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Theses and Dissertations

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The Calibration Of Bistatic Radar Cross Section Measurements, Christopher J. Bradley Mar 2001

The Calibration Of Bistatic Radar Cross Section Measurements, Christopher J. Bradley

Theses and Dissertations

Recent advances in signal processing and remote sensing have highlighted the importance of bistatic radar systems for the purposes of environmental monitoring, surveillance, and tracking radar. The calibration of such systems has been problematic-much more so than similar monostatic systems, primarily as a result of the lack of reference objects suitable for calibrating at any given bistatic angle. This research deals with the problems of calibrating full-polarimetric laboratory-environment bistatic radar systems, including the lack of suitable calibration targets and procedures, and operational considerations such as alignment and mounting. Several popular bistatic calibration techniques are classified, evaluated, and comparisons are made …

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Estimation Of Relative Satellite Formation Elements In Near Circular Orbits, Ralph E. Bordner Iii Mar 2001

Estimation Of Relative Satellite Formation Elements In Near Circular Orbits, Ralph E. Bordner Iii

Theses and Dissertations

Precise relative position determination of satellite formation elements in near circular orbits is the focus of this thesis. A Bayes filter is used for the estimator with the dynamics solution obtained by solving the time periodic, linearized system via Floquet theory. This approach is similar to that of the traditional Clohessy-Wiltshire treatment, however much more of the system's behavior is retained by using a linear, time periodic system. The dynamics model includes all zonal harmonics of the Earth as well as sectoral, tesseral, and air drag perturbations. The filter algorithm was fed three types of simulated measurements: relative Carrier-Phases Differential …

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A Semantic Interface To Scenario Component Reuse In Dod Simulation Systems, Lawrence A. Breighner Mar 2001

A Semantic Interface To Scenario Component Reuse In Dod Simulation Systems, Lawrence A. Breighner

Theses and Dissertations

The Department of Defense utilizes various simulation systems to model employment of forces and weapons systems in operational environments. The data files that model these environments and weapons systems are extremely large and complex, and require many person-hours to develop. Compounding the problem, these data files are distributed across multiple systems in a heterogeneous environment. Currently, there is no automated means of identifying and retrieving reusable portions of these files for reuse in a new scenario under development. This work develops a multi-agent system that catalogs the files, and provides the user with a means of identifying and retrieving reusable …

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Development Of A Decision Framework For Knowledge Management Projects, William D. Bower Mar 2001

Development Of A Decision Framework For Knowledge Management Projects, William D. Bower

Theses and Dissertations

Air Force resources are being committed to fund, implement, and support organizational knowledge management initiatives without any overarching Air Force Knowledge Vision or Knowledge Strategy to guide these efforts. The purpose of this research is to provide a framework model and framework implementation process that can be used to guide the identification, selection, and eventual implementation of Air Force knowledge management projects. An initial Literature Review was conducted and the findings were used to develop a framework model to guide the identification and selection of appropriate knowledge management initiatives that are consistent with organizational strategy and strategic objectives. Next, a …

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Factors Influencing Air Force Members' Tolerance Of Fraternization, Amanda G. Brandau Mar 2001

Factors Influencing Air Force Members' Tolerance Of Fraternization, Amanda G. Brandau

Theses and Dissertations

AFI 36-2909, provides the current policy on acceptable and unacceptable social interactions between Air Force members. The intent of distinguishing relationships as professional or unprofessional is to preserve proper respect for authority and maintain focus on the mission through professional relationships while avoiding the negative effects of unprofessional relationships. Fraternization is one unacceptable type, which governs relationships between officers and enlisted members. There have long been differences between official policy and actual practice in the area of fraternization. These differences likely influence the acceptance of existing policy, and the amount of tolerance toward behaviors that Air Force policy would consider …

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Using Gps As A Reference System To Hit A Moving Target, Daryl J. Burnette Mar 2001

Using Gps As A Reference System To Hit A Moving Target, Daryl J. Burnette

Theses and Dissertations

The Affordable Moving Surface Target Engagement (AMSTE) project attempts to develop affordable solutions to the precise moving target surface target engagement problem. Up to this point, most of the error analysis performed for the AMSTE project has been at the error variance level, generating root-sum-square (RSS) total errors from error budgets consisting of constant error variances. In reality, the level of error for both Global Positioning System (GPS) positioning and radar targeting systems is highly dependent upon the given situation (such as the distance between sensor and target, the altitude differences, etc.) This research generates a more comprehensive model of …

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Optical And Etching Studies Of Native Aluminum Oxide Layers For Use In Microcavity Photonic Devices, William L. Bernhard Mar 2001

Optical And Etching Studies Of Native Aluminum Oxide Layers For Use In Microcavity Photonic Devices, William L. Bernhard

Theses and Dissertations

Optical communication and computing systems are required to meet future information transfer and processing needs. Microcavity devices serve as an enabling technology to implement and integrate optoelectronic systems. It is important to understand the optical and mechanical properties of materials utilize within microcavity devices. Only then is it possible to accurately model and analyze structures. Microcavity structures incorporating a high aluminum content AlGaAs layers are designed, grown, processed, and measured. The processing of these devices includes the conversion of high aluminum-content AlGaAs layers to native aluminum oxide (AlO) layers through the process of thermal oxidation. This selective conversion of microcavity …

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Effects Of Alternative Performance Criteria Upon Composition Of Air Transportable Spare Parts Kits, Murat V. Buyukacar Mar 2001

Effects Of Alternative Performance Criteria Upon Composition Of Air Transportable Spare Parts Kits, Murat V. Buyukacar

Theses and Dissertations

Airlift capacity is a definitive factor in the success of large-scale military operations. History proves that the demand for airlift soon exceeds its capacity during simultaneous deployment of forces. Therefore good solutions to the airlift capacity problem are important. This thesis contributes to the resolution of this problem by seeking ways to reduce readiness spare parts packages (RSPs) deployed for Air Force squadrons through addition of airlift criteria into the RSP selection process. We find that item cost, weight, and volume are three important criteria for RSP computations. We then offer a method for implementing these three criteria in the …

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Analysis And Evaluation Of The Macroscopic Organizational Structure Of Red Horse, Lance D. Clark Mar 2001

Analysis And Evaluation Of The Macroscopic Organizational Structure Of Red Horse, Lance D. Clark

Theses and Dissertations

The primary contingency engineering capability within the United States Air Force is provided by Rapid Engineer Deployable, Heavy Operations Readiness Squadron, Engineer (RED HORSE). This thesis examines the macroscopic organizational structure of RED HORSE; that is, the manner in which RED HORSE resources (personnel and equipment) are organized collectively, above the unit (squadron or flight) level. It builds on the findings of the Air Combat Command - sponsored RED HORSE 2010 Strategic Study, and focuses on issues of geographic location and chain of command above the unit level, as the study found these two topics were found to be vital …

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A Quantitative Decision Support Model To Aid Selection Of Combat Aircraft Force Mixes For Contingency Deployment, Paul G. Filcek Mar 2001

A Quantitative Decision Support Model To Aid Selection Of Combat Aircraft Force Mixes For Contingency Deployment, Paul G. Filcek

Theses and Dissertations

Selection of combat aircraft during crisis action planning can be of critical importance. In determining the value of force mixes, it is proposed that one can evaluate extrinsic and intrinsic value separately. Intrinsic value is the designed capability of a weapons platform to accomplish a specified aerospace mission. Extrinsic value is the expected appropriateness of such platforms, given the environmental characteristics in which they must operate. This research develops a decision support tool for planners in determining the extrinsic value of force mixes, which then expedites the selection of best overall force mixes. The research included: content analysis of official …

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The Effect Of External Safeguards On Human-Information System Trust In An Information Warfare Environment, Gregory S. Fields Mar 2001

The Effect Of External Safeguards On Human-Information System Trust In An Information Warfare Environment, Gregory S. Fields

Theses and Dissertations

This research looks at how human trust in an information system is influenced by external safeguards in an Information Warfare (1W) domain. Information systems are relied upon in command and control environments to provide fast and reliable information to the decision-makers. The degree of reliance placed in these systems by the decision-makers suggests a significant level of trust. Understanding this trust relationship and what effects it is the focus of this study. A model is proposed that predicts behavior associated with human trust in information systems. It is hypothesized that a decision-maker's belief in the effectiveness of external safeguards will …

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A Flexible Framework For Collaborative Visualization Applications Using Java Spaces, Sean C. Butler Mar 2001

A Flexible Framework For Collaborative Visualization Applications Using Java Spaces, Sean C. Butler

Theses and Dissertations

The complexity of modern tasks is rising along with the level of technology. Two techniques commonly used to deal with complexity are collaboration and information visualization. Recently, computer networks have arisen as a powerful means of collaboration, and many new technologies are being developed to better utilize them. Among the newer, more promising of these technologies is Sun Microsystems' JavaSpaces ™, a high-level network programming API. This thesis describes a tool for developing collaborative visualization software using JavaSpaces-an application framework and accompanying toolkit. In addition to a detailed description of the framework, the thesis also describes an application implemented using …

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Predicting Software Development Cost For Command And Control Systems, Anthony W. Fife Mar 2001

Predicting Software Development Cost For Command And Control Systems, Anthony W. Fife

Theses and Dissertations

In the past, the Department of Defense (DoD) has relied upon commercial software estimating tools. However, these tools are somewhat unreliable when it comes to estimating military systems, particularly Command and Control Systems. The purpose of this study was to develop a parametric model using linear regression to estimate software development costs for DoD Command and Control systems. The developed model is unique in a few ways. First, the model is derived from Department of Defense command and control data. Second, while traditional models require volumes of variables to create estimates, the developed model only requires a few key variables …

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Numerical Study Of Optical Delay In Semiconductor Multilayer Distributed Bragg Reflector And Tunable Microcavity Structures, Michael I. K. Etan Mar 2001

Numerical Study Of Optical Delay In Semiconductor Multilayer Distributed Bragg Reflector And Tunable Microcavity Structures, Michael I. K. Etan

Theses and Dissertations

The Air Force has a growing need for the greater bandwidth, speed, and flexibility offered by optical communication links. Future space systems and airborne platforms will most likely use optical signals for efficient power transmission and to minimize the possibility of spoofing and eavesdropping. Tunable optical delays play an important role in the implementation of free space optical communication links. The primary challenge in implementing these systems is the active maintenance of coherent wave fronts across the system's optical aperture. For space applications, this aperture may he hundreds of meters in diameter. Spatial segmentation of a large aperture into smaller …

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United States Air Force Graduate Degrees From 1990 To 2000: A Comparison, Jonathan G. Downing Mar 2001

United States Air Force Graduate Degrees From 1990 To 2000: A Comparison, Jonathan G. Downing

Theses and Dissertations

Throughout its history, the United States Air Force has been concerned with technical graduate education. In 1947, the Ridenour Report stated the importance and need of Air Force officers with technical graduate degrees. This emphasis has served the Air Force well, but there is concern among senior Air Force leaders that there has been an erosion of these technical skills and graduate education. This research will examine the issues surrounding technical graduate education in the Air Force and will address the possible loss of such technical education. The results of this research provide specific statistical data and analysis on the …

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An Investigation Of The Contracting Officer Career Pyramid, William B. Elyea Mar 2001

An Investigation Of The Contracting Officer Career Pyramid, William B. Elyea

Theses and Dissertations

Air Force contracting officers rely on published guidance to assist in establishing their career objectives. This thesis uses empirical data to evaluate the published Air Force career guidance. The data set is comprised of complete duty histories from all active duty colonels, colonel selects, and general officers in the contracting career field. The guidance implies a career path to an exceptional career but provides no empirical validation. This thesis follows a rigorous procedure to objectively evaluate the Air Force guidance. The guidance is translated into 18 research questions based on its main tenets. Each duty occurrence is categorized by type …

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Electronic Quenching Of The A(0+U) State Of Bi2, Joseph L. Cox Mar 2001

Electronic Quenching Of The A(0+U) State Of Bi2, Joseph L. Cox

Theses and Dissertations

Temporally-resolved laser induced fluorescence ofhigh vibrational levels in Bi2 A(0+u) above and below the predissociation limit of v'=22 were investigated by observing total fluorescence from a wavelength tunable, pulsed dye laser. Electronic quenching ofBi2 A(0+u) by five collision partners (Ne, Ar, Kr, Xe, N2) was examined for four vibrational levels (v'=22,23,24,25). Electronic quenching by a sixth collision partner (He) was examined for eight vibrational levels (v'=18 through 25). The quenching from stable vibrational levels (v'≤22) was independent ofvibrational quantum number. A significant increase in quenching occurs for the predissociated level …

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Influence Of Feedback And Comment Labels On Information Sharing In A Computer Mediated Collaborative Environment, Gary D. Denney Mar 2001

Influence Of Feedback And Comment Labels On Information Sharing In A Computer Mediated Collaborative Environment, Gary D. Denney

Theses and Dissertations

A group support system (GSS) uses a combination of networked personal computers, software, and human facilitation to improve the group decision-making process. Group support Systems are being used in the Air Force today in a variety of capacities and in particular by the Warner-Robins Air Logistics Center (WR-ALC) to assess acquisition risks. Prior GSS research has found that certain structural and social dimensions of GSS designs might influence whether optimal process improvements take place. However, the dimensions that positively influence group performance have continued to be a matter of debate. This thesis looked at several structural and social contingencies to …

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Routing Unmanned Aerial Vehicles While Considering General Restricted Operating Zones, Darin T. Brown Mar 2001

Routing Unmanned Aerial Vehicles While Considering General Restricted Operating Zones, Darin T. Brown

Theses and Dissertations

U.S. military forces employ unmanned aerial vehicles (UAVs) to conduct intelligence-gathering missions worldwide. For a typical mission, commanders may task UAV operators to gather imagery on 100 or more sites or targets. UAV operators must quickly prepare mission plans that meet the needs of their commanders while dealing with real-world constraints such as time windows, site priorities, imagery requirements, UAVs with different capabilities (i.e. imagery equipment, speed, and range), and UAVs departing from different bases. Previous AFIT research provided the UAV Battlelab with a tool, AFIT Router, for generating high-quality routes to aid mission planning. This research enhances the AFIT …

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Optimization Of Palladium-Catalyzed In Situ Destruction Of Trichloroethylene-Contaminated Groundwater Using A Genetic Algorithm, Manuel Fernandez Mar 2001

Optimization Of Palladium-Catalyzed In Situ Destruction Of Trichloroethylene-Contaminated Groundwater Using A Genetic Algorithm, Manuel Fernandez

Theses and Dissertations

Conventional technologies for the treatment of groundwater contaminated with chlorinated solvents have limitations that have motivated development of innovative technologies. One such technology currently under development involves using palladium-on-alumina (Pd/Al) as a catalyst to promote dechlorination. Pd/Al catalyst may be used in-well as part of a re-circulating horizontal flow treatment well (HFTW) system. An HFTW system involves two or more dual-screened wells, with in-well reactors, to capture and treat contaminated groundwater without the need to pump the water to the surface. In this study, objective and fitness functions, based on system costs and TCE concentration requirements, were developed to optimize …

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Atmospheric Conditions Associated With Lightning During Snow And Ice Events, Randall J. Haeberle Mar 2001

Atmospheric Conditions Associated With Lightning During Snow And Ice Events, Randall J. Haeberle

Theses and Dissertations

The purpose of this research was to find the atmospheric mechanisms associated with lightning in snow and ice events. The specific mechanisms that were examined were low-level wind shear, upper level divergence, surface temperature, low-level temperature, the -10 ° C level, and precipitable water. A chi-squared dependency test showed the strong association of low-level wind shear to each precipitation type (snow, sleet/freezing rain, rain) in two separate studies. Surface temperature appeared to have a relationship to lightning in all precipitation categories, while no significant relationship to lightning in all precipitation categories, while no significant relationship was found with upper level …

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Estimating Deployed Airlift And Equipment Requirements For F-16 Aircraft In Support Of The Advanced Logistics Project, Matthew W. Goddard Mar 2001

Estimating Deployed Airlift And Equipment Requirements For F-16 Aircraft In Support Of The Advanced Logistics Project, Matthew W. Goddard

Theses and Dissertations

The Advanced Logistics Project (ALP) is a 5-year DARPA effort to investigate automated architectures to increase the efficiency of logistics support for deploying combat forces. The Mission-Resource Value Assessment Tool (M-R VAT) is a joint AFIT/AFRL adjunct processor to the ALP. The purpose of the M-R VAT is to select optimal force packages to meet the needs of theater commanders. This research supports the development of the M-R VAT's capability through the development of an airlift estimation function and validating equipment requirement rule-sets. This airlift estimation function will allow the M-R VAT optimization algorithms to constrain the selection of the …

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An Analysis Of The Interaction Between The J3 And J4 War Planning Staffs During The Phases Of Crisis Action Planning, Michael J. Colvard Mar 2001

An Analysis Of The Interaction Between The J3 And J4 War Planning Staffs During The Phases Of Crisis Action Planning, Michael J. Colvard

Theses and Dissertations

A principal operational concept of Joint Vision 2020 is that of Focused Logistics, which promotes a merger of information and logistics technologies. The Defense Advanced Research Projects Agency's Advanced Logistics Project (ALP) supports this concept of Focused Logistics and seeks to leverage information technologies to obtain control over the logistics pipeline. The current campaign planning process is limited by the information made available to the decision-makers. In order for ALP to assist the decision-maker in selecting a single optimal deployment plan, the founding assumptions of alternatives considered must be valid. Logistical issues are major constraints in the war planning process. …

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An Analysis Of The Acquisition Process For Simplified Acquisition Of Base Engineering Requirements (Saber) Contracts And Its Potential Impact On Contractor Performance, Brian J. Heaps Mar 2001

An Analysis Of The Acquisition Process For Simplified Acquisition Of Base Engineering Requirements (Saber) Contracts And Its Potential Impact On Contractor Performance, Brian J. Heaps

Theses and Dissertations

The Simplified Acquisition of Base Engineering Requirements (SABER) contract's main purpose is to expedite contract award of civil engineer requirements through the issuance of individual delivery orders. The contract contains a collection of detailed task specifications that include most types of real property maintenance, repair, and construction work. The Assistant Secretary of the Air Force for Acquisition's Operational Contracting Division (SAF/AQCO) identified a number of failed SABER contracts. The problem statement designed for this research effort was: There are a large number of SABER contractors that are failing during the performance period on their SABER contracts. SAF/AQCO is trying to …

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Validation And Assessment Of Dmsp Electron Temperatures In The Topside Ionosphere, Bradford S. Green Mar 2001

Validation And Assessment Of Dmsp Electron Temperatures In The Topside Ionosphere, Bradford S. Green

Theses and Dissertations

Geomagnetic disturbances in the near earth space environment can adversely affect numerous military and Department of Defense (DoD) systems and operations. To improve the prediction accuracy of such disturbances, the next generation of space environment forecast models aims to automatically ingest real-time ionospheric measurements. This research validates and assesses one such measurement - the Defense Military Satellite Program (DMSP) measured electron temperature (Te). DMSP Te data were validated against near simultaneous incoherent scatter radar (ISR) Te measurements from Millstone Hill, MA and Sondrestrom, Greenland between Winter 1996 and Summer 2000. Of the 37 Millstone and six …

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Cooperative Behavior Schemes For Improving The Effectiveness Of Autonomous Wide Area Search Munitions, Daniel P. Gillen Mar 2001

Cooperative Behavior Schemes For Improving The Effectiveness Of Autonomous Wide Area Search Munitions, Daniel P. Gillen

Theses and Dissertations

The problem being addressed is how to best find and engage an unknown number of targets in unknown locations using multiple autonomous wide area search munitions. In this research cooperative behavior is being investigated to improve the overall mission effectiveness. A simulation was used to emulate the behavior of autonomous wide area search munitions and measure their overall expected performance. This code was modified to incorporate the capability for cooperative engagement based on a parameterized decision rule. Using Design of Experiments and Response Surface Methodologies, the simulation was run to achieve optimal decision rule parameters for given scenarios and to …

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Modeling Pressurized Water Reactor Kinetics, William H. Harman Mar 2001

Modeling Pressurized Water Reactor Kinetics, William H. Harman

Theses and Dissertations

A computer model of a pressurized water reactor (PWR) was developed for use as a teaching tool in graduate level nuclear reactor courses. The development, based on the diffusion equation, includes the methodology for solving the steady state spatial dependence of the neutron power output in a homogeneous right circular cylinder unreflected PWR system. This includes a two dimensional one energy group model, a three dimensional one energy group model, and a three dimensional two energy group model. To solve the homogeneous diffusion equation, a method was developed to search for criticality of the reactor based on the geometry and …

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Aircrew Ionizing Doses From Nuclear Weapon Bursts, Fred E. Garcia Ii Mar 2001

Aircrew Ionizing Doses From Nuclear Weapon Bursts, Fred E. Garcia Ii

Theses and Dissertations

Total radioactive doses to aircrew members have been calculated in the past using different methods. The methodologies include smearing models, disk-tosser codes, and puff models. This study uses output data from the Hazard Prediction and Assessment Capability (HPAC) code as input into a FORTRAN program written by the author to calculate total dose to aircrew members through sky-shine and cabin ingestion. A description of the input parameters and new project setup in the Nuclear Weapon (NWPN) module within HPAC is given. The various aspects of controlling the project and plotting the data are also described. This information is presented essentially …

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A Low Power Application-Specific Integrated Circuit (Asic) Implementation Of Wavelet Transform/Inverse Transform, Daniel N. Harvala Mar 2001

A Low Power Application-Specific Integrated Circuit (Asic) Implementation Of Wavelet Transform/Inverse Transform, Daniel N. Harvala

Theses and Dissertations

A unique ASIC was designed implementing the Haar Wavelet transform for image compression/decompression. ASIC operations include performing the Haar wavelet transform on a 512 by 512 square pixel image, preparing the image for transmission by quantizing and thresholding the transformed data, and performing the inverse Haar wavelet transform, returning the original image with only minor degradation. The ASIC is based on an existing four-chip FPGA implementation. Implementing the design using a dedicated ASIC enhances the speed, decreases chip count to a single die, and uses significantly less power compared to the FPGA implementation. A reduction of RAM accesses was realized …

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Control And Characterization Of Line-Addressable Micromirror Arrays, Harris J. Hall Mar 2001

Control And Characterization Of Line-Addressable Micromirror Arrays, Harris J. Hall

Theses and Dissertations

This research involved the design and implementation of a complete line-addressable control system for a 32x32 electrostatic piston-actuated micromirror array device. Line addressing reduces the number of control lines from N2 to 2N making it possible to design larger arrays and arrays with smaller element sizes. The system utilizes the electromechanical bi-stability of individual elements to bold arbitrary bi-stable phase patterns. The control system applies pulse width modulated (PWM) signals to the rows and columns of the micromirror array. Three modes of operation were conceived and built into the system. The first was the traditional signal scheme which requires …

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