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Pyles, David T.Effects of the Kinematic Model on Forward-Model Based Spotlight SAR ECM
Master of Science in Electrical Engineering (MSEE), Wright State University, 2017, Electrical Engineering
Spotlight synthetic aperture radar (SAR) provides a high-resolution remote image formation capability for airborne platforms. SAR image formation processes exploit the amplitude, time, and frequency shifts that occur in the transmitted waveform due to electromagnetic propagation and scattering. These shifts are predictable through the SAR forward model which is dependent on the waveform parameters and emitter flight path. The approach to develop an electronic countermeasure (ECM) system that is founded on the SAR forward model implies that the ECM system should alter the radar’s waveform in a manner that produces the same amplitude, time, and frequency shifts that a real scatterer would produce at a desired location. A collection of such scatterers would be capable of forming a larger collective energy distribution in the final image. However, since the forward model is dependent on the radar platform’s kinematic model, the jamming energy distribution created from a forward-model based ECM system will inherently have some level of sensitivity to kinematic error. This thesis discusses a forward-model based ECM modulation scheme and provides an assessment of its sensitivity through Monte Carlo simulations and an entropy-based image similarity distance.

Committee:

Michael A. Saville, Ph.D. (Committee Chair); Brian Rigling, Ph.D. (Committee Member); Steve Gorman, Ph.D. (Committee Member)

Subjects:

Electrical Engineering

Keywords:

electrical engineering; spotlight synthetic aperture radar; SAR

Chunchu, Vinay KumarLayout Implementation of A 10-Bit 1.2 GS/s Digital-to-Analog Converter In 90nm CMOS
Master of Science in Electrical Engineering (MSEE), Wright State University, 2017, Electrical Engineering
Digital-to-analog converters are the interface circuits between digital and analog domains. They are used in data communication applications and different sorts of applications where transformation amongst digital and analog signals is needed. High-speed data converters are needed to match the bandwidth demands of the present-day communication systems. This thesis presents the layout implementation of a 10-bit current steering DAC with a sampling rate of about 1.2 GS/s using CMOS 90 nm technology. Current steering DAC topology is used in high-speed applications. The DAC in this thesis is designed using a segmented architecture in which 4 LSB current cells are binary weighted and 6 MSB current cells are thermometer encoded. The issues with the mixed signal layout were discussed. The schematic design does not consider the effect of parasitic resistance and capacitance whereas the layout does. The performance of the schematic and layout designs of the sub-circuits was compared. Post layout simulations of the implemented current steering DAC were performed in Cadence with 1.2 GHz clock and 55.07 MHz input signal. The simulations show that the DAC is functional and comparisons between the layout and schematic were presented.

Committee:

Saiyu Ren, Ph.D. (Advisor); Raymond E. Siferd, Ph.D. (Committee Member); Marian K. Kazimierczuk, Ph.D. (Committee Member); Yan Zhuang, Ph.D. (Committee Member)

Subjects:

Electrical Engineering

Keywords:

electrical engineering

Avanesian, DavidHARDWARE IMPLEMENTATION OF ACTIVE DISTURBANCE REJECTION CONTROL FOR VIBRATING BEAM GYROSCOPE
Master of Science in Electrical Engineering, Cleveland State University, 2007, Fenn College of Engineering
Obtaining the approximation of rotation rate form a Z-Axis MEMS gyroscope is a challenging problem. Currently, most commercially available MEMS gyroscopes are operating in an open-loop for purposes of simplicity and cost reduction. However, MEMS gyroscopes are still fairly expensive and are not robust during operation. The purpose of this research was to develop a high-performance and low-cost MEMS gyroscope using analog Active Disturbance Rejection Control (ADRC) system. By designing and implementing analog ADRC both above requirements were satisfied. Analog ADRC provides the fastest response time possible (because the circuit is analog), eliminates both internal and external disturbances, and increases the bandwidth of the gyroscope beyond its natural frequency. On the other hand, the overall design is extremely economical, given that the system is built using pure active and passive analog components. This work, besides achieving high-performance and providing low-cost solution, furnishes two novel designs concepts. First, Active Disturbance Rejection Controller can now be build using pure analog circuit, which has never been done before. Second, it is the first time that the advanced controller has been successfully implemented in hardware to control an inertial rate sensor like gyroscope. This work provides a novel solution to applications that require high-performance and low-cost inertial sensors.

Committee:

Lili Dong (Advisor)

Keywords:

Electrical Engineering; Gyroscope

Namala, PraneethA 13T Single-Ended Low Power SRAM Using Schmitt-Trigger and Write-Assist
Master of Science in Electrical Engineering (MSEE), Wright State University, 2017, Electrical Engineering
SRAMs are widely used in application based systems like medical instruments, portable electronic devices from caches to registers. Technology scaling of transistor into nanometer regime has substantially increased memory density that occupies large silicon area in today’s IC’s and consumes significant amount of active and leakage power. So, design requirements and challenges such as memory write and read speed, leakage power, noise margin and process-voltage-temperature (PVT) variations also significantly increase. In this thesis, a 13T single-ended low power SRAM using Schmitt-Trigger and write-assist technique is presented. It enhances read static noise margin, write-1 and read-0 access time, specifically at low supply voltages. Designed in 1.05V 32 nanometer CMOS process, employing a Schmitt-Trigger in SRAM design achieves a higher read static noise margin (RSNM) of 3.65x and 1.79x as that of the standard 6T and conventional 8T SRAM, respectively. The read port configuration used in this SRAM design reduces about 50% of the Read-Bit-Line (RBL) leakage from un-accessed memory cells as compared with conventional 8T SRAM. The SRAM functions successfully with a minimum VDD of 340 mV, 100 mV lower than the threshold voltage so as to consume extremely low power.

Committee:

Chien-In Henry Chen, Ph.D. (Advisor); Yan Zhuang, Ph.D. (Committee Member); Jiafeng Xie, Ph.D. (Committee Member)

Subjects:

Electrical Engineering

Keywords:

electrical engineering

Kotti, VivekDesign of an 8-bit Successive Approximation Pipelined Analog to Digital Converter (SAP-ADC) in 90 nm CMOS
Master of Science in Electrical Engineering (MSEE), Wright State University, 2017, Electrical Engineering
Analog to Digital Converters bridge the gap between physical world and digital signal processing. Most times analog signals received from the real world needs to be amplified and converted to digital to impart various signal enhancements to the received signal. The digital signal is much suitable to operate on with less noise and well defined logic levels when compared to continuously varying analog signal. Communication systems demand ever-increasing bandwidth which unfortunately has been a huge limitation for present day ADCs. Hence, an architecture which combines the accuracy of a SAR -ADC with the concept of pipelining to increase the bandwidth can be a great solution to achieve high sampling frequency (GHz) and broad bandwidth. The 8- bit SAP ADC implemented in this thesis using 90nm COMS technology achieves a sampling rate of 1GHz with input frequencies up to 125MHz

Committee:

Saiyu Ren, Ph.D. (Advisor); Raymond Siferd, Ph.D. (Committee Member); Marian Kazimierczk, Ph.D. (Committee Member)

Subjects:

Electrical Engineering

Keywords:

electrical engineering

Groves, Brenton RobertThe use of computer-generated motion pictures in the analysis of electrical engineering phenomena /
Doctor of Philosophy, The Ohio State University, 1966, Graduate School

Committee:

Not Provided (Other)

Subjects:

Engineering

Keywords:

Computer graphics;Electronic data processing;Electrical engineering

Zemba, Michael JSite Characterization of Phase Instability via Interferometer Measurement
Master of Science in Engineering, University of Akron, 2013, Electrical Engineering
Single-dish reflector antennas are often used for their ability to produce a highly directive (narrow beam) radiation pattern which increases in directivity as the diameter of the reflector increases. However, as reflectors grow larger in the pursuit of more directivity, they become more expensive and unwieldy to construct, maintain, and operate. A more practical solution is to employ an array of elements which are smaller individually, but which can yield similar or better gains when arrayed together. However, one trade-off associated with this approach is that antenna arrays are subject to losses introduced by atmospheric turbulence. Inhomogeneous cells of water vapor in the troposphere change the refractivity of the air along the path of the propagating wave, distorting the wavefront and introducing a phase error between the elements of the array. These losses are stochastic and site-dependent. Techniques have been developed over the past several decades to compensate for such losses on the receiving end, but uplink arraying remains challenging as it requires prediction of atmospheric conditions to effectively compensate the signal before transmitting. This is especially true at higher frequencies such as Ka-band given that atmospheric phase noise increases with frequency. Thus, a critical first step in system planning is to determine the losses a particular array configuration will experience based on the phase statistics of a given site. To this end, NASA Glenn Research Center has deployed site test interferometers to three ground-station sites with the intent to characterize their phase instability ahead of upgrades to Ka-Band operation. The sites to be studied are Goldstone, California; White Sands, New Mexico; and the island of Guam. Using three years of data collected from these campaigns, the primary goal of this thesis is to develop a thorough characterization of the phase statistics of each site which may then be used to determine the sites’ suitability for uplink arraying. In addition, a secondary goal is the development of the data analysis software suite that was used to process the data, which it is hoped will facilitate easy analysis of future sites for system designers.

Committee:

Nathan Ida, Dr. (Advisor); Igor Tsukerman, Dr. (Committee Member); Subramaniya Hariharan, Dr. (Committee Member)

Subjects:

Aerospace Engineering; Electrical Engineering; Electromagnetics; Electromagnetism; Engineering

Keywords:

Antenna Arrays; Phase Noise; Atmospheric Phase Instability; Propagation Measurements; Interferometry; NASA; Ka-Band; Radio Frequency; Electrical Engineering; Electromagnetics; Antennas; Propagation; Site Test Interferometer

Kolker, Rachael E.GNSS Receiver Testing and Algorithm Development
Master of Science in Electrical Engineering (MSEE), Wright State University, 2017, Electrical Engineering
Many current GNSS Software Defined Receivers (SDRs) are often limited in what they can do across a range of developmental applications. They cannot perform acquisition and tracking without several iterations of coding, which does not allow for fast processing. This work provides a Matlab SDR that is based on freely available and optimized components that can be applied to all GNSS signals. A previous basis has been expanded upon to perform tracking of QZSS signals. In addition to this, two separate hardware front ends were compared and their differences analyzed. These hardware systems collected data with different disciplining clocks, but there was no evidence to show that a significant difference occurred depending on the clock type.

Committee:

Brian Rigling, Ph.D. (Advisor); John Macdonald, Ph.D. (Committee Member); Arnab Shaw, Ph.D. (Committee Member)

Subjects:

Electrical Engineering

Keywords:

electrical engineering

Chen, JianRF CMOS Band Pass Filters with Wide Tuning Frequency, Controllable Pass Band and High Stopband Rejection: Using Passive and Active Inductors
Doctor of Philosophy (PhD), Wright State University, 2016, Engineering PhD
With the increasing demand for high performance RF front-end modules, like multimedia handset and base station devices accommodating multiple wireless standards (2G, 2.5G, 3G, WiMAX, and LTE). Multiple IF amplifiers, mixers, RF band pass filters (BPFs), modulators and demodulators are desired to be tunable to meet dynamic standards with different frequency bands. Tunable devices with wide tuning frequency range, tuning speed, high linearity, energy conservative, high pass band gain, high stop band rejection are the paramount components in the reconfigurable RF front-end systems. In this dissertation, first a wide tuning passive inductor band pass filter (BPF) with steep roll-off high rejection and low noise figure is presented. The design feature of steep roll-off high stopband rejection (> 20 dB) and low noise figure (< 6 dB) provides a wide tuning frequency span (1-2.04 GHz) to accept desirable signals and reject close interfering signals. Next, a process variation aware design approach is proposed to verify robustness of the BPF after calibration from process variations. By operating in 1.04 GHz tuning frequency span the BPF achieves a stable center frequency, an average maximum deviation 1.16 dB on a nominal pass band gain of 55.6 dB, and an average maximum deviation 1.06 MHz on a nominal bandwidth of 12.3 MHz. Next, a high inductance high Q factor floating CMOS RF active inductor (AI) is proposed, which uses a resistive feedback and a negative resistance block. By changing design parameters, an active inductor designed in 1.8 V 180 nanometer CMOS process achieves a tuning inductance range from 52 nH to 1,462 nH at 1.52 GHz and a maximum Q factor of 553k at 1.27 GHz. Its wide tunable frequency span can be increased to 3.09 GHz. Its power is below 7.59 mW. Next, a AI driven BPF is proposed, which increases the BPF tuning frequency span from the original 1.04 GHz (1.0 - 2.04 GHz) to 2.1 GHz (1.0 - 3.1 GHz) while keeps a pass band gain (21.1 ~ 28.2 dB). The AI driven BPF achieves a low noise figure (1.81~5.42 dB), a power consumption of 18.6 mW, and a high stopband rejection of 28.9 dB. The AI driven BPF tuning frequency span can be further increased to 7.74 GHz (0.39 - 8.13 GHz) with a pass band gain of 8.14 dB. Finally, a wide tuning inductorless BPF is proposed. The BPF has two tuning frequency spans: 1) a tuning frequency span of 1.33 GHz (0.74 - 2.07 GHz) while keeping a pass band gain (2.17 - 17.04 dB), a low noise figure (6.3 - 10.2 dB), and a power of 22.6 mW, and 2) a tuning frequency span of 1.26 GHz (1.15 - 2.41 GHz) while keeping a pass band gain (4.83 - 19.7 dB), a low noise figure (7.12 to 12.5 dB), and a power of 23.4 mW.

Committee:

Chien-In Henry Chen, Ph.D. (Advisor); Marian Kazimierczuk, Ph.D. (Committee Member); Jack Jean, Ph.D. (Committee Member); Yang Zhuang, Ph.D. (Committee Member); Wen-Ben Jones, Ph.D. (Committee Member)

Subjects:

Electrical Engineering

Keywords:

electrical engineering

Thurston, Marlin OakesA self-excited frequency multiplier for the millimeter wave-length range
Doctor of Philosophy, The Ohio State University, 1955, Electrical and Computer Engineering
N/A

Committee:

E. Milton Boone (Advisor)

Subjects:

Electrical Engineering

Keywords:

Electrical Engineering

Gaerke, Tiffani MCharacteristic Functions and Bernoulli-Gaussian Impulsive Noise Channels
Master of Science, University of Akron, 2014, Mathematics
In this thesis, we attempt to find the necessary and sufficient conditions on the input distribution of a Bernoulli-Gaussian impulsive noise channel in order to obtain an optimal Gaussian output, maximizing the entropy capacity of the channel. We will briefly discuss the capacity of such a channel, assuming that an optimal input is available. We will derive a function which must be the characteristic function of the optimal input X if such an input exists. We then begin to validate the characteristic function. To do so, we will examine some of the necessary and sufficient conditions for determining whether a given function is a characteristic function. In particular, we give a rigorous proof that a radial function is a characteristic function of some random variable if and only if it is a completely monotone function. We then employ the property of complete monotonicity to establish a concrete necessary and sufficient condition for obtaining the optimal Gaussian output. Using this, we also identify some cases when the Bernoulli-Gaussian impulsive noise channel never has the Gaussian distribution as an output.

Committee:

Truyen Nguyen, Dr. (Advisor); Dmitry Golovaty, Dr. (Committee Member); J. Patrick Wilber, Dr. (Committee Member)

Subjects:

Electrical Engineering; Mathematics; Statistics

Keywords:

Characteristic function; criterion of characteristic functions; electrical engineering;

Lawyer, Cody A.Impact of SAR Image Formation Quality on Target Separability
Master of Science in Engineering (MSEgr), Wright State University, 2014, Electrical Engineering
The polar format algorithm (PFA) allows the use of computationally efficient fast Fourier transforms in synthetic aperture radar (SAR) image formation, but introduces phase errors when making the far-field approximations that facilitate this approach. The phase errors cause spatially variant distortion and defocus in the formed image. These effects may complicate target recognition applications. To limit the impact of defocus, scene size is usually limited such that the maximum quadratic phase error within an image falls below some threshold. This thesis looks at how distortion and defocus affects the classification of targets, with the hope of developing an application-driven scene size limit.

Committee:

Brian Rigling, Ph.D. (Advisor); Fred Garber, Ph.D. (Committee Member); Michael Saville, Ph.D. (Committee Member)

Subjects:

Electrical Engineering

Keywords:

electrical engineering

Chen, HuiDistributed Sensor Fault Diagnosis for Automated Highway Systems
Master of Science in Engineering (MSEgr), Wright State University, 2013, Electrical Engineering
Fault diagnosis problems for large-scale nonlinear systems have attracted significant attentions from researchers in recent years. Most fault detection and isolation (FDI) methods have been proposed based on a centralized architecture. However, due to the complexity of the system, most of these centralized fault detection and diagnosis schemes are not able to delivery effective fault detection and isolation performance for a large-scale nonlinear system, which contains subsystems interacting with neighboring subsystems. In this thesis, a distributed fault detection and isolation method is developed for the automated highway systems (AHS). For each subsystem of AHS, a distributed fault detection and isolation component is designed to detect and isolate a sensor fault in the system. Each component uses the local measurements and communicated information from other neighboring fault detection and isolation components. In each local subsystem of AHS, adaptive thresholds for fault detection and isolation are derived based on the distributed fault diagnosis decision scheme. Simulation results for two case studies show the effectiveness of the distributed FDI method.

Committee:

Xiaodong Zhang, Ph.D. (Advisor); Kefu Xue, Ph.D. (Committee Member); Zhiqiang Wu, Ph.D. (Committee Member)

Subjects:

Electrical Engineering

Keywords:

electrical engineering

Li, DongMixed Signal Detection and Parameter Estimation based on Second-Order Cyclostationary Features
Master of Science in Engineering (MSEgr), Wright State University, 2015, Electrical Engineering
Signal detection and radio frequency (RF) parameter estimation have received a lot of attention in recent years due to the need of spectrum sensing in many military and civilian communication applications. In most of existing work, the target signal is assumed to be a single RF signal with no overlapping with other RF signals. However, in a spectrally congested and spectrally contested environment, multiple signals are often mixed together at the signal detector with significant overlap in spectrum. Conventional frequency analysis through Fourier transform is not capable of detecting mixed signals with significant spectral overlap. In this thesis, we first demonstrate the feasibility of using second-order cyclostationary feature to perform mixed signal detection. We then use the cyclostationary features to estimate the carrier frequencies of these mixed signals. Next, we extend our work to higher order modulation. We develop a robust algorithm to detect mixed signals and estimate their symbol rates as well as carrier frequencies via spectral coherence function (SOF) features. Furthermore, we evaluate the detection and estimation performances of the proposed algorithm in various channel conditions and signal mixture scenarios. Simulation results confirm the effectiveness of the proposed schemes.

Committee:

Zhiqiang Wu, Ph.D. (Advisor); Kefu Xue, Ph.D. (Committee Member); Yan Zhuang, Ph.D. (Committee Member)

Subjects:

Electrical Engineering

Keywords:

electrical engineering

Zhang, XiaomengMulti-finger MOSFET Low Noise Amplifier Performance Analysis
Master of Science in Engineering (MSEgr), Wright State University, 2014, Electrical Engineering
Multi-finger layout technique has been extensively used in Nano-scale CMOS circuit design due to the increased circuit performance compared to a single finger layout. However choosing a finger width (W_f) and number of fingers (N_f) to optimize circuit performance is a challenging problem. In this thesis, the performances of 2.4GHz and 6.0GHz single ended low noise amplifiers (LNA) with fixed total transistor widths in 90nm CMOS technology are analyzed as function of number of fingers, bias voltage (V_bias) and channel length (L). The results show that the drain to source current, transconductance and effective gate capacitance increase with increasing number of fingers. The effect of finger numbers, supply voltage and channel length on transistor cutoff frequency, low noise amplifier noise figure, voltage gain, center frequency, and impedance matching is presented. The simulation results show that the finger numbers affect the single ended cascode low noise amplifier slightly due to the inductors used. The bias voltage and channel length are the key parameters for this low noise amplifier design. A 200nm transistor length LNA has better gain and filter quality factor compared with 100nm for 2.4GHz and 6GHz cases in 90nm process. A higher bias voltage can decrease the noise figure, however, the trade-off is the power consumption is increased.

Committee:

Saiyu Ren, Ph.D. (Advisor); Raymond Siferd, Ph.D. (Committee Member); Yan Zhuang, Ph.D. (Committee Member)

Subjects:

Electrical Engineering

Keywords:

electrical engineering

Hunt, Victor J.Nondestructive Evaluation and Health Monitoring of Highway Bridges
PhD, University of Cincinnati, 2000, Engineering : Electrical Engineering
This research seeks the rational organization and integration of nondestructive evaluation (NDE) technologies, the methods of structural identification, and concepts of reliability and fault detection, each according to its merits, within a system devoted to monitoring the state-of-health of an instrumented structure. A global NDE methodology has been developed based upon the structural identification concept, employing truckload testing, modal testing, and instrumented monitoring as its principal experimental tools. The test results are transformed to both strain influence lines and modal flexibility, which have been demonstrated to be a conceptual, quantitative, comprehensive, and damage-sensitive signature. These parameters also provide an accurate condition index, since it may be used to conveniently obtain the stress profiles and deflected shapes of a bridge under any loading pattern. The capacity rating for the instrumented section and/or an estimation of the remaining fatigue life for the instrumented member/connection based upon the relevant AASHTO codes can be obtained immediately following the controlled truckload testing of the bridge. This methodology has provided several unique deliverables to the aforementioned field of expertise: 1. The application, verification, and assessment of truckload testing, modal impact testing, and long-term monitoring procedures, as well as their necessary sensor types and positioning, for several highway bridges. 2. A reduced set of quantitative models for the estimation and identification of single and multiple span beam response to truckload and impact in both the time and frequency domains. 3. The quantitative evaluation of the most promising damage indices for the detection of induced damage-types on a decommissioned specimen. 4. The quantitative identification of AASHTO condition indices and their requisite assumptions from the acquired field data. The most important contribution of this research is an objective technique for the accurate field identification of bridge parameters (specifically, strain influence lines and modal flexibility) which not only provide for the timely assessment of structural condition but are also sensitive to typical damage scenarios. These results are achieved without a finite element model, but can also serve to calibrate such a model for greater spatial precision and the investigation of other possible damage scenarios, repair/retrofit schemes, and other structural considerations.

Committee:

Arthur Helmicki, PhD. (Advisor)

Keywords:

electrical engineering; civil engineering; system science

Danekar, Abhishek V.Analysis and Design of High-Frequency Soft-Switching DC-DC Converter for Wireless Power Charging Applications
Master of Science in Electrical Engineering (MSEE), Wright State University, 2017, Electrical Engineering
Wireless power transfer (WPT) technology is becoming attractive in a wide variety of applications such as electric-vehicle charging, induction heating, charging portable applications, industrial robots, and biomedical implants. Recent studies have shown various techniques to implement wireless power transfer and these techniques differ based on the type of applications. For example, for electric vehicle charging, the power levels are in the range 5 kW to 25 kW and the operating frequency is in the range 70 kHz to 110 kHz. On the other hand, for consumer applications, the power levels vary from a few watts to hundreds of watts and operates at frequencies of the order of 5 MHz to 10 MHz. This thesis addresses the analysis, design, implementation, and simulation of a wireless charging system targeted towards a high-frequency, low-power portable application with wide separation between transmitter and receiver. The WPT system is composed of three important blocks: inverter (or transmitter), transformer (or coil), and rectifier (or receiver). Hard-switching inverters and rectifiers have major drawbacks at high frequencies due to large switching power loss. Therefore, soft-switching Class-E topology is chosen. The Class-E dc-ac inverter with CLL resonant tank, also referred to as pi2a impedance matching network is analyzed, designed, and simulated to observe its superior performance over other topologies at varying coupling coefficients and loads. Four soft-switching rectifier topologies are analyzed, designed, and simulated to evaluate their behavior at high frequencies. Their compatibility with Class-E inverters in the presence of loosely-coupled transformers is discussed. The physical and commercial limitations of using transformers with magnetic core is presented. Therefore, the preferred solution, an air-core transformer is designed and integrated with the rectifier to evaluate their characteristics at selected coupling coefficient. The overall system including the inverter, loosely-coupled air-core transformer, and rectifier was designed for the following specifications: operating frequency 6.78 MHz, output power across a single-load 40 W, output voltage 25 V, and target coupling coefficient of 0.5. Simulation results have been provided to validate the theoretical predictions. The major challenges faced during the integration of these building blocks are addressed. Finally, conclusions, contributions, and scope for future work are provided.

Committee:

Marian Kazimierczuk, Ph.D. (Advisor); Saiyu Ren, Ph.D. (Committee Member); Yan Zhuang, Ph.D. (Committee Member)

Subjects:

Electrical Engineering; Electromagnetics; Electromagnetism; Engineering

Keywords:

Power converters; Inverter; Rectifier; Transformer; High frequency wireless power transfer; Impedance matching; Electrical engineering; Soft switching; ZVS; ZCS

Nees, Eric A.Design and Demonstration of a Physical, Multi-Agent Autonomous Controller Testbed
Master of Science in Electrical Engineering (MSEE), Wright State University, 2017, Electrical Engineering
Navigation and control algorithms are often tested in a simulated environment before being deployed in physical systems. Although simulated environments provide a controlled setting to carefully evaluate performance, the designed scenarios are sometimes unrealistically ideal and may unintentionally omit circumstances or unmodeled interactions. This thesis presents the design, implementation, and practical demonstration of a physical testbed that enables the testing of multi-agent autonomous strategies in hardware on a small scale. Testing the algorithms at scale allows real-time exploration of the interaction and performance of both human and autonomous algorithms under non-ideal conditions while avoiding the costs and risks of full-scale, deployed systems. Presented in the following is a detailed robot design for this explicit purpose, and the overall design of the testbed system including software. A dynamic game is evaluated using the described system, and the results are presented.

Committee:

Zachariah Fuchs, Ph.D. (Advisor); Josh Ash, Ph.D. (Committee Member); John Gallagher, Ph.D. (Committee Member)

Subjects:

Electrical Engineering; Robotics

Keywords:

electrical engineering; robotics

Boyd, Joe ThomasLinear and nonlinear spectral analysis of the dynamics of a Q-switched laser pulse /
Doctor of Philosophy, The Ohio State University, 1969, Graduate School

Committee:

Not Provided (Other)

Subjects:

Engineering

Keywords:

Electrical engineering;Lasers;Spectrum analysis

Compaleo, Joshua DavidSplit Ring Resonator Design for Agricultural Based Applications
Master of Science in Electrical Engineering (MSEE), Wright State University, 2015, Electrical Engineering
Recent advances with manufactured electromagnetic materials known as metamaterials are paving the way to use microwave technology in agricultural development and harvesting. It has been proposed that split ring resonators could be placed on the surface of fruit or vegetables such that the resonant behavior may be monitored and used to estimate the ripeness level. The method is non-destructive and could enable monitoring of large quantities of produce or even be tailored to hand-held devices for consumers. However, the understanding of corresponding changes in the proposed device’s resonant behaviors and ripeness levels are limited. In addition, fruit and vegetables are highly lossy at microwave frequencies making it difficult to establish resonant behavior. Here, the split ring resonator design is studied to determine which design parameters are most influential on maintaining a resonant behavior in the presence of highly lossy media. The results show that for small array sizes, the radial spacing between the rings and the radial widths of the microstrip rings have the most significant influence. However, resonance is only achievable in the presence of low to moderate loss levels. The results also suggest that a large array of resonators may be sufficient to maintain resonance at the loss levels of certain fruit.

Committee:

Michael Saville, Ph.D. (Advisor); Fred Garber, Ph.D. (Committee Member); Yan Zhuang, Ph.D. (Committee Member)

Subjects:

Electrical Engineering

Keywords:

electrical engineering

Chauhan, ShwetaHysteretic controlled DC-DC converters
Master of Science in Engineering (MSEgr), Wright State University, 2014, Electrical Engineering
Switched-mode DC-DC converters are widely used in applications requiring step-up and step-down of DC voltages or currents. These converters find their use in portable applications such as laptops and smart phones, radio-frequency power amplifiers, as light emitting diode (LED) drivers, etc. The power converters consist of a switching network, energy storage elements such as inductors and capacitors, and a load resistor. Transformers are used in converters, which require isolation. The switching network comprises of MOSFETs and diodes. With improvement in the VLSI technology, smaller MOSFETs with increased power handling capability are pushing the speed of operation of these power converters to the gigahertz (GHz) range. Operation at such high frequencies not only requires energy-efficient semiconductor switches, but also demands for faster control mechanisms. Amongst the various power converter control schemes studied in literature for high-frequency applications, the hysteretic control scheme is given high importance. The hysteretic controller employs a basic operational amplifier (op-amp) and works similar to the Schmitt trigger with hysteresis. Also, the bandwidth of op-amps is theoretically infinite and can be designed with ease for many applications, making the hysteretic controller scheme, simple and widely used method. This thesis focuses on understanding the operation and characteristics of the hysteretic control scheme. Initially, a buck DC-DC pulse-width modulated (PWM) converter is used as the power stage and the hysteretic controller is designed to ensure proper regulation of the output voltage of the buck converter. Two different types of hysteretic control mechanisms, namely (a) dual-charging mode and (b) capacitive-charging mode are investigated. The equations necessary to design the controller for both modes are derived. Extensive simulations are performed in order to evaluate the load and line regulation with and without the controller. Further, similar analysis is performed using a boost DC-DC PWM power converter as the power stage. Various characteristics such as percentage load regulation (LOR), percentage line regulation (LNR), and total harmonic distortion (THD) are estimated for buck converters.

Committee:

Marian Kazimierczuk, Ph.D. (Committee Chair); Kuldip Rattan, Ph.D. (Committee Member); Yan Zhuang, Ph.D. (Committee Member)

Subjects:

Electrical Engineering; Engineering

Keywords:

engineering;electrical engineering

Lipstreu, William F.Digital Signal Processing Laboratory Using Real-Time Implementations of Audio Applications
Master of Sciences (Engineering), Case Western Reserve University, 2009, EECS - Electrical Engineering

In the 21st century, digital signal processing (DSP) is at the core of most technologies which either directly or indirectly rely on the representation and processing of digital data. All engineering disciplines in this information age need to have a basic understanding of how data from real-world experiments and systems are acquired and processed to extract usefulinformation.

In most college curricula, there are a myriad of DSP textbooks and courses that are typically accompanied by complex mathematical proofs and theoretical derivations. However, it is important to integrate classroom concepts with hardware implementations to give students experience with real world applications. Synthesizing design parameters and translating them to work within the confines of a real-time system is an invaluable and necessary skill for modern engineers.

In this thesis, we develop a comprehensive set of laboratory experiments to demonstrate the theory and applications of digital signal processing through the means of audio applications.

Committee:

Kenneth Loparo, PhD (Committee Chair); Marc Buchner, PhD (Committee Member); Vira Chankong, PhD (Committee Member)

Subjects:

Electrical Engineering

Keywords:

digital signal processing; electrical engineering; laboratory course; audio applications

Patel, Rishit NavinbhaiImplementation of High Speed and Low Power Radix-4 8*8 Booth Multiplier in CMOS 32nm Technology
Master of Science in Electrical Engineering (MSEE), Wright State University, 2017, Electrical Engineering
According to Moore’s law, number of transistors integrated on a single chip double every 18 months with a lot new functionality embedded, which results the increasing of delay and power consumption of a chip. To improve the performance of a more complicated digital circuit design, faster and power efficient digital sub-components are in urgent need. Multipliers are the key components in the field of DSP, GPU and CPU which compute enormous amount of binary data. A radix-4 8*8 booth multiplier is proposed and implemented in this thesis aiming to reduce power delay product. Four stages with different architecture are used to implement this multiplier rather than traditional 8*8 booth multiplier. Instead of using adder in stage-1, it is replaced with binary-to-access one converter circuit and 10-bit MUX 2:1 to reduce power consumption by 23.76% and increase speed by 12.02% compared to stage-1 of traditional 8*8 booth multiplier. This proposed design is implemented in CMOS 32nm technology at 1.0 voltage supply. The worst-case delay of the proposed radix-4 8*8 booth multiplier at 2 Giga data rate is 423 picosecond and power consumption of 0.274 milli-watts with transistor count of 2860.

Committee:

Saiyu Ren, Ph.D. (Advisor); Ray Siferd, Ph.D. (Committee Member); Jiafeng Xie , Ph.D. (Committee Member)

Subjects:

Electrical Engineering

Keywords:

electrical engineering

Levine, DanielSummability methods and amplifier gain curves
Doctor of Philosophy, The Ohio State University, 1955, Electrical and Computer Engineering
N/A

Committee:

F.C. Weimer (Advisor)

Subjects:

Electrical Engineering

Keywords:

Electrical engineering

Sanderson, JoshHierarchical Modulation Detection of Underwater Acoustic Communication Signals Through Maximum Likelihood Combining
Master of Science in Engineering (MSEgr), Wright State University, 2014, Electrical Engineering
Modulation detection is important to many communication applications. Much research has been done in this area for radio frequency (RF) signals, but until recently little has carried over to the underwater communication world. Traditional methods include the use of fourth order cumulants or second order cyclostationary features to determine the modulation scheme being used. Many of these methods fail due to the complex and varying nature of the underwater channel. This thesis proposes a new form of hierarchy modulation detection for underwater acoustic communication signals using maximum likelihood combining. The proposed method for hierarchical modulation detection for this research is a two-step process. The first step uses cyclostationary features which are insensitive to the many of the effects of the underwater channel and will provide a useful way to classify between BPSK and higher order modulation schemes. The next step will use maximum likelihood combining to determine whether the non-BPSK signals are QPSK or 16QAM. The use of noncontiguous block spacing can also help improve the probability of correct detection. Two methods were implemented and tested to find the correct modulation, averaging and voting. For averaging, the mean of multiple blocks were combined and a decision made on the result. For voting, a decision was made for each block, and the majority decision was chosen. Using underwater acoustic communication data, a high degree of accuracy is achieved for modulation detection of BPSK, QPSK, and 16QAM signals. The best result occurred for the averaging method combining three noncontiguous blocks, where the correct modulation was detected to be 94:23 for BPSK, 91:54 for QPSK and 90:77 for 16QAM. The proposed method overcomes the effects of the underwater channel with a high probability of correct detection using real captured sea data.

Committee:

Zhiqiang Wu, Ph.D. (Advisor); Frank Zhang, Ph.D. (Committee Member); Bin Wang, Ph.D. (Committee Member)

Subjects:

Electrical Engineering

Keywords:

electrical engineering

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