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A Frequency Domain Digital Signal Processor For Laser Velocimeter Systems, Andreas Evangelos Savvakis

Electrical & Computer Engineering Theses & Dissertations

A new signal processor for laser velocimeter systems is proposed. The proposed processor incorporates automatic initialization, real time operation, and can efficiently process input signals comprised of as low as 150 photons, with mean oscillation frequency up to 100 MHZ, and input turbulence from 0 to 20%. A bank of digital bandpass filters is employed for the energy spectrum estimation of the input signal. A deterministic model is developed to describe the relationship between the filter output energies and the input signal parameters. The input frequency is estimated by linearly weighting the filter output energies. A spline function approximation approach …

Wind Streamline Ambiguity Removal Of Microwave Scatterometer Data, Hans W. Zaepfel

Electrical & Computer Engineering Theses & Dissertations

There is a class of satellite microwave scatterometers that return oceanographic information which includes wind vectors with directional ambiguity. The first part of the ambiguity removal process is to reduce the data to a directional ambiguity of 180°. This thesis shows that wind direction change contains the information required for streamline ambiguity removal and that syntactic pattern recognition techniques can be used to locate the areas of wind direction change. Spreading the information along the areas of wind direction change results in the removal of the streamline ambiguity. The algorithm is implemented and the results are presented showing that it …

Logic Simulation And Methodologies For Design For Testability, Ravi Shankar Prasad Mallampalli

Theses

This thesis describes the method used for developing the standard TTL blocks using the logic simulator SPLICE1. It also gives a comprehensive overview of methods which can be used for designing a circuit which is testable. A format called Electronic Design Interchange Format (EDIF) is also described as a tool which can be used for transporting design data in the VLSI indgstry.

Multi-H Continuous Phase Modulation : Its Properties And Analysis, Jyung-Cheng Chen

Theses

Multi-h CPM, a generalization of CPFSK and also one of the so-called Combined Modulation and Coding schemes, is useful in digital communication systems where both the bandwidth and power are constrained. The increased signal processing complexity, which can be viewed as the third communication resource, is used to trade for both power and bandwidth, and to approach the error-free communication promised by Shannon's theorem.

The transmitted multi-h CPM signal carries a coded sequence of continuous phase changes; the possible phase states form a cylindrical trellis in phase and time, in which the modulation indices are reused in a cyclical fashion. …

Focused Acoustic Wave (Faw) Channelizer, Dennis R. Pape, Andrew M. Bardos, Marc H. Popek, Manhar L. Shah

Electrical Engineering and Computer Science Faculty Publications

The architecture, operation, and performance of a new integrated acoustic RF channelizer are described. The all- acoustic device uses a phased array piezoelectric transducer to generate frequency dispersed bulk acoustic waves over a 500 MHz bandwidth. The waves are focused onto a 25 channel receiver electrode array by a cylindrical reflector formed on the opposing surface of the device. This channelizer has the potential of providing higher dynamic range than competing technologies. © 1986 SPIE.

The Modeling Of A Self-Oscillating Dc-To-Dc Converter, Frank Andrew Linkowsky

Theses

This thesis develops a model of a nonlinear self oscillating current-or-voltage step-up dc-to-dc converter. Expressions are given that predict the operation of the converter in the time domain and in the state plane. To verify these expressions, a large signal computer simulation technique [1] is used to compare theoretical results with actual measurements. This type of simulation allows a nonlinear switching converter to be modeled with a series of piecewise-linear operating intervals. The resulting waveforms predicted by the developed model show close agreement with waveforms found in the laboratory. Therefore, the model represents a powerful tool that may be used …

Gallium Film Formation By Ion Cluster Beam Deposition, Te-Chuan Hsu

Theses

Gallium thin films were deposited by Ion Cluster Beam (ICB) from pure gallium. This research had two objectives: to develop a practical method of crucible heating to generate gallium clusters; and to investigate the influence of ICB system parameters on the formation of clusters and film properties. An electron-bombardment crucible heater with a novel construction was designed. The top section of the carbon crucible was kept at a higher temperature than the middle section to prevent clogging of the nozzle and " spitting " phenomena which were found to occur with the conventional design. Crucible temperatures up to about 1360°C …

Relationship Between The P And S Fresnel Reflection Coefficients Of An Interface Independent Of Angle Of Incidence, R. M.A. Azzam

Electrical Engineering Faculty Publications

The Fresnel reflection coefficients r_p and r_s of p- and s-polarized light at the planar interface between two linear isotropic media are found to be interrelated by (r_s - r_p)/(1 - r_sr_p) = cos 2β, independent of the angle of incidence ø, where tan²β = ∊ and ∊ is the (generally complex) ratio of dielectric constants of the media of refraction and incidence. This complements another relation (found earlier), (r²_s - r_p)/(r_s - r_sr_p) = …

Measurements Of Basic Semiconductor Properties, Abdolreza Ariantaj

Theses

Mobility, resistivity, and total impurity concentration of several purchased p-type silicon samples with known resistivities were measured by Hall effect, experiments utilizing the Van Der Pauw method. The silicon samples will serve as Hall effect standards for future measurements on other semiconductor materials, particularly gallium nitride ion cluster beam (ICB) deposited thin films. The samples which were Freshly etched with hydrofluoric acid had measurement values of 455 cm ² / V.sec, 45.9 Ω cm, and 2.6 X 10¹⁴ cm³ for mobility, resistivity, and total impurity concentration, respectively. The mobility values were within 9.9 per cent, of the published values …

The Acquisition Of Direct Sequence Spread Spectrum Communication Systems, Anthony Donald Demeri

Theses

This Paper surveys different techniques of acquiring Direct Sequence Spread Spectrum Systems.

It classifies different systems, indicates the strongpoints and weakness of each, along with some applications.

One method, The Single Dwell Serial PN Acquisition System is then focused on in detail. The detail includes analysis of standard version, derivation of the mean time to acquire, the variance, the probability of detection and the probability of a false alarm.

In the last section of the paper the analytical results of the Single Dwell Serial PN Acquisition System shall be confirmed by computer simulation.

Reliability Studies On Solid Tantalum Electrolytic Capacitors By Means Of Accelerated Life Tests, Venkata R. Golthi

Theses

The purpose of this thesis is to understand the failure mechanisms in Solid Tantalum Capacitors encapsulated in plastic, and to suggest the precautionary measures that prevent the occurrence of these failures.

The reliability of Solid Tantalum Capacitors encapsulated in plastic is of considerable interest because in some applications where the mechanical accelerations or shocks are considerable the "better" "hermitically" sealed type are not able to sustain themselves. Poor adherence between the dielectric film and the base metal Tantalum under the conditions of sudden mechanical shocks, causes problems.

Our study was carried out in two different directions, theoretical and experimental. The …

Reliability Study Of Liquid Crystal Display, Kalpesh Mahendra Desai

Theses

The purpose of this thesis is to study the reliability of liquid crystal display under different temperature conditions. To accomplish this, accelerated life testing was done on the soft glass and the hard glass liquid crystal display units at 77 C and 85 C temperature without any added humidity or voltage.

As the current is a usefu1 indicator for probable wear of liquid crystal display, leakage current was measured at 0 hour, 1000 hours, 2000 hours and 3000 hours when the units have stabilized at room temperature.

The date shows higher spread for the hard glass units. This may indicate …

The Dielectric Slab-Wedge Antenna, B. Keith Christensen

Theses

A theoretical model and numerical investigation of the directive gain of a dielectric slab-wedge radiator is presented. The model is based on a union of the classical dielectric slab equations, local mode theory, and equivalent current distribution treatments of the truncated dielectric slab and wedge geometries.

The far field is developed from the sum of two current distributions. The slab region, up to the transition plane between slab and wedge, is replaced by equivalent electric and magnetic surface current densities. The wedge contribution is developed from a volume polarization current distribution.

Conservation of power is used to approximate the field …

Replacement Of Surface Ducted Rays Near Caustics With Guassian Beams, Carlos Javier Ruiz

Theses

Conventional approach to a solution of a wave propagation problem in an inhomogeneous medium is to utilize either rays or modes to represent the wave field. Asymptotic ray theory (ART) starts to fail in the vicinity of caustics due to rays experiencing many reflections. Even uniform representations do not properly correct this deficiency of rays when caustics start to pile up in the far range. One possible alternative is to replace these rays with modal bundles and remainders [1]. A promising technique using Gaussian Beams has been used to represent the total field due to a point or a line …

Ray And Beam Representation Of The Glancing Phenomena, Michael Sotiriou Vogas

Theses

Asymptotic ray theory (ART) is a widely used method dealing with problems of wave propagation in an inhomogeneous medium. The main deficiency of ART is in transition regions where rays near caustics, glancing and critical incidence fail to represent the actual wave field. Ray bundles in such transition regions have been successfully replaced with modal bundles and remainders El] in well defined profiles. However , in practical problems it is difficult to implement modal representations and almost impossible to express remainders. Recently emerging Gaussian beam method (GBM) has shown promising results in representing the total field produced by a source …

Multi-Channel Arrhythmia Analysis In The Clinical Exercise Electrocardiogram, Shi-Xiong Yang

Theses

This thesis studied methods of using 2 channel ECG signals for noise elimination and arrhythmia detection. Clinical data were recorded from patients stress tests and were stored on diskettes for off-line processing. Spatial velocity vector and noise estimation methods in addition to analog and digital filters were combined to remove the noise produced from different sources. Feature extraction and matched filter methods were employed for classification of normal and abnormal QRS complexs, while rhythm computing was used in addition for PVCs and other arrhythmia discrimination. This algorithm was tested on clinical stress test recordings and a computer simulated arrhythmia recording …

Microcomputer Local Area Network Interface, David W. Juan

Theses

A Microcomputer Local Area Network Interface system for use in the study of Local Area Network has been built and tested. The special feature of the system is data transmission/receiving and error detection/recovery. The system adapted the International Standards Organization (ISO) Open System Interconnection COSI) model. It used the star topology and implemented the physical layer, data link layer and network layer. The results of the system indicated the data communications and resources—sharing between microcomputers.

Waveform Analysis Using A Micro Computer, Dakshina K. Murthy

Theses

Harmonic analysis through a micro computer was performed at Brookhaven National laboratory to determine the magnitude and extent of hormonic dIstortionon in their electrical power supply system. DT 2801 Hardware and MADCAP software were used to accomplish the Harmonic anylysis through forier transform.

Design And Evaluation Of Performance For The Multi-Microprocessor System, Sang-Soo Lee

Theses

A tightly coupled multiple-microprocessor with two MPU's that can be run at different clock speeds has been built and tested. The method of interconnection for this multiprocessor is a timeshared common bus with shared memories having a tightly coupled architecture. The signal timipg of the multiprocessor system for different speeds has been investigated using a logic analyzer for simulation modeling. The desired timing results have been obtained. According to the timing results, the simulation model for the General Purpose Simulation System has been correctly designed and performance of the multiprocessor system for the various clock speeds has been evaluated by …

Effect Of Humidity And Moderate Temperature On Microcircuit Failure, Antoine Mikhayel Chaia

Theses

The increased use of microprocessors has brought forth many questions concerning the reliability of these devices.

This research discuss the TTL integrated circuit failure rates, and provides information on the effects of temperature, device complexity and packaging on TTL failure rates under storage condition of 100% R.H. (Relative Humidity) and 100°C and no added humidity at 100°C. Other factors which can affect failure rate are also discussed, including designs, materials process.

Approximately 200 microcircuits of TTL (74LS00) were subjected to extend life testing at 100°C; where 125 chips are tested at 100°C ± 2° and no added humidity and the …

Nervous System Simulation, Jian Chen

Theses

This thesis deals with the nervous system simulation. The Hodgkin-Huxley model and Stein's model are used as basic tools. The author has tried to describe some practical problems by mathematical models.

First, the horse-shoe crab eye is investigated. Light intensity is reported to the brain by the firing frequency of the photoreceptoe. A Poisson process is used to simulate the stimulus to the receptor. The result of the stochastic model coincides with the theoretical one: receptor overlapping decreases the resolving power of the eye; and the lateral inhibition compensates the effect of overlapping.

Second, a nerve muscle model was set …

An 8052 Ah - Basic, Based Development System, Suresh Vishwanath Leley

Theses

This project exploits the latest in microcontrollers-an entire environment for developing and prototyping a microcontroller application. With one key chip, a little glue, and a Dumb terminal a powerful system is achieved at a vanishingly small cost. This "one chip" system is adequate for realizing a wide range of applications calling for a small computer or an embedded processor.

Besides economy of system cost, the turn around time from concept to functioning application can be extremely short, even when the development engineer is not particularly well acquainted with traditional assembly language and microprocessor development practices. This economy is achieved by …

An Analysis Of Minimum Shift Keying From The Viewpoints Of Quadrature Multiplexed And Multi-H Continuous Phase Modulation Signaling, Alfred Anthony De Seta

Theses

Minimum Shift Keying (MSK) is a bandwidth efficient modulation scheme which offers superior performance over Quadrature Phase Shift Keying (QPSK) and Offset Quadrature Phase Shift Keying (OQPSK). This paper discusses these modulation techniques from a quadrature multiplexed signaling viewpoint and compares them in terms of error performance, bandwidth properties and bandlimiting and hardlimiting effects. MSK is also considered as a special case of a multi-h Continuous Phase Modulation (CPM) signal and the Viterbi algorithm is presented as an optimal detection scheme for this class of signals. A computer simulation is performed with the VA as the detection mechanism for an …

A Computer Aided Manufacturing System For Small Quantity Prototype Board Production, Santiago Garcia-Perez

Theses

A matrix addressed manufacturing tool has been built, tested, and integrated in a system aimed to exploit wire-wrap wiring technology for protoboard production in small quantities. Extensive software exploits the power and economy of the personal computer as a superb manufacturing tool and documentation system. Computer graphics are used as a visual aid that takes advantage of the cognitive capabilities of the human mind and eliminates the boredom and high costs involved with heavy automation achieving instead a tolerable level of human engagement with significantly increased efficiency. The approach presented is new and delivers substantial gains in productivity. The software …

Realization And Implementation Of A Recursive Digital Convolution Algorithm In Cmos, Lik Tang Cheng

Theses

This thesis describes the implementation of a digital convolver. A recursive digital convolution algorithm was realised and implemented by using CMOS circuitry. This thesis also gives a technical overview of current CMOS processing technologies as well as various novel CMOS logic circuit techniques.

Design And Applications Of A Graphics Package For The Hp1000 Computer., Hsiao-Chih George Lee

Electronic Theses and Dissertations

The objective of this thesis is to develop the FORTRAN subroutine PLOTER which is a general-purpose plotting tool to plot charts on a Hewlett Packard plotter. The programs RESP and INVLAP which can plot the frequency and time responses of system functions are modified to adopt the PLOTER subroutine and are stored of the HP1000-A900 minicomputer whose software, the GRAPHICS/1000, supports the graphics ability of PLOTER. This thesis describes the theories, functions, software techniques and operations of the PLOTER subroutine and the application programs RESP and the INVLAP. It also provides program listings and example plots.

Two-Step Optimal Thermal Generation Scheduling, B Fardanesh, F. Eugenio Villaseca

Electrical and Computer Engineering Faculty Publications

A new approach to the solution of the optimal thermal generation scheduling problem is presented. The problem is solved in two steps. As a first step, the optimal production schedule for the next day is obtained based on a daily load forecast, reserve capacity requirements, and present status of generating units. The second-step algorithm uses the results of the first step and adjusts the previous schedule to meet new constraints developed during the course of the day. Variable truncation dynamic programming is proposed as a new method to reduce computation effort. To eliminate the need for solving the …

A Unit Of Instruction In Fiber-Optic Communication, Ronald Struble

Graduate Research Papers

The purposes of this research project were to:

1. Review the historical developments, components, and applications of optical fiber in communications.

2. Develop a laboratory exercise to demonstrate fiber-optic communication.

3. Construct equipment to demonstrate the use of fiber optics in communication. This equipment is used in the laboratory exercise.

Design Of Code Division Multiple Access Systems, Nakrendrakumar Patel

Theses

The intent of the work "Design of Code Division Multiple Access systems (CDMA) " is to consider different aspects of design with their effect on system performance. The generation of binary shift register sequences, that is maximal length sequences, with their properties are presented. From these maximal length sequences the Gold codes are obtained which are the most suitable approximately orthogonal codes for designing CDMA systems. These are discussed with their specific crosscorrelation properties. An extensive discussion is given of the difficult problem of synchronization, thatis bothacquisitionandtracking of pseudonoise sequences. Different synchronizing methods are discussed along with their relative performance. …

Optimization Of Reactive Ionized Cluster Beam (R-Icb) Technique For Deposition Of Gan Films, Veronica S. Kyriacou

Theses

The deposition of GaN film onto glass substrate, using the Reactive - Ionized Cluster Beam deposition technique was studied. The creation of clusters is dictated by various parameters such as the vacuum pressure inside and outside the crucible, the crucible temperature, and the nozzle diameter of the crucible. Optimization of these parameters was experimentally studied, and deposition of gallium films on glass substrates was tried as a first step.

The direct heating method was used at first to get the 1100¬1300°C crucible temperature which was required for the creation of gallium clusters. Although different tungsten wire diameters and different number …