Electrical and Computer Engineering Commons^™

Synthetic Aperture Radar Imaging Simulated In Matlab, Matthew Schlutz

Master's Theses

This thesis further develops a method from ongoing thesis projects with the goal of generating images using synthetic aperture radar (SAR) simulations coded in MATLAB. The project is supervised by Dr. John Saghri and sponsored by Raytheon Space and Airborne Systems. SAR is a type of imaging radar in which the relative movement of the antenna with respect to the target is utilized. Through the simultaneous processing of the radar reflections over the movement of the antenna via the range Doppler algorithm (RDA), the superior resolution of a theoretical wider antenna, termed synthetic aperture, is obtained. The long term goal …

Harmonic Analysis Of A Static Var Compensated Mixed Load System, James David Ruckdaschel

Master's Theses

As power electronic based controllers and loads become more prevalent in power systems, there is a growing concern about how the harmonics generated by these controllers and loads affect the power quality of the system. One widely used power electronic based load is the Variable Frequency Drive (VFDs) used to vary the speed of an induction motor; whereas a common example of a power electronic based controller used in power systems is the Static VAR Compensator (SVC) for improving a system’s power factor. In this thesis, the harmonic content and overall performance of a system including both a VFD and …

Target Tracking Using Various Filters In Synthetic Aperture Radar Data And Imagery, Jessica L. Kiefer

Master's Theses

This thesis explores the use and accuracy of several discrete-time image filters for the purpose of target tracking in Synthetic Aperture Radar imagery. Both extended targets and point targets are used for tracking, showing the need for different types of filters for each target type.

Monte Carlo analysis is performed on the results of the extended target filter results to determine the absolute mean-squared error between the filter prediction of the target centroid and the actual location of the target centroid. Two different filters were chosen for the extended target: Kalman and H Infinity.

Both the Kalman and H Infinity …

Development Of An Imager System Optimized For Low-Power, Limited-Bandwidth Space Applications, Kalia R. Glassey

Master's Theses

A relatively new picosatellite standard, CubeSats have traditionally been used for simple educational missions. As CubeSats become more complex and utilize more complex sensors such as imagers, they gain enhanced credibility as satellite platforms.

Imaging systems on CubeSats have the potential to be used for a variety of uses, such as earth and weather monitoring, attitude determination, and remote sensing. However the size and power limitations of CubeSats pose an interesting challenge to the design of a capable, robust imaging system.

This thesis outlines the objectives and requirements of CP-3’s imaging system, and describes the development process and methods. Test …

Shielding Effectiveness Of Superalloy, Aluminum, And Mumetal Shielding Tapes, Cindy Suit Cheung

Master's Theses

Using MIL-HDBK-419A, MATLAB and Nomographs, Shielding Effectiveness for the Magnetic Field, Electric Field, and Plane Wave were calculated over a frequency range from 10 Hz to 1 GHz. The three shielding tapes used included superalloy, aluminum, and mumetal. Calculations for Shielding Effectiveness involve the computation of Absorption Loss, Reflection Loss, and Re-Reflection Correction Factor. From the outcome of the calculations, it was suitable to conclude that all three metals fulfill the 40 dB Shielding Effectiveness requirements for SGEMP fields for frequencies greater or equal to 1 MHz. Accordingly, all three shielding tapes provide at least 40 dB of shielding to …

Optimization Of Gan Laser Diodes Using 1d And 2d Optical Simulations, Sean Richard Keali'i Jobe

Master's Theses

This paper studies the optical properties of a GaN Laser Diode (LD). Through simulation, the GaN LD is optimized for the best optical confinement factor. It is found that there are optimal thicknesses of each layer in the diode that yield the highest optical confinement factor. There is a strong relationship between the optical confinement factor and lasing threshold—a higher optical confinement factor results in a lower lasing threshold. Increasing optical confinement improves lasing efficiency. Blue LDs are important to the future of lighting sources as they represent the final color in the RGB spectrum that does not have a …

Analysis And Design Of Continuous Input Current Multiphase Interleaved Buck Converter, Sean Michael Zich

Master's Theses

The power requirements for microprocessors have been increasing per Moore's Law. According to International Technology Roadmap (ITRS), Voltage Regulator Module (VRM) for microprocessors will be about 200 W at 1 V output in 2010. With the VRM’s topology of synchronous buck, serious technical challenges such as small duty cycle, high switching frequencies, and higher current demands, contribute to decreased power density and increased cost.

This thesis proposes a Continuous Input Current Multiphase Interleaved Buck topology to solve the technical challenges of powering future microprocessors. This new topology is aimed to improve past topologies by providing continuous input current and improved …

Three-Dimensional Target Modeling With Synthetic Aperture Radar, John R. Hupton

Master's Theses

Conventional Synthetic Aperture Radar (SAR) offers high-resolution imaging of a target region in the range and cross-range dimensions along the ground plane. Little or no data is available in the range-altitude dimension, however, and target functions and models are limited to two-dimensional images. This thesis first investigates some existing methods for the computation of target reflectivity data in the deficient elevation domain, and a new method is then proposed for three-dimensional (3-D) SAR target feature extraction.

Simulations are implemented to test the decoupled least-squares technique for high-resolution spectral estimation of target reflectivity, and the accuracy of the technique is assessed. …

Analysis And Design Of Interleaving Multiphase Dc-To-Dc Converter With Input Lc Filter, Kevin Thomas Delrosso

Master's Theses

The future of microprocessors is unknown. Over the past 40 years, their historical trend has been for adopting smaller and more powerful designs that drive the world that we live in today. The state of the microprocessor business today faces a crossroad, wishing to continue on the historical trend of doubling the number of transistors on a chip every 18 months (Moore’s Law) but also facing the realistic task of needing to power these sophisticated devices. With the low voltages and high currents that are required for these microprocessors to operate, it poses a difficult task for the future designers …

High Speed Wavelength Tuning Of Sgdbr Lasers For Optical Coherence Tomography Applications, Benjamin Maher

Master's Theses

The application of Sample Grated Distributed Bragg Reflector (SGDBR) wavelength tunable lasers for swept-wavelength Optical Coherence Tomography (OCT) is explored. OCT is a method of measuring reflectivity versus distance into samples under test with a focused infrared light source. Swept wavelength OCT requires a laser light source that is capable of sweeping its wavelength quickly over the entire wavelength range of the tunable laser. Fast sweeping of the laser's wavelength enables real-time imaging of a wide surface area of the surface under test. This thesis will show that SGDBR lasers can be designed to meet the fast wavelength ramp speeds …

Analysis And Design Of Multiphase Multi-Interleave Dc-Dc Converter With Input-Output Bypass Capacitor, Furqan Mubashir Saleemi

Master's Theses

The power requirements for the microprocessor have been increasing as per Moore's Law. According to International Technology Roadmap (ITRS), the Voltage Regulator Module (VRM) for the microprocessor will be 200 W(with 1V, 200A output) in 2010. With the VRMs topology of synchronous buck, serious technical challenges such as small duty cycle, high switching frequencies, and higher current demands, contribute to decreased power density and increased cost. This thesis proposes a Multiphase Multi-Interleave Buck topology to solve the technical challenges of powering future microprocessors. The critical design parameter values are selected using the theoretical design equations and calculations. The design is …

Theory, Simulation, Fabrication And Testing Of Double Negative And Epsilon Near Zero Metamaterials For Microwave Applications, Neil Patel

Master's Theses

Natural structures exhibiting simultaneous negative bulk permittivity and permeability have not yet been discovered. However, research interest over the past five years has grown with the proposition that artificial structures exhibiting these properties are realizable using specially-designed metallic inclusions embedded in host dielectric bodies. A periodic structure of metallic inclusions much smaller than the guided wavelength and embedded in a host dielectric medium is known in the physics and microwave communities as a "metamaterial". Such frequency-dependent effectively homogeneous materials may be designed to exhibit negative permeability and permittivity at certain frequencies. As predicted by electromagnetic theory, such negative index or …