Electrical and Computer Engineering Commons^™

A Piezoelectric Actuated Scanning Mirror System Utilizing A Type One Control Loop, David Gibbs

Retrospective Theses and Dissertations

The purpose of this thesis is to design and build an improved control loop for a piezoelectric actuated scanning mirror system. A control system has been built having zero steady state position error and an 80 Hertz bandwidth. This was achieved by placing the piezoelectric actuator in the feedback path of an operational amplifier and placing series cascaded notch filters and lead compensators in the forward path of the control loop. A prototype system, including compensation and feedback, is developed. Its performance compares favorably with that of the system model. It is capable of plus and minus 1.7 degrees of …

Barium Borate In Parametric Oscillation And 1.54 Micron Generation, Mark Kerrigan

Retrospective Theses and Dissertations

As to date, there are several relatively new crystals that have been developed for nonlinear or "parametric" optical applications, including KTP, LAP, KNbO3, m=NA, and BaB204 (barium borate, or simply BBO). The latter crystal, BBO, and the use of BBo to achieve parametric oscillation around an eyesafe wavelength of 1.54 microns is the emphasis of this paper.

Unpublished material includes determining the optimum type of coupling and pump wavelength used when generating 1.54 μm eyesafe radiation based upon Poynting vector walk off, suscpetibilityies, and both signal angular and spectral acceptance widths. Poynting vector walk off curves for linearly polarized extraordinary …

Uniform Energy Discharge For Pulsed Lasers, Eric Calvin Koschmann

Retrospective Theses and Dissertations

The art of achieving a large energy discharge in a controlled manner with relative ease is to use a pulse forming network. Historically the design of such networks generally used a single inductor and capacitor. Although easy to design and implement, this practice does not provide optimum performance in all cases. In particular, most laser welding requires a uniform energy discharge in a pulse to produce a high quality weld. Analysis has shown that when the pulse forming network approximates a lumped constant transmission line a maximum flat pulse is produced with minimal degradation of the pulse rise time. This …

Three-Level Block Truncation Coding, Deborah Ann Lee

Retrospective Theses and Dissertations

Block Truncation Coding (BTC) techniques, to date, utilize a two-level image block code. This thesis presents and studies a new BTC method employing a three-level image coding technique. This new method is applied to actual image frames and compared with other well-known block truncation coding techniques.

The method separates an image into disjoint, rectangular regions of fixed size and finds the highest and lowest pixel values of each. Using these values, the image block pixel value range is calculated and divided into three equal sections. The individual image block pixels are then quantized according to the region into which their …

Design Of A Bandpass Oculometer, Karin Brandauer

Retrospective Theses and Dissertations

A passive oculometer is a device that measures the position of the eye by utilizing the corneo-retinal potential (CRP) generated by the eye. In this thesis, the Bandpass Oculometer replaces the joystick of a personal computer, allowing the viewer to use a computer simply by moving his eyes. Low frequency noise, present in all electronic circuits, produces an offset from the reference point, the center of the screen. In previous lowpass oculometry studies at University of Central Florida, this offset caused the cursor to drift toward the edge of the field of view within a period of 30 seconds, decreasing …

Computer Aided Design Of Linear Phase Finite Impulse Response Digital Filters, Wentao Lyou

Retrospective Theses and Dissertations

This research report is an investigation of techniques for designing linear phase finite-duration impulse response (FIR) filters. The software package, CADFIR, developed for this project can be used to design linear phase FIR digital filters via three well-known design techniques: the window method, the frequency sampling method, and the optimal filter design method. CADFIR has options for designing such standard filters as lowpass, highpass, bandpass, and bandstop filters as well as multipassband-stopband filters. The fundamental properties of FIR filters are discussed and design algorithms associated with the three FIR filter design techniques are developed. Design examples are included and the …

Numerical Analysis Of The Resonant States Of Quantum Wells And Superlattice Devices, Alan Gilbert Whittaker

Retrospective Theses and Dissertations

This thesis is concerned with the development of a numerical model to describe the resonant states associated with quantum well and superlattice devices. A numerical method is described where the time-independent Schrodinger equation is represented as a series of simultaneous algebraic equations using the finite-element method. The eigenvalues for these equations are then found using a Sturm sequence, and the eigenfunctions subsequently calculated using a reverse iteration method containing orthogonality constraints. Simulations of specific devices are presented and compared with experimental results and good correlation is observed.

Analysis Of Phase Noise In Phase Lock Loop, Diane Marie Pavik

Retrospective Theses and Dissertations

This research report presents an introduction into phase lock loops (PLL) with a major emphasis on calculating phase noise in frequency synthesizers. A PLL model that incorporates the major sources of noise is presented for the purpose of design analysis. The model can be used to analyze second and fifth order PLLs which allows the accurate calculation of phase noise as a function of independent variable design parameters. The stability of PLLs is also analyzed to show the effects of a marginally stable system on the resultant phase noise. Developing an accurate PLL model which accounts for the major sources …

Surface-To-Surface Transition Via Electromagnetic Coupling Of Coplanar Waveguides, Robert W. Jackson, David W. Matolak

Faculty Publications

A transition is investigated which couples coplanar waveguide on one substrate surface (a motherboard) to coplanar waveguide on another substrate surface (a semiconductor chip or subarray) placed above the first. No wire bonds are necessary. A full-wave analysis using coupled line theory is presented and verified experimentally. The use of this transition for coupling to millimeter-wave integrated circuits is discussed.

Optically Phased Laser Transmitter, Janet S. Fender, Salvatore J. Cusumano, Robert R. Butts, Christopher R. Dehainaut

AFIT Patents

An apparatus and technique are described for phasing the outputs of a multiplier telescope array used as a laser transmitter. The technique uses samples of the transmitted beams to control optical path lengths through the separate telescopes so that the beams add coherently at the receiver. The phasing concept is applicable both to systems which provide inputs to the multiple telescopes by dividing a single laser beam and to systems in which the inputs to the telescopes and multiple, phase-locked laser beams. The approach is also compatible with single line and multi-line lasers, and it does not entail stringent alignment …

Ada Tools For The Description And Simulation Of Digital Signal Processing Systems, Mark D. Happel

Retrospective Theses and Dissertations

While specialized hardware description languages allow for maximum capability and efficiency in a design automation system, the use of a general purpose language in the same role can make the system more available or more available or more practical for a larger set of users. This project demonstrates the use of ADA* for the description and simulation of small digital signal processing systems. Building on conventions and primitives proposed by Denyer and Renshaw, a simple subsystem was described in ADA and then tested with a small simulator also written in ADA.

* ADA is a trademark of the United States …

Computer Simulation Of Dynamic Systems, Charles G. Smith

Retrospective Theses and Dissertations

Computer simulation of a control system is a valuable tool in design or performance evaluation. This is especially true when non-linear elements cannot be ignored and must be included within the model. A general purpose block diagram oriented simulation program will be developed which can utilize continuous, discrete and non-linear building blocks. The software tool will be demonstrated by means of an example.

Compiling Unit Clauses For The Warren Abstract Machine, George D. Herbert

UNF Graduate Theses and Dissertations

This thesis describes the design, development, and installation of a computer program which compiles unit clauses generated in a Prolog-based environment at Argonne National Laboratories into Warren Abstract Machine (WAM) code. The program enhances the capabilities of the environment by providing rapid unification and subsumption tests for the very significant class of unit clauses. This should improve performance substantially for large programs that generate and use many unit clauses.

The Design Of A Resonant Post Waveguide Filter, Ramjee Prasad

Tanzania Journal of Engineering and Technology (TJET)

A seven stage, quarter-wave coupled, single post, resonant cavity type waveguide filter has been studied. The posts are placed according to the Tchebyscheff distribution. The filter is designed and fabricated to meet the following specifications: Centre frequency: 9.31 GHz, Number of stages = 7, 3-dB bandwidth = 300 Mhz, Ripple tolerance in the passband = 0.5 dB. The frequency behaviour of this filter has been experimentally studied and is in close agreement with the specifications.

Gain Margin And Phase Margin Interrelationships, M Luhanga

Tanzania Journal of Engineering and Technology (TJET)

The gain margin and the phase margin Of a control SY Stem are important parameters in the determination of the relative stability of control system. In this paper We derive general interrelationships between these parameters.

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.

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.

Data Structure Implementation And Investigation For A Prolog Language Interpreter, Hector Iurcovich

Retrospective Theses and Dissertations

A developmental Prolog language interpreter is constructed in the C programming language. The data type format is a subset of that of the Project Aquarius Prolog Engine proposed and under development at the University of California, Berkley. The design of the Prolog interpreter is part of an investigation at UCF in design of expert system architecture for real time applications. The interpreter facilities of data structure definition and manipulation are developed and applied. The list data structure is used as an example data structure. The scheme for representing structured data is based on the Lisp cons cell. Run-time generated lists …

A Microsequenced Prolog Inference Engine, Jeffrey J. Ferguson

Retrospective Theses and Dissertations

Prolog is a symbolic logic language presently emerging among numerous expert system designs. The architecture for a microsequenced Prolog machine (UPM) capable of providing the basic language features to a host computer is proposed. The Prolog machine functions are portioned into three processor components – Input/Output, Memory, and Central (CPU), where the design of the Central Processor is emphasized. Detailed discussion outlines the CPU facilities used to implement the forward-chaining and backtracking functions for the UPM. The UPM features are compared to the PLM-1, a microsequenced Prolog inference engine under development at University of California, Berkley. An emulation of the …

Investigation Of Electronic Holography Using Spice Computer Simulation Experiments, Monish Ranjan Chatterjee

Electrical and Computer Engineering Faculty Publications

Using SPICE experiments, it has been possible to verify most of the important aspects of electronic holography. The generation and properties of dynamic echoes under different types of nonlinearities have been extensively tested, and some new information has been garnered in the process. The case of pulse and generalized memory echoes has also been tested, and the results have been fairly satisfactory. Most of all, the simplicity with which the intriguing concept of memory echoes has translated into the circuit implementation on SPICE, and the closeness of the results to predicted behavior have been somewhat of a pleasant surprise.

Since …

An Investigation To Improve Linear Predictive Vocoder Pulse/Noise Excitation Models, Elizabeth Annella Martina Effer

Electrical & Computer Engineering Theses & Dissertations

The quality of synthetic speech from Linear Predictive (LP) vocoders is known to be degraded due to the lack of detail in the commonly used pulse/noise excitation model. In this investigation, it was hypothesized that this degradation is due to the lack of precise timing information in the pulses and to the constraint that each short-time segment of excitation be either an impulse train or white noise. Accordingly, more complex excitation models were implemented using precise timing from peaks in the residual and a mixture of pulses and noise. Since the LP residual is known to be the perfect excitation …

An Inventory Of Maine's Telecommunications System, Maine State Planning Office

Maine Collection

An Inventory of Maine's Telecommunications System

Prepared for the Maine State Planning Office by Joseph M. Chaisson and Valerie Lamont of the Telecommunications Research Program at Westbrook College in Portland, Maine. July, 1985.

"The Primary purpose of this report is to provide information for Governor Brennan's Task Force on Telecommunications. The inventory also can be widely used as a reference by persons and organizations concerned with providing telecommunications services in Maine."

Contents: Introduction / Local Telephone Service / Mobile Telephone Service / Digital Termination Service / Cable Television / Paging Systems / Intra-State (Intra-LATA) Public Services / Intra-State (Intra-LATA) Private …

The Mean Return Time To A State For A Markov Chain Representing In Telephone Conversations, M Luhanga

Tanzania Journal of Engineering and Technology (TJET)

The mean return time to a state for a Markov chain representing N off-hook telephone conversations can be obtained by using ergodic flow rates [1] or renewal theory [2]. In this paper it is shown that the same result may be obtained by using no more knowledge of stochastic processes than the solution of time-homogeneous Chapman-Kolmogorov equations.

Simple Graphic Routines Ease Drawing Of Artwork For The Fabrication Of Microstrip Lines, H Mgombelo

Tanzania Journal of Engineering and Technology (TJET)

A method which uses simple graphic routines available to general computer users for drawing diagrams intended to be reproduced on printed circuit boards (PCB's) is presented. Experimental verifications for the created microchip lines are reported.

Engineer Education: Disciplinary Preferences In The Faculty Of Engineering University Of Dar Es Salaam, S Mosha

Tanzania Journal of Engineering and Technology (TJET)

Most practising engineers can hardly recall the days they had to make up their minds on whether engineering was their chosen career. This decision may have been approached with ignorance and very high expectations. Later after registering in a Faculty of Engineering the freshman was given a chance to choose a department; sometimes this had already been done for him by his sponsors so all he had to do was to walk into the preselected department.

A generation later, University entrants are faced with a similar predicament. This paper high-lights the procedures involved and proceeds to recommend the necessary fundamental …

Design Of Infrasound-Detection System Via Adaptive Lmstde Algorithm, Camille S. Khalaf

Electrical & Computer Engineering Theses & Dissertations

A proposed solution to an aviation safety problem is based on passive detection of turbulent weather phenomena through their infrasonic emission. This thesis describes a system design that is adequate for detection and bearing evaluation of infrasounds. An array of four sensors, with the appropriate hardware, is used for the detection part. Bearing evaluation is based on estimates of time delays between sensor outputs. The generalized cross correlation (GCC), as the conventional time-delay estimation (TOE) method, is first reviewed. An adaptive TUt approach, using the least mean square (LMS) algorithm, is then discussed. A comparison between the two techniques is …

Self‐Refraction Of Nonlinear Capillary‐Gravity Waves, Partha P. Banerjee, Adrianus Korpel, Karl E. Lonngren

Electrical and Computer Engineering Faculty Publications

Self‐refraction effects have been observed during the propagation of deep‐water capillary‐gravity waves. The observations are shown to be in qualitative agreement with the theory of self‐focusing and defocusing in a cubically nonlinear medium in the presence of diffraction.

Subharmonic Generation By Resonant Three‐Wave Interaction Of Deep‐Water Capillary Waves, Partha P. Banerjee, Adrianus Korpel

Electrical and Computer Engineering Faculty Publications

Subharmonic generation has been observed during the propagation of deep‐water capillary waves. The observations are shown to be in agreement with the theory of degenerate resonant noncollinear three‐wave interaction in a nonlinear, dispersive medium.

A Critical Study Of Nonlinear Echo Phenomena, Monish Ranjan Chatterjee

Electrical and Computer Engineering Faculty Publications

The present thesis attempts to give a concise and critical account of the evolution of the echo phenomena over the last thirty years. Starting with spin and photon echoes, which were among the earliest to be observed and studied, the thesis explores the experimental findings and the models proposed in connection with the more contemporary echo experiments, viz. those involving electroacoustic or polarization echoes in single and polycrystalline piezoelectric materials and in powders. Although the investigations regarding the various mechanisms of short and long term echo formation are by no means complete, a coherent picture is beginning to emerge as …

Performance Theorems For The Resource Scheduling Functions Of A Multiprocessing System, George Arthur Nicol

Dissertations and Theses

In this dissertation, a multiprocess scheduling model is developed and a set of performance theorems is constructed for the set of scheduling functions associated with the model. Each theorem describes the conditions under which a scheduling function exhibits a particular type of performance.