Engineering Commons^™

Voltage Dip Mitigation For Motor Starters Using An Adaptive High Speed Relay Protection On The High Voltage Transmission System, Cesar Alberto Rincon

LSU Master's Theses

Currently, the aging state of the protection systems for industrial facilities is calling for a system-wide review of the equipment and the protection schemes used in all these places, calling for a new approach in the design and implementation of these systems. Some of these facilities house critical processes that can be seriously affected by a misoperation of equipment or a disturbance in the system, aspects ranging from safety of plant workers to millions of dollars in loss of production. In this thesis different contingency situations were explored for problems in the utility transmission system that could affect large industrial …

Simultaneous Rf/Eo Tracking And Characterization Of Dismounts, Jason M. Blackaby

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This thesis discusses the fusion of radar frequency(RF) data and electro-optical (EO) data for tracking and characterization of dismounts (i.e., humans). Each of these sensor modalities provides unique information about the location, structure, and movement of a dismount. The person's location is tracked on the 2D ground plane using RF data for range measurements and EO data for angle measurements. Using this information, measurements are made on the structure and dynamic motion (gait) of the person. An imaging approach is used to create spatio-temporal activity maps along with a three-dimensional reconstruction of the dismount.

Intelligent Spectrum Sensor Radio, Omer Mian

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A cognitive radio is a radio with built-in intelligence that makes it able to utilize the radio frequency spectrum more efficiently by adapting to the changing conditions and frequency availability. In this thesis a spectrum sensor radio is designed that detects transmissions in FM band and determine the range of used and unused frequencies within the band. The radio then starts a transmission on a frequency among the available frequencies. This intelligent radio system design is implemented using the Universal Software Radio Peripheral and GNU Radio with a program written in python that uses a number of GNU Radio modules …

Gps Coarse Acquisition Using The Monobit Fft Algorithm In A Broadband Receiver, John Flynn

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The purpose of this research was to investigate the feasibility of using broadband electronic warfare (EW) receivers for Global Position System (GPS) tracking. These are pulse-oriented receivers, typically with input bandwidths of 1 Ghz or larger, and so by definition do not have the same characteristics and processing of continuous wave (CW) receivers like GPS devices, FM radios, etc. For example, the spectral output of the Fast Fourier Transform (FFT) used in broadband signal processing updates on the frequency of the FFT input sample size, versus a CW receiver which updates on a more continuous basis.

The foundation of this …

Design Of A Cmos Rf Front End Receiver In 0.18Μm Technology, Vishwas Kudur Sastry

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An RF front end receiver system refers to the analog down conversion stages of the wireless communication system. The Digital base-band signals cannot be transmitted directly through wireless channels due to the properties of electromagnetic waves. The baseband signals need to be converted to analog through a digital-to-analog converter (DAC), up converted to higher frequency using an up conversion mixer and then transmitted through the channel. The received signals are down converted to base band frequency and then converted to digital again using the analog to digital converter (ADC). The processes which the analog signal undergoes at the RF front …

Costas Pll Loop System For Bpsk Detection, Rajesh Kumar Keregudadhahalli

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A 2GHz carrier recovery Costas Loop based BPSK detector is designed using CMOS 0.18μm technology. The designed BPSK detector consists of single to differential conversion circuit, phase/frequency detector, Voltage Controlled Oscillator, differential to single conversion circuit, first order loop filter and a third multiplier. Different architectures available for each block have been discussed along with the design methodology adopted. The schematics were simulated in analog design environment.

The Costas loop presented in this work can sense both 0° and 180° phases at its input. Thus the Costas loop carrier recovery circuit overcomes the 180° phase ambiguity presented by the conventional …

Fpga Design Of A Hardware Efficient Pipelined Fft Processor, Ryan T. Bone

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Digital receivers involve fast Fourier transform (FFT) computations that require a large amount of arithmetic operations. The implementation of a FFT processor is one of the most challenging parts in the realization of a wideband receiver and its hardware complexity is very high. Hence, kernel function FFT processors have been proposed to meet real-time processing requirements and to reduce hardware complexity by rounding the kernel function to predetermined kernel points so as to eliminate the multipliers and use only shifters and adders or subtractors. Because of the nonlinear nature of this approximation by the rounding errors, spurious responses are generated …

Ici Reduction Methods For Mc-Cdma Systems, Meng Wu

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Multi-carrier code-division multiple-access (MC-CDMA) is an important multiple access candidate for 4G wireless communication system. While MC-CDMA provides high performance and high capacity in frequency selective fading channels, it is very sensitive to the signal distortion, especially the Inter Carrier Interference (ICI). We apply self-cancelation and a frequency transmission paradigm to MC-CDMA system to improve the sytem performance in an ICI rich environment. Furthermore, we combine the frequency transmission paradigm FD-MC-CDMA with ICI cancelation. Also, we apply all these three schemes into non-contiguous OFDM and non-contiguous MC-CDMA systems in simple Cognitive Radio communication environments and present the simulation results. Theoretical …

Automotive Battery State-Of-Health Monitoring Methods, Ryan J. Grube

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Effective vehicular power management requires accurate knowledge of battery state, including state-of-charge (SOC) and state-of-health (SOH). An essential functionality of automotive batteries is delivering high power in short periods to crank the engine. A well-known approach to battery SOH monitoring is to infer battery state-of-health from battery impedance or resistance, which is not robust to variation of battery types. The research and development of more reliable battery state-of-health monitoring methods to ensure vehicle start-up ability are presented in this thesis. The methods include a battery cranking voltage based method, a parity-relation based method using battery voltage and cranking current signals, …

Implementation Of Null Conventional Logic In Cots Fpga's, Mohamad Rajgara

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The digital world has been dominated by the growth of synchronous digital design techniques for last few decades. Traditional Boolean logic is symbolically incomplete since it has a separate control logic, time in the form of clock signal which be carefully integrated with the logic design, but with digital clock signal already in the GHz range, this integration is further complicated. One approach to address post GHz digital logic design is to use clockless or asynchronous digital design techniques. In the mid '90s Theaseus Logic Inc. proposed a method to design Asynchronous circuits using Null Convention Logic (NCL).This thesis introduces …

Multiple-Input Multiple-Output Wireless Communications With Imperfect Channel Knowledge, Christopher Potter

Doctoral Dissertations

"In the first work a recurrent neural network (RNN) is employed for MIMO channel prediction. A novel PSO-EA-DEPSO off-line training algorithm is presented and is shown to outperform PSO, PSO-EA, and DEPSO. This predictor is shown to be robust to varying channel scenarios. New expressions for the received SNR, array gain, average probability of error, and diversity gain are derived. Next, a new expression for the outage capacity of a MIMO system with no CSI at the transmitter and an estimate at the receiver is presented. Since the outage capacity is a function of the first and second moments of …

Enabling Wind Turbine Generators To Participate In Power Grid Frequency Regulation For Enhanced Stability, Hongtao Ma

Doctoral Dissertations

"This dissertation focuses on wind farm frequency regulation capability to maintain the grid frequency stability. Wind plant power controllers are designed and tested for participation in grid frequency restoration. The small signal stability on sub-optimal operating points is analyzed and a de-loaded operating point is proposed.

In the first paper, a new frequency regulation scheme is developed for the wind turbine/generator/converter trio that will provide the capability to participate in restoring frequency in a way similar to the droop response of conventional generators. Output active power adjustment can be realized by both converter and pitch angle control in addition to …

Energy Efficient Wireless Sensor Network Protocols For Monitoring And Prognostics Of Large Scale Systems, James W. Fonda

Doctoral Dissertations

"In this work, energy-efficient protocols for wireless sensor networks (WSN) with applications to prognostics are investigated. Both analytical methods and verification are shown for the proposed methods via either hardware experiments or simulation. This work is presented in five papers. Energy-efficiency methods for WSN include distributed algorithms for i) optimal routing, ii) adaptive scheduling, iii) adaptive transmission power and data-rate control"--Abstract, page iv.

Real-Time Hilbert Transform And Autocorrelation For Digital Wideband Communication Applications, Murthy, Dilip Srinivasa

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Digital wideband receiver plays a key role in communication and radar systems, and it is used detect and analyze wide range of radio frequency (RF) signals. A digital Instantaneous Frequency Measurement (IFM) receiver is designed, where implementation of a real-time architecture of a Hilbert transform and autocorrelation algorithm is presented. Real-time architecture performs continuous monitoring and processing of the incoming signal. Prior to the previous one bit design, the input data fed to the Hilbert transform is 8-bit wide at a clock rate of 320 MHz with the input data rate is increased by a factor of eight, an 8-bit …

Design Of Pulse Output Direct Digital Synthesizer With An Analog Filter Bank, Aditya R. Pothuri

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Over the past two decades frequency synthesizer has progressed from a relatively crystal bank synthesizer to multi-loop phase locked loops. But in recent years direct digital synthesizers (DDS) have witnessed an increase in demand over their analog counterparts. The DDS offers a wide range of advantages over phase locked loops such as high frequency range, fast switching response, and sub-hertz frequency resolution. However, the conventional DDS suffers limitations due to its architecture involving digital-to-analog converter (DAC) and read-only-memory (ROM) with respect to high clock speeds.

The Pulse Output Direct Digital Synthesizer (PODDS) presented in this thesis eliminates the necessity for …

A Low-Cost Acoustic Array For Detecting And Tracking Multiple Acoustic Targets, Ellen E. Case

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A wide variety of real-world targets emit distinct acoustic signatures that not only distinguish them from one another but also provide spectral separation from background clutter. While acoustic signatures are distinct, they can also be highly variable, even for an individual target, making detection and tracking a challenging problem. This thesis presents a low-cost acoustic array using commercial off-the shelf (COTS) hardware to detect and track multiple small, moving, acoustic targets. It implements a cross-correlation method for calibration, delay-and-sum beamforming, CA-CFAR detection, a discrete Kalman filter for tracking, and nearest neighbor data association. In addition, the array is designed to …

An Algorithm For The Detection Of Handguns In Terahertz Images, Andrew J. Lingg

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This paper presents an algorithm for detecting handguns in terahertz images. Terahertz radiation is capable of penetrating certain materials which are opaque atoptical wavelengths, such as clothing, without the harmful effects of ionizing radiation. The approach taken is to segment objects of interest and classify them based on shape. We use a modified version of an active contour algorithm found in the open literature. Modifications include: a pre-processing step that includes clutter filtering and seeding of an initial contour; and a post-processing step that removes clutter pixels from the segmentation. The features used for classification are moment-based and Fourier shape …

Influence Of Voltage Source Pulse Width Modulated Switching And Induction Motor Circuit On Harmonic Current Content, Martin T. Lange

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The purpose of this research is to present analysis of the harmonic content present in the phase current of a three phase induction motor while being powered by a voltage source pulse-width modulated (PWM) variable speed drive (VSD). First, the topology and circuit of the drive, its operational fundamentals and waveform appearance are presented and discussed. Next, the three-phase induction motor circuit model and operational characteristics are discussed. Finally, the harmonic content present in the induction motor phase current is determined by use of the PSPICE model. The ability of the PSICE simulation to determine harmonic content is established. It …

Guidelines For Deploying Wireless Sensor Network In Manufacturing: Star Topology Study Using The Rssi To Test The Network Performance, A. Hameed Madwar

Dissertations and Theses @ UNI

Wireless Sensor Networks (WSNs) are varying in kinds and can be used for many purposes. It can be extensively used in monitoring, reporting, and decision routines. Therefore, WSNs are very important to integrate with manufacturing since they can help not only in monitoring and decision making but also they can increase productivity and decrease the wiring costs. However, WSNs are facing some challenges in manufacturing as they need to resist the interferences that could be generated by the electrical and mechanical fields created during the manufacturing processes. Some of these interferences could be due to the high temperatures, blocks of …

Physical Layer Secrecy Channel Coding, Bandali K. Akkawi

LSU Master's Theses

Wireless communications is expanding and becoming an indispensable part of our daily life. However, due to its channel open nature, it is more vulnerable to attacks, such as eavesdropping and jamming which jeopardize the confidentiality of wireless data, compared to its counter-part, wireline communications. Security in wireless communication is thus a very important factor that should be perfected to accommodate the rapid growth of wireless communication today. Motivated by information theoretic secrecy definitions, we adopt a simple way to define the secrecy of a system by looking at its Bit-Error-Rate (BER) curves, the correlation of error vectors and Log Likelihood …

Block Level Link Path Design And Multilayer Via Transition Model Assembly Using S-Parameters, Francesco De Paulis

Masters Theses

"In high-speed data communication systems the complexity of link path between transmitters and receivers present a challenge for designers to maintain an acceptable bit error rate. An approach is presented in this thesis to design the link path on a block-by-block basis. The unique advantage of this approach lies on the physics-based model of each block, which then relates performance to geometry and makes design improvement and optimization possible. A tool based on the manipulation of frequency domain data has been designed to help in the design and analysis process of fast communication systems. It accepts as inputs the frequency …

Derivation Of New Double-Input Dc-Dc Converters Using The Building Block Methodology, Karteek Gummi

Masters Theses

"In most power electronic systems, the instantaneous input and output power vary by time and are not exactly identical with each other. Hence, providing a good match between them is a complicated task to deal with if not impossible. Furthermore, due to the wide variation range of the processed power, the overall efficiency of the system is not high. The solution is to hybridize the system using an energy storage unit like in hybrid electric vehicles, power factor correction systems, and photovoltaic systems. Multi-input converters play a key role in such hybridized systems, where it is required to have more …

Fabrication Of Long-Period Fiber Gratings By Co₂ Laser Irradiation For High Temperature Applications, Tao Wei

Masters Theses

"Long period fiber gratings (LPFG) have unique advantages such as small insertion loss, low retro-reflection, good sensory property and low cost fabrication. LPFGs have found many applications in optical fiber communications as well as in optical fiber sensors. Recently, high-performance LPFGs have been successfully fabricated by CO₂ laser irradiations. The unique thermal stability enables many potential sensing applications in high temperature environments. In this thesis...two chemical sensing applications of LPFG were demonstrated. In the first one, the ambient refractive index sensing ability of bare LPFG was examined. The experimental data showed a good agreement with the simulation results. In the …

A Hybrid Sensor Network For Watershed Monitoring, John R. Koch

Masters Theses

"This thesis discusses the Hydrological Hybrid Communication Sensor Network (HHCSN), which is designed for in situ measurement of various hydrological properties of a watershed. HHCSN is comprised of a network of sensor strings, each of which connects up to 100 sensing nodes on a communication line as long as 100 m. Each node includes sensors that measure soil attributes of interest, as well as a microcontroller with basic communication and processing capabilities. A relay point at the surface compresses data from the nodes and wirelessly transmits it to a base station that serves as a gateway to the outside world. …

Universal Electric And Magnetic Fields Analyzer System, Yong Cheh Ho

Masters Theses

"Near-field probing is often used to measure the electric and magnetic fields above a printed circuit board (PCB) or integrated circuits (IC) chip in order to identify the sources and coupling paths of an electromagnetic interference (EMI) problem.

A wideband universal field analyzer was designed, built and tested in this thesis. The system is able to provide fast field scanning over a wide frequency range in lieu of its capabilities to measure multiple field components using a single probe design. Central to the system operation is the phase-shifting concept that provides wideband and wide- range phase-shifting.

The complete universal field …

Application Of Multi-Modal Fusion Techniques For Corrosion Detection And Characterization In Aging Aircraft Components, Soumya De

Masters Theses

"The United States Air Force (USAF) recently estimated that corrosion maintenance costs exceed $800M per year. Given this, it is desirable to reduce the amount of "find it-fix it" corrosion maintenance activities. One method is to introduce a damage tolerance approach for corrosion detection. In order for this to become a reality, a comprehensive snapshot of corrosion present must be generated.

This thesis presents a data fusion process to perform uni- and multi-modal nondestructive testing and evaluation of corrosion under paint and in lap joints for volumetric characterization. The process for analyzing a given structure includes: 1) the acquisition of …

Formation Control Of Car-Like Mobile Robots, Shweta Annapurani Panimadai Ramaswamy

Masters Theses

"A traditional tracking and control design approach already available in literature is derived and discussed for a car-like mobile robot. It involves a decoupled design involving two separate algorithms, one for velocity control design and another for torque control design. Weak interactions among the algorithms and separate designs make the robot performance optimization and the formation stability difficult to achieve. So, a new tracking and control architecture wherein the conventional elements are replaced by a single component that performs all the functions and hence called the integrated tracking and control scheme is used"--Abstract, page iii.

Application Of Statcom For Improved Dynamic Performance Of Wind Farms In A Power Grid, Aditya P. Jayam

Masters Theses

"This thesis investigates the use of a Static Synchronous Compensator (STATCOM) along with wind farms for the purpose of stabilizing the grid voltage after grid-side disturbances such as a three phase short circuit fault, temporary trip of a wind turbine and sudden load changes. The strategy focuses on a fundamental grid operational requirement to maintain proper voltages at the point of common coupling by regulating voltage. The DC voltage at individual wind turbine (WT) inverters is also stabilized to facilitate continuous operation of wind turbines during disturbances"--Abstract, page iii.

Statistical Estimation Of Crosstalk For Cable Bundles, Meilin Wu

Masters Theses

"Predicting electromagnetic interference problems for cable bundles early in the design stage is of significant value for both automotive and other industries. Effective methods are needed for predicting interference when little design information is known. The random variation in parameters like wire position in the bundle require that statistical variations be taken into account. In the first part of this thesis, a method to analytically predict the "reasonable worst-case crosstalk" within a cable bundle is proposed. The method uses the per-unit-length LC matrices associated with the cross-sectional geometry of the bundle to generate probability a distribution function for mutual inductance …

Thermal Characterization Of Dielectrically Isolated Bipolar Junction Transistor, Daewoo Kim

Electrical Engineering Dissertations

Since the integrated circuit (IC) was invented in 1960, the operating speed of semiconductor devices has steadily increased and the number of semiconductor devices in an IC chip has grown by a size reduction of the devices. This trend has lead to the rapid increase of power consumption and heat generation. As a result of this increase, thermal characterization of semiconductor devices has become more important.It is especially important to consider thermal characteristics of the dielectrically isolated complementary bipolar junction transistor (DIBJT) which offers many advantages. However, a major disadvantage of this device is an increase in self-heating. Because the …