficacy in achieving multiple solutions over the power-delay-area design space and evaluation of the Liberator toolset for ASIC design to …

Mitigation Of Window Effects In Inverse Synthetic Aperture Radar (Isar) Imagery Using Multi-Resolution Technique, Suman Kumar Gunnala

Electrical Engineering Theses

A method using Multi-Resolution technique for window effect mitigation in ISAR imagery, which occurs due to finite extent data, is presented in this work. Proposed method is supported with quantitative measure using both Structural Similarity (SSIM) and Mean Square Error (MSE). In addition, above index measures were used to determine the best choice of wavelet basis for window effect mitigation. Complete angular window and partial angular window are used as two cases to demonstrate the validation of above contributions. Scattering measurements of different test sets were done to validate the approach. Results which include reconstructed images and quantitative index measures …

Modeling And Performance Evaluation Of A Power Electronic-Based Controlled Fuel Cell System, Yashar Ehsan Kenarangui

Electrical Engineering Theses

In fuel cell applications, design of an appropriate controller and selection of an Ultra-Capacitor require a suitable model of fuel-cell-systems that can adequately represent the significant characteristics of the system. Such a model, using lumped circuit elements, was developed in this thesis via a simple method without requiring fuel cell design parameters. To validate the model, simulation results from the model were compared against the results from experimental setups and satisfactory results were obtained. Later, this model was used in order to design a controller that meets the control objectives, namely, regulation of output voltage and attenuation of load current …

Electromagnetic Wave Scattering From Vegetation, Xiaoyan Huang

Electrical Engineering Dissertations

This dissertation contains the theoretical study of microwave scattering from vegetated media and the development of microwave scattering models with applications to these media. A vegetation canopy may consist of deciduous or coniferous leaves, branches, and trunks with certain size and orientation distributions. The formulation of the scattering model for each element of the canopy is carried out and its scatter patterns versus its size and orientation for like and cross polarizations are computed and presented. In particular, an extension is made where vegetation with a compound-leaf pattern is considered. For this type of vegetation, several leaves that form a …

Optimization Of Hydrogen Filling Station, Vishal Bhan

Electrical Engineering Theses

After experiencing the price hikes in the fuel and electricity, renewable energy is considered as one of the most attractive alternatives for future utility industry. Also, Hydrogen via renewable energy is of interest due to the environmental concern when compared with traditional fossil fuels. The Energy Bill of 2005 has included an authorization of $3.7 billion for hydrogen and fuel cell research and development. Further, hydrogen fuel cell vehicles (FCVs) are currently in the pre-production stage of development and the infrastructure needs to support them. Hence to overcome issues like price hike, exhaustion of crude oil and to gain appreciation …

Device Level Vacuum Packaged Microbolometers On Flexible Substrates, Aamer Mahmood

Electrical Engineering Dissertations

Micromachined microbolometers on flexible substrate have been fabricated and characterized. Liquid polyimide PI5878G made by HD Microsystems has been used to form the flexible substrate. Semiconducting Yttrium-Barium-Copper-Oxide (commonly referred to as YBCO) is the temperature sensitive material. These detectors are supported by thin micromachined layers of silicon nitride on flexible polyimide PI5878G. The devices were characterized for temperature dependent resistance (R(T)), the temperature coefficient of resistance (TCR, ), responsivity , detectivity (D*) and thermal conductance (Gth). A typical device had a resistance of 3.76 MI and a TCR of -2.63 %/K at 301 K. The measured thermal conductance was W/K. …

The Design And Analysis Of Optical Scanners For Optical Coherence Tomography, Naresh Dhaubanjar

Electrical Engineering Theses

A miniature fiber optic scanner capable of two-dimensional scanning for medical imaging is designed and developed. The scanner is actuated externally using an electromagnet. Nickel gel, a soft ferromagnetic material, is coated on the optical fiber. The performance of the scanner is characterized. Finite element analysis is performed to validate the theoretical and experimental results. A design and analysis of a cantilever type electrostatic zipping actuator and a bidirectional vertical thermal actuator are presented. The actuation principle, lumped modeling analysis, experimental results, and finite element analysis of both actuators are presented. The actuators are characterized statically and dynamically using the …

Emulation Of Asic Based Network Processor On A Fpga Platform, Sharada Vajja

Electrical Engineering Theses

ABSTRACT Exponential increase of device sizes and complexity of ASICs mandate the need for design verification to meet timing specifications and functionality requirements. Verification techniques are broadly implemented in three categories viz., simulation, verification using commercial emulators and FPGA based prototyping. An Intel architecture based network processor, to be taped out in the near future, is being emulated on FPGA based platform. The basic blocks of the Network Processor, for instance, the Memory Controller Hub and I/O controller Hub were synthesized to be configured on FPGAs. The work involved synthesizing the design, partitioning it on multiple FPGAs and pin multiplexing …

Recirculating Loop Testbed For All Optical 2r Regeneration, Pallavi Govind Patki

Electrical Engineering Theses

This Master's thesis deals with building a recirculating loop testbed intended for proof-of-principle demonstration of multichannel all-optical 2R regenerator proposed in [1]. The proposed multichannel 2R regeneration scheme uses multiple highly-nonlinear-fiber (HNLF) sections separated by dispersion-compensating periodic-group-delay devices (PGDDs). The high cost and limited availability of these devices restrict us to working with just one PGDD, instead of 16 required by the scheme. Thus, for the proof-of-principle demonstration of the regenerator we have to put a single PGDD and a piece of HNLF into a recirculating loop through which light will circulate for required number of times. In this thesis, …

3d Interconnects For Die And Wafer Stacks, Rachita Dewan

Electrical Engineering Theses

3D integration results from the ever demanding trend towards smaller and lower-profile, lighter and lower cost packaged devices requires further package miniaturization. With the present System-on-chip (SOC) technology reaching its limitation in terms of functionality and cost, effort are being concentrated on exploring the third dimension, i.e. 3D integration. It provides a volumetric packaging solution for higher integration and performance and results in size and weight reduction. Approaches to achieve 3D integration are die and wafer stacking. A key technology to realize the potential of stacking is implementation of vertical electrical interconnects between die and wafer stacks. This thesis discusses …

Nonlinear Control Of Microelectromechanical Systems (Mems) Devices, Kwadwo Osei Owusu

Electrical Engineering Theses

Different actuation principles have been developed for MEMS but electrostatic actuators are the most common. A significant drawback in the use of electrostatic actuators for some applications is their nonlinear voltage to position characteristics. Analog operation of these devices requires the use of feedback to stabilize and linearize them. Controlling and optimizing the operation of electrostatic controllers using feedback requires the establishment of the complete and accurate dynamical model of the device. In this thesis, we show how an optical switch driven by a MEMS electrostatic comb drive is controlled to guarantee its performance, stability and reliability for use in …

Hourly Weather Forecast Analysis, Sothaya Rasmidatta

Electrical Engineering Theses

Today, internet becomes one of the most important resources for useful information. However, since the authentic of the information is difficult to verify, one also has to take precaution when getting information from the internet. Utility companies need to forecast their load for unit commitment scheduling and system planning. The traditional approach for neural network forecasting relies on the temperature forecasting information from a single source. The customer loads are closely correlated with the temperature. Therefore, the accuracy of the load forecasting is affected by the temperature forecasting errors. The objective of this thesis is to reduce the temperature forecasting …

Rf Mems And Integrated Manufacturing For Miniaturized Millimeter-Wave Systems, Ying Cai

Electrical Engineering Dissertations

Recently millimeter-wave systems have attracted more attentions in applications owing to their short wavelengths, high resolutions, broad bandwidths and high environmental tolerance. However, the great challenges of high fabrication and assembly costs, bulky volume, and heavy weight of millimeter-wave systems call for new integrated manufacturing techniques and novel architectures. The micro hot embossing technique integrated with other microfabrication techniques could address these challenges. In this dissertation, the micro plastic hot embossing technique was presented for the fabrication of miniaturized millimeter-wave systems. The micro hot embossing on plastic materials demonstrated its advantages on significant costs, volume, and weight reduction, while maintaining …

Video Stabilization And Target Localization Using Feature Tracking With Video From Small Uavs, David Linn Johansen

Theses and Dissertations

Unmanned Aerial Vehicles (UAVs) equipped with lightweight, inexpensive cameras have grown in popularity by enabling new uses of UAV technology. However, the video retrieved from small UAVs is often unwatchable due to high frequency jitter. Beginning with an investigation of previous stabilization work, this thesis discusses the challenges of stabilizing UAV based video. It then presents a software based computer vision framework and discusses its use to develop a real-time stabilization solution. A novel approach of estimating intended video motion is then presented. Next, the thesis proceeds to extend previous target localization work by allowing the operator to easily identify …

Mid-Infrared Multiple Quantum Well Lasers Using Digitally-Grown Allnassb Barriers And Strained Inassb Wells, Leslie G. Vaughn

Electrical and Computer Engineering ETDs

Al_xln_(1-x)As_ySb_(1-y)quaternary alloys have been used in Type I midwave infrared (MWIR) laser structures as barrier materials with lnAs and InAsSb quantum wells. However, growth of these alJoys has limited the application because of a large miscibi lity gap. In this research, quaternary films with compositions well into the miscibility gap (0

Combining the quaternary bandgap equation with strain and quantum size effects. the wavelengths for strained lnAsSb wells in AllnAsSb quaternary barriers are predicted and compared to measured values generated from PL experiments. The reasonable agreement of these experimental results with the …

Melt Detection And Estimation In Greenland Using Tandem Quikscat And Seawinds Scatterometers, Brandon R. Hicks

Theses and Dissertations

Ku-band dual-polarization radar backscatter measurements from the SeaWinds on QuikScat (QuikScat) and SeaWinds on ADEOS-2 (SeaWinds) scatterometers are used to classify the melt state and estimate melt severity in Greenland. Backscatter measurements are organized into high temporal and high spatial resolution images created using the Scatterometer Image Reconstruction (SIR) algorithm and a new temporal data segmentation technique. Melt detection is performed using a layered electromagnetic model combined with a Markov chain model. The new melt detection method allows classification of the snow-pack into three states: melt, refreeze, and frozen. Melt severity and refreeze severity indexes are also developed. The melt …

Microwave Remote Sensing Of Saharan Ergs And Amazon Vegetation, Haroon Stephen

Theses and Dissertations

This dissertation focuses on relating spaceborne microwave data to the geophysical characteristics of the Sahara desert and the Amazon vegetation. Radar and radiometric responses of the Saharan ergs are related to geophysical properties of sand formations and near surface winds. The spatial and temporal variability of the Amazon vegetation is studied using multi-frequency and multi-polarization data. The Sahara desert includes large expanses of sand dunes called ergs that are constantly reshaped by prevailing winds. Radar backscatter measurements observed at various incidence and azimuth angles from the NASA Scatterometer (NSCAT), the ERS scatterometer (ESCAT), the SeaWinds scatterometer aboard QuikScat (QSCAT), and …