Engineering Commons^™

Aln Contour-Mode Resonators For Narrow-Band Filters Above 3 Ghz, Matteo Rinaldi, Chiara Zuniga, Chengjie Zuo, Gianluca Piazza

Matteo Rinaldi

This paper reports on the design and experimental verification of a new class of thin-film (250 nm) Super High Frequency (SHF) laterally-vibrating piezoelectric microelectromechanical (MEMS) resonators suitable for the fabrication of narrow-band MEMS filters operating at frequencies above 3 GHz. The device dimensions have been opportunely scaled both in the lateral and vertical dimensions in order to excite a contour-extensional mode of vibration in nano features of an ultra-thin (250 nm) Aluminum Nitride (AlN) film. In this first demonstration two-port resonators vibrating up to 4.5 GHz were fabricated on the same die and attained electromechanical coupling, kt2, in excess of …

Characterization Of Hardening By Design Techniques On Commercial, Small Feature Sized Field-Programmable Gate Arrays, Thomas E. Simmons

Theses and Dissertations

In this thesis, a methodology is developed to experimentally test and evaluate a programmable logic device unde r gamma irradiation. The purpose of which is to determine the radiation effects and characterize the improvements of various hardening by design techniques. The techniques analyzed in this thesis include Error Correction Coding (ECC) and Triple Modular Redundancy (TMR). The TMR circuit includes three different functional implementations of adders compared to TMR voted circuits of those same adders. The TMR is implemented with the same functional adders and as a Functional TMR (FTMR) with three different function adders that are voted on. The …

Full-Wave Based Validation Of Stripline Field Applicator For Low Frequency Material Measurements, James H. Crane Ii

Theses and Dissertations

This research presents the analysis and verification of a stripline designed by Air Force Research Laboratory for use in measuring the electrical properties of materials at low frequencies and high temperature. It is designed to operate in the TEM mode up to 4 Ghz and have a characteristic impedance of 50 ohms. A full wave base method is used to analyze the structure. The parallel plate waveguide dyadic Green's function is developed for a current immersed in a PEC parallel plate environment. It is used to formulate a pair of coupled electric field integral equations (CIE). These CIEs are solved …

Implementation Of Collaborative Rf Localization Using A Software-Defined Radio Network, Augustine A. Honore

Theses and Dissertations

This thesis investigates the use of collaboration between sensor nodes that were tasked with localizing a radio frequency emitter. Localization is a necessary component for dynamic spectrum access. Using a set of software-defined radios as our sensors and a received signal strength-based maximum likelihood localization algorithm, we successfully localized transmitting nodes based on their received signal strength. Our experiment was conducted outdoors using a flexible topology that could be shaped into 21 sub-topologies that varied in size, and orientation with respect to the transmitters. This was made possible through application of a time shift concept and a post-processing technique. We …

Using Shadows To Detect Targets In Synthetic Aperture Radar Imagery, Brian P. Donnell

Theses and Dissertations

Synthetic Aperture Radar (SAR) can generate high resolution imagery of re- mote scenes by combining the phase information of multiple radar pulses along a given path. SAR based Intelligence, Surveillance, and Reconnaissance (ISR) has the advantage over optical ISR that it can provide usable imagery in adverse weather or nighttime conditions. Certain radar frequencies can even result in foliage or limited soil penetration, enabling imagery to be created of objects of interest that would otherwise be hidden from optical surveillance systems. This thesis demonstrates the capability of locating stationary targets of interest based on the locations of their shadows and …

Surface Acoustic Wave Devices As Chemical Vapor Sensors, Daniel Gallagher

Theses and Dissertations

In order to effectively neutralize non-traditional threats to US forces and population such as improvised explosive devices (IED) and chemical, biological, radio- logical, nuclear, and explosive (CBNRE) weapons, a flexible vapor sensor platform is proposed. This work involves the design, fabrication, and testing of coated surface acoustic wave devices for vapor sensing ability. Devices were fabricated in-house using MEMS fabrication techniques, then coated with a thin layer of a Nafion polymer. The frequency response of coated devices displayed 2 MHz frequency shifts around the resonance frequency upon introduction of ethanol vapors into the nitrogen vapor stream. This indicates strong sensing …

Electron Multipactor: Theory Review, Comparison And Modeling Of Mitigation Techniques In Icepic, Neil G. Rogers

Theses and Dissertations

Mitigation approaches for single surface multipactor at dielectric windows are investigated using Particle-In-Cell (PIC) simulations. Initially baseline susceptibility diagrams are constructed analytically and compared with self-consistent, dynamic system trajectories. The power deposited on the surface of a dielectric window in an HPM system is considered using three different methods and the results of PIC simulations. Geometric mitigation is then considered by varying the window orientation with respect to the HPM electric held. Small angular deviations, less than 20 degrees, from the nominal case of normal incidence show dramatic changes in the susceptibility diagram. A materials approach to mitigation is then …

Electric Energy Sector In Egypt: A Review, Dr. Adel A. Elbaset

Dr. Adel A. Elbaset

No abstract provided.

A Novel Discrete Dimming Ballast For Linear Fluorescent Lamps, Haiyan Wang, Ana Vladan Stankovic, Louis Nerone, David Kachmarik

Electrical and Computer Engineering Faculty Publications

A novel discrete dimming ballast for linear fluorescent lamps is proposed in this paper. A proposed dimming control circuit is combined with a ballast module for multiple lamps to realize control of three discrete lighting levels. Compared with conventional step dimming or ON-OFF control methods, the proposed discrete dimming method has the following advantages: 1) digital signal is generated by the dimming control circuit to control the lamps' turn- ON and -OFF, which makes the system more reliable and integrated; 2) the proposed discrete dimming system replaces relays, which are necessary in conventional lamp ON-OFF control, and therefore decreases the …

Deep Levels In Gate And Gate:In Crystals Investigated By Deep-Level Transient Spectroscopy And Photoluminescence, Y. Cui, D. D. Caudel, P. Bhattacharya, A. Burger, K. C. Mandal, D. Johnstone, S. A. Payne

Faculty Publications

No abstract provided.

A Mems Multi-Cantilever Variable Capacitor On Metamaterial, Luke A. Rederus

Theses and Dissertations

Negative refractive index materials are an example of metamaterials that are becoming increasingly popular. Research into these metamaterials could possibly be the first steps toward bending electromagnetic radiation (i.e., microwaves, light, etc.) around an object or person. Split ring resonators (SRR) are classified as metamaterials that create an artificial magnetic response from materials with no inherent magnetic properties. Once fabricated, an SRR has a specific resonant frequency due to its permanent geometry. This research introduces a new concept of using a variable capacitive micro- electro-mechanical system (MEMS) device located at the gap of an SRR to mechanically alter the capacitance …

Power Generation By Harvesting Ambient Energy With A Micro-Electromagnetic Generator, James H. Shields

Theses and Dissertations

This thesis investigated the potential power output of a micro-electromagnetic generator fabricated using typical microfabrication materials and techniques. The design was based on a desire to free bio-implanted or remote electronic devices from batteries and their finite power supplies. A micro-electromagnetic generator could harvest energy from the ambient environment and power such devices indefinitely. Designs for the stator coil and rotor magnet components of the generator were optimized to produce maximum current density based upon electromagnetic theory. The relative orientation of the coil to the rotor and material selection for each component were considered. Coils were fabricated using low-resistance gold. …

Gravimetric Chemical Sensor Based On The Direct Integration Of Swnts On Aln Contour-Mode Mems Resonators, Matteo Rinaldi, Chiara Zuniga, Nipun Sinha, Marzie Taheri, Samuel M. Khamis, Alan T. Johnson, Gianluca Piazza

Nipun Sinha

This paper reports on the first demonstration of a gravimetric chemical sensor based on direct integration of Single Wall Carbon Nanotubes (SWNTs) grown by Chemical Vapor Deposition (CVD) on AlN Contour-Mode MicroElectroMechanical (MEMS) resonators. In this first prototype the ability of SWNTs to readily adsorb volatile organic chemicals has been combined with the capability of AlN Contour-Mode MEMS resonator to provide for different levels of sensitivity due to separate frequencies of operation on the same die. Two devices with resonance frequencies of 287 MHz and 442 MHz have been exposed to different concentrations of DMMP in the range from 80 …

Multi-Frequency Pierce Oscillators Based On Piezoelectric Aln Contour-Mode Mems Resonators, Chengjie Zuo, Nipun Sinha, Jan Van Der Spiegel, Gianluca Piazza

Nipun Sinha

This paper reports on the first demonstration of multi-frequency (176, 222, 307, and 482 MHz) oscillators based on piezoelectric AlN contour-mode MEMS resonators. All the oscillators show phase noise values between –88 and –68 dBc/Hz at 1 kHz offset and phase noise floors as low as –160 dBc/Hz at 1 MHz offset. The same Pierce circuit design is employed to sustain oscillations at the 4 different frequencies, while the oscillator core consumes at most 10 mW. The AlN resonators are currently wirebonded to the integrated circuit realized in the AMIS 0.5 μm 5 V CMOS process. This work constitutes a …

A Novel Storage Area Network (San) Extension Solution Over Passive Optical Networks (Pons), Si Yin

Dissertations

After 9/11 and the 2003 power grid failure in North America, storage area network (SAN) extension has emerged as a critical option to ensure business continuity. However, SAN extension encounters challenges in the access network including the scalability, cost, bandwidth bottleneck, and throughput. In this dissertation, a new solution, SAN extension over passive optical networks (S-PONs), has been proposed to address the above problems. PONs are the mainstream wireline technology for upgrading the megabit-level access solutions (such as xDSL and Cable Modem) into gigabit-level broadband access. To tackle the scalability problem and cost challenge, the S-PON architecture has been designed …

Nano-Structured Platforms As A Spectroscopic Tool, Ruiqiong Li

Theses

Nano-structured platforms have been studied for the purpose of enhancing weak fluorescence signals. Each platform was constructed as a thin oxide layer on top of a metal (aluminum) The oxide was perforated with hexagonal array of nano-holes. The pitch of the array was much smaller than the optical wavelengths used. Surface charge waves (Surface Plasmons) could be excited when the platform was oriented at specific direction with respect to the incident optical beam. At this point one can demonstrate that fluorescence signals could be amplified. Since the oxide (alumina) is bio-compatible, one can envision using such platforms in the study …

Optimal Design Of Wind-Pv-Diesel-Battery System Using Genetic Algorithm, Dr. Adel A. Elbaset

Dr. Adel A. Elbaset

The optimization of diesel generators (DGs) and renewable energy sources have to be done within a cost benefit, high reliability and environmentally friendly framework. Most of optimization method just consider only from economical point of view. This paper presents complete optimization method involving of cost, reliability and pollutant emission into optimization process. The reliability level is analyzed using basic probabilistic concept in order to find loss of load probability (LOLP). This value is then used to determine the customer damage cost due to electricity interruption. Meanwhile, CO2 emission as an indicator of pollution is calculated to determine the annual emission …

Tilted Parallel Dielectric Slab As A Multilevel Attenuator For Incident P- Or S-Polarized Light, R. M.A. Azzam

Electrical Engineering Faculty Publications

Under the condition of first-order blooming, a parallel dielectric slab, which is inserted in the path of an obliquely incident p- or s-polarized light beam, introduces multiple discrete attenuation levels given by 1/3, 4/27, 4/243,...... in reflection and 4/9, 4/81, 4/729,...... in transmission. These attenuation levels are independent of the slab refractive index, incident p or s linear polarization, or the presence of identical transparent surface coatings at the front and back sides of the slab. Therefore, the tilted slab provides multidecade reflectance and attenuation reference values that can be used in calibrating spectrophotometers and filters, and also …

System Performance Of Absolute Quartz-Crystal Barometers With Sub-Microbar Precision, Ganesh Kumar Subramanian Ananthanarayanan

Masters Theses 1911 - February 2014

In this thesis, the performance of absolute quartz-crystal barometers is presented, and their ability to measure, with sub-microbar precision, atmospheric pressure fluctuations with periods as short as a few seconds is demonstrated. The first observations of ocean-generated atmospheric infrasound with periods of about 5 s and sub-microbar amplitudes, called microbaroms, using single absolute barometers are presented. These barometers can measure microbaroms with amplitudes down to 50 nanobars and the 1-h estimates of microbarom amplitudes calculated from data collected independently with three collocated barometers differed by only a few nanobars. The observed microbaroms have amplitudes between 0.2 microbars and 1 microbar …

Design And Development Of A Ka-Band Interferometer For Cryospheric Applications, Harish K. Vedantham

Masters Theses 1911 - February 2014

Topographic maps of the earth are essential to geographic and earth science studies. In particular, mapping and estimating physical parameters of the earth’s water and ice cover are critical to global climate studies. Among these, snow, ocean and fresh water topography, snow wetness and water equivalent are of immediate interest to the scientific community.

Challenges in the instrument development and deployment posed by these required measurements are twofold. Firstly, these measurements are required to have global coverage, yet maintain stringent spatial resolution and accuracy margins. Secondly, snow topography measurement requires minimal electromagnetic wave penetration through snow, hence requiring the use …

Magnetically Deflectable Mems Actuators For Optical Sensing Applications, Matthew Montgomery

Electronic Theses and Dissertations

In this work, new small deflection magnetic actuators have been proposed, designed, and tested for applications in Surface Enhanced Raman Scattering optical sensors. Despite the fact that SERS sensors have been shown to increase Raman over ten orders of magnitude for molecular detection, several technological challenges have prevented the design of practical sensors, such as making SERS sensors that can efficiently detect a wide variety of molecules. Since the optimum signal-to-noise in SERS occurs at different excitation wavelengths for different molecules, individual metal nanostructures need to be designed and fabricated for each independent chemical species. One possible solution to this …

Validation Of Quickscat Radiometer (Qrad) Microwave Brightness Temperture Measurments, Rafik Hanna

Electronic Theses and Dissertations

After the launch of NASA's SeaWinds scatterometer in 1999, a radiometer function was implemented in the Science Ground Data Processing Systems to allow the measurement of the earth's microwave brightness temperature. This dissertation presents results of a comprehensive validation to assess the quality of QRad brightness temperature measurements using near-simultaneous ocean Tb comparisons between the SeaWinds on QuikSCAT (QRad) and WindSat polarimetric radiometer on Coriolis. WindSat was selected because it is a well calibrated radiometer that has many suitable collocations with QuikSCAT; and it has a 10.7 GHz channel, which is close to QRad frequency of 13.4 GHz. Brightness temperature …

Embedded Magnetics For Power System On Chip (Psoc), Jian Lu

Electronic Theses and Dissertations

A novel concept of on-chip bondwire inductors and transformers with ferrite epoxy glob coating is proposed, offering a cost effective approach to realize power systems on chip (PSoC) or System-in-Package (PSiP). The concept has been investigated both experimentally and with finite element modeling. Improvement in total inductance is demonstrated for multi-turn bondwire inductors over single bondwire inductors. The inductance and Q factor can be further boosted with coupled multi-turn inductor concept. Transformer parameters including self- and mutual inductance, and coupling factors are extracted from both modeled and measured S-parameters. More importantly, the bondwire magnetic components can be easily integrated into …

Study Of Gate Oxide Breakdown And Hot Electron Effect On Cmos Circuit Performances, Jun Ma

Electronic Theses and Dissertations

In the modern semiconductor world, there is a significant scaling of the transistor dimensions--The transistor gate length and the gate oxide thickness drop down to only several nanometers. Today the semiconductor industry is already dominated by submicron devices and other material devices for the high transistor density and performance enhancement. In this case, the semiconductor reliability issues are the most important thing for commercialization. The major reliability issues caused by voltage are hot carrier effects (HCs) and gate oxide breakdown (BD) effects. These issues are recently more important to industry, due to the small size and high lateral field in …

Phase Shaping In The Infrared By Planar Quasi-Periodic Surfaces Comprised Of Sub-Wavelength Elements, James Ginn

Electronic Theses and Dissertations

Reflectarrays are passive quasi-periodic sub-wavelength antenna arrays designed for discrete reflected phase manipulation at each individual antenna element making up the array. By spatially varying the phase response of the antenna array, reflectarrays allow a planar surface to impress a non-planar phasefront upon re-radiation. Such devices have become commonplace at radio frequencies. In this dissertation, they are demonstrated in the infrared for the first time--at frequencies as high as 194 THz. Relevant aspects of computational electromagnetic modeling are explored, to yield design procedures optimized for these high frequencies. Modeling is also utilized to demonstrate the phase response of a generalized …

Unsupervised Building Detection From Irregularly Spaced Lidar And Aerial Imagery, Nicholas Shorter

Electronic Theses and Dissertations

As more data sources containing 3-D information are becoming available, an increased interest in 3-D imaging has emerged. Among these is the 3-D reconstruction of buildings and other man-made structures. A necessary preprocessing step is the detection and isolation of individual buildings that subsequently can be reconstructed in 3-D using various methodologies. Applications for both building detection and reconstruction have commercial use for urban planning, network planning for mobile communication (cell phone tower placement), spatial analysis of air pollution and noise nuisances, microclimate investigations, geographical information systems, security services and change detection from areas affected by natural disasters. Building detection …

Unified Large And Small Signal State-Space Based Modeling And Symbolic Simulation For Pwm Converters, Ehab Shoubaki

Electronic Theses and Dissertations

In this Dissertation, which concentrates on discrete modeling for control purposes of DC/DC converters and simulation through symbolic techniques. A Unified Discrete State-Space Model for power converters in CCM is presented. Two main approaches to arriving at the discrete model are used. The first approach involves an impulse function approximation of the duty cycle modulation of the converter switches, and this approach results in a small signal discrete model. The Second approach is direct and does not involve any approximation of the modulation, this approach yields both a large signal nonlinear discrete model and a linear small signal model. Harmonic …

Physical Properties Of Wave Scattering By Chiral Periodic Structure, Xiaomin Yang

Electronic Theses and Dissertations

Attention has been focused on electromagnetic chirality and its potential applications to microwave, millimeter wave and optical wave devices. In this work, wave propagation through a chiral periodic structure with arbitrary shape is investigated. Although perturbation theory and coupled-mode theory have been used to analyze chiral periodic structure, those are approximate methods and can only be used for low frequency applications. In this work, the rigorous mode-matching method is used to solve the problem. Staircase approximation is introduced to change the curved structure to a multilayer structure. The field solutions in the uniform air regions and unbounded air-chiral periodic array …

Control Of Nonh=Holonomic Systems, Hongliang Yuan

Electronic Theses and Dissertations

Many real-world electrical and mechanical systems have velocity-dependent constraints in their dynamic models. For example, car-like robots, unmanned aerial vehicles, autonomous underwater vehicles and hopping robots, etc. Most of these systems can be transformed into a chained form, which is considered as a canonical form of these nonholonomic systems. Hence, study of chained systems ensure their wide applicability. This thesis studied the problem of continuous feed-back control of the chained systems while pursuing inverse optimality and exponential convergence rates, as well as the feed-back stabilization problem under input saturation constraints. These studies are based on global singularity-free state transformations and …

Delay Modeling And Long-Range Predictive Control Of Czochralski Growth Process, Dhaval Shah

Electronic Theses and Dissertations

This work presents the Czochralski growth dynamics as time-varying delay based model, applied to the growth of La3Ga5.5Ta0.5O14 (LGT) piezoelectric crystals. The growth of high-quality large-diameter oxides by Czochralski technique requires the theoretical understanding and optimization of all relevant process parameters, growth conditions, and melts chemistry. Presently, proportional-integral- derivative (PID) type controllers are widely accepted for constant-diameter crystal growth by Czochralski. Such control systems, however, do not account for aspects such as the transportation delay of the heat from crucible wall to the crystal solidification front, heat radiated from the crucible wall above the melt surface, and varying melt level. …