Engineering Commons^™

Pipelining Of Double Precision Floating Point Division And Square Root Operations On Field-Programmable Gate Arrays, Anuja Thakkar

Electronic Theses and Dissertations

Many space applications, such as vision-based systems, synthetic aperture radar, and radar altimetry rely increasingly on high data rate DSP algorithms. These algorithms use double precision floating point arithmetic operations. While most DSP applications can be executed on DSP processors, the DSP numerical requirements of these new space applications surpass by far the numerical capabilities of many current DSP processors. Since the tradition in DSP processing has been to use fixed point number representation, only recently have DSP processors begun to incorporate floating point arithmetic units, even though most of these units handle only single precision floating point addition/subtraction, multiplication, …

Linux Based Pda Gateway For Wireless Sensor Networks, Áine Mccarthy

Theses

Recent years have seen a dramatic increase in the development and deployment of intelligent sensors and their use with a plethora of networking protocol technologies. Wireless Sensor Networks (WSN) can be used to monitor the environment, objects in the environment and the interaction of these objects with each other. Examples include environment and habitat monitoring, structural monitoring, disaster management and emergency response. The deployment of such large-scale WSN possess many challenges, the most important being scalability, portability, fault tolerance, adaptability and ubiquitous connectivity. There also exist many challenges when trying to establish communication with WSN. WSN can function as a …

Disappearing User Interface In Ubiquitous Computing: A Pointing And Gesture Sensing System Using An Ultrasonic And Radio Frequency Location Technology, Stephania Yimana Kigadye

Theses

Weiser’s [1] vision of ubiquitous computing presents a different paradigm of computing which attempts to push computers into the background towards invisibility. Therefore “new concepts for human-computer interaction have to be developed when envisioning ubiquitous computing scenarios [1]. Instead of a single screen-based user interface (UI), humans will interact with a number of devices that are distributed and interconnected. These eomputers range from highly personal and mobile applianees to systems that are integrated in everyday environments and are more or less invisible.”[7] As this project suggests, a disappearing user interface in ubiquitous computing can be designed as a gesture recognition …

Pocket Deformable Mirror For Adaptive Optics Applications, Leonid A. Beresnev, Mikhail Vorontsov, Peter Wangsness

Electrical and Computer Engineering Faculty Publications

Adaptive/active optical elements are designed to improve optical system performance in the presence of phase aberrations. For atmospheric optics and astronomical applications, an ideal deformable mirror should have sufficient frequency bandwidth for compensation of fast changing wave front aberrations induced by either atmospheric turbulences or by turbulent air flows surrounding a flying object (air optical effects). In many applications, such as atmospheric target tracking, remote sensing from flying aircraft, boundary layer imaging, laser communication and laser beam projection over near horizontal propagation paths the phase aberration frequency bandwidth can exceed several kHz. These fast-changing aberrations are currently compensated using relatively …

Adaptive Beam Director For A Tiled Fiber Array, Mikhail Vorontsov, Jim F. Riker, Ernst Polnau, Svetlana Lachinova, Venkata S. Rao Gudimetla

Electrical and Computer Engineering Faculty Publications

We present the concept development of a novel atmospheric compensation system based on adaptive tiled fiber array architecture operating with target-in-the-loop scenarios for directed beam applications. The adaptive tiled fiber array system is integrated with adaptive beam director (ABD). Wavefront control and sensing functions are performed directly on the beam director telescope primary mirror. The beam control of the adaptive tiled fiber array aims to compensate atmospheric turbulence-induced dynamic phase aberrations and results in a corresponding brightness increase on the illuminated extended object. The system is specifically designed for tiled fiber system architectures operating in strong intensity scintillation and speckle-modulation …

Experimental Comparison Of Wired Versus Wireless Video Streaming Over Ieee 802.11b Wlans, Tanmoy Debnath, Nicola Cranley, Mark Davis

Conference papers

In this paper the performance of streaming MPEG-4 video with a video server located on the wired network streaming to wireless clients is compared with the performance of a video server located in the wireless network streaming to wireless video clients. We experimentally investigate the performance for a number of concurrent video streams with varying video frame sizes, frame rates and packetisation schemes. The performance is measured in terms of the key parameters of bit rate, loss rate and mean delay. We show how that there is a trade-off for these parameters for a wired and wireless located server. We …

Analysis Of Strain And Intermixing In Single-Layer Ge/Si Quantum Dots Using Polarized Raman Spectroscopy, Anna Baranov, A. V. Federov, Tatiana Perova, R. A. Moore, V. Yam, D. Bouchier, V. Le Thanh, Kevin Berwick

Articles

The built-in strain and composition of as-grown and Si-capped single layers of Ge∕Si dots grown at various temperatures (460–800 °C) are studied by a comparative analysis of the Ge-Ge and Si-Ge modes in the polarized Raman spectra of the dots. A pronounced reduction of the strain and Ge content in the dots after deposition of the cap layer at low temperatures is observed, indicating that strain-induced Si diffusion from the cap layer is occurring. For large dots grown at 700–800 °C the observations are in agreement with a model of the Ge∕Si dot consisting of a Si-rich boundary region and …

Design Of One-Dimensional Composite Photonic Crystals With An Extended Photonic Band Gap, Vladimir Tolmachev, Kevin Berwick

Articles

A technique for photonic band gap (PBG) extension based on mixing photonic crystals with different lattice constants or filling factors is suggested. For the design of photonic crystals with maximal PBG extension the gap map imposition method is utilized. Gap maps for composite photonic crystals based on Si-air structures are calculated and used to predict optimal structures for fabrication.

Dsp Implementation Of Dc Voltage Regulation Using Adaptive Control For 200 Kw 62000 Rpm Induction Generator, Othman Elkhomri

Electronic Theses and Dissertations

The thesis discusses the development of closed loop system to control the DC voltage for 200 kW induction generator rated at a speed of 62000 RPM under different load conditions. The voltage regulation has been implemented using PI controller. A gain scheduling control algorithm has been developed to select the appropriate controller gains with respect to the generator load. Further, a relationship between the generator loads and the controller gains has been established. This relationship has been modeled using adaptive control technique to vary the gains automatically at any load condition. The adaptive control technique has been successfully generalized for …

The Effect Of Hot Carrier Stress On Low Noise Amplifier Radio Frequency Performance Under Weak And Strong Inversion, Lin Shen

Electronic Theses and Dissertations

This thesis work is mainly focused on studying RF performance degradation of a low noise amplifier (LNA) circuit due to hot carrier effect (HCE) in both the weak and strong inversion regions. Since the figures of merit for the RF circuit characterization are gain, noise figure, input, and output matching, the LNA RF performance drift is evaluated in a Cadence SpectreRF simulator subject to these features. This thesis presents hot carrier induced degradation results of an LNA to show that the HCE phenomenon is one of the serious reliability issues in the aggressively scaled RF CMOS design, especially for long-term …

Modeling And Optimization Of Body Diode Reverse Recovery Characteristics Of Ldmos Transistors, Wesley Deschaine

Electronic Theses and Dissertations

As switching speeds for DC-DC converter applications keep becoming faster and faster and voltage requirements become smaller and smaller, the need for new device structures becomes more prevalent. Designers of these new structures will need to make sure they take into consideration the different power losses associated with the different structures and make modifications to reduce or if possible eliminate them. A new 30V LDMOS device has been created and is being implemented into a synchronous buck converter for future DC-DC conversions. This new lateral device has a Figure of Merit of 80mÙ*nC, representing a 50% reduction from the conventional …

The Effectiveness Of Data Codes And Hardware Selection To Mitigate Scintillation Effects On Free Space Optical Data Transmission, Keith Stein

Electronic Theses and Dissertations

The design of an optical communication link must plan for the random effects of atmospheric turbulence. This study analyses data from an experiment which transmitted from a laser located 8 meters above ground over a 13 Km range to coherent detection devices approximately 162 meters above ground. The effects of a fading and surging beam wave were considered in regards to code techniques for error correction, amplitude modulation and hardware architecture schemes. This study simulated the use of arrays and large apertures for the receiving devices, and compared the resultant scintillation index with the theoretical calculations.

Text-Image Restoration And Text Alignment For Multi-Engine Optical Character Recognition Systems, Nikolai Kozlovski

Electronic Theses and Dissertations

Previous research showed that combining three different optical character recognition (OCR) engines (ExperVision® OCR, Scansoft OCR, and Abbyy® OCR) results using voting algorithms will get higher accuracy rate than each of the engines individually. While a voting algorithm has been realized, several aspects to automate and improve the accuracy rate needed further research. This thesis will focus on morphological image preprocessing and morphological text restoration that goes to OCR engines. This method is similar to the one used in restoration partial finger prints. Series of morphological dilating and eroding filters of various mask shapes and sizes were applied to text …

Design And Characterization Of Noveldevices For New Generation Of Electrostaticdischarge (Esd) Protection Structures, Javier Salcedo

Electronic Theses and Dissertations

The technology evolution and complexity of new circuit applications involve emerging reliability problems and even more sensitivity of integrated circuits (ICs) to electrostatic discharge (ESD)-induced damage. Regardless of the aggressive evolution in downscaling and subsequent improvement in applications' performance, ICs still should comply with minimum standards of ESD robustness in order to be commercially viable. Although the topic of ESD has received attention industry-wide, the design of robust protection structures and circuits remains challenging because ESD failure mechanisms continue to become more acute and design windows less flexible. The sensitivity of smaller devices, along with a limited understanding of the …

An Ocean Surface Wind Vector Model Function For A Spaceborne Microwave Radiometer And Its Application, Seubson Soisuvarn

Electronic Theses and Dissertations

Ocean surface wind vectors over the ocean present vital information for scientists and forecasters in their attempt to understand the Earth's global weather and climate. As the demand for global wind velocity information has increased, the number of satellite missions that carry wind-measuring sensors has also increased; however, there are still not sufficient numbers of instruments in orbit today to fulfill the need for operational meteorological and scientific wind vector data. Over the last three decades operational measurements of global ocean wind speeds have been obtained from passive microwave radiometers. Also, vector ocean surface wind data were primarily obtained from …

Study Of Nanoscale Cmos Device And Circuit Reliability, Chuanzhao Yu

Electronic Theses and Dissertations

The development of semiconductor technology has led to the significant scaling of the transistor dimensions -The transistor gate length drops down to tens of nanometers and the gate oxide thickness to 1 nm. In the future several years, the deep submicron devices will dominate the semiconductor industry for the high transistor density and the corresponding performance enhancement. For these devices, the reliability issues are the first concern for the commercialization. The major reliability issues caused by voltage and/or temperature stress are gate oxide breakdown (BD), hot carrier effects (HCs), and negative bias temperature instability (NBTI). They become even more important …

Debris Characterization And Mitigation Of Droplet Laser Plasma Sources For Euv Lithography, Kazutoshi Takenoshita

Electronic Theses and Dissertations

Extreme ultraviolet lithography (EUVL) is a next generation lithographic techniques under development for fabricating semiconductor devices with feature sizes smaller than 32 nm. The optics to be used in the EUVL steppers is reflective optics with multilayer mirror coatings on each surface. The wavelength of choice is 13.5 nm determined by the optimum reflectivity of the mirror coatings. The light source required for this wavelength is derived from a hot-dense plasma produced by either a gas discharge or a laser. This study concentrate only on the laser produced plasma source because of its advantages of scalability to higher repetition rates. …

An Improved Microwave Radiative Transfer Model For Ocean Emissivity At Hurricane Force Surface Wind Speed, Salem El-Nimri

Electronic Theses and Dissertations

An electromagnetic model for predicting the microwave blackbody emission from the ocean surface under the forcing of strong surface winds in hurricanes is being developed. This ocean emissivity model will be incorporated into a larger radiative transfer model used to infer ocean surface wind speed and rain rate in hurricanes from remotely sensed radiometric brightness temperature. The model development is based on measurements obtained with the Stepped Frequency Microwave Radiometer (SFMR), which routinely flys on the National Oceanic and Atmospheric Administration's hurricane hunter aircraft. This thesis presents the methods used in the wind speed model development and validation results for …

Wide Viewing Angle Liquid Crystal Displays, Qi Hong

Electronic Theses and Dissertations

In this dissertation, novel phase compensation technologies are applied to the designs of wide viewing angle and high transmittance liquid crystal displays. First, a design of wide viewing angle liquid crystal displays utilizing crossed linear polarizers is proposed. The designed multi-domain vertical-alignment liquid crystal display predicts superb contrast ratio over wide viewing angles. Next, to increase the bright state transmittance while maintain the high contrast. Finally, to reduce the cost and improve the applicability of the broadband and wide-view circular polarizer, the device configuration of the broadband and wide-view circular polarizer is significantly simplified by the application of biaxial compensation …

On-Chip Spiral Inductor/Transformer Design And Modeling For Rf Applications, Ji Chen

Electronic Theses and Dissertations

Passive components are indispensable in the design and development of microchips for high-frequency applications. Inductors in particular are used frequently in radio frequency (RF) IC's such as low-noise amplifiers and oscillators. High performance inductor has become one of the critical components for voltage controlled oscillator (VCO) design, for its quality factor (Q) value directly affects the VCO phase noise. The optimization of inductor layout can improve its performance, but the improvement is limited by selected technology. Inductor performance is bounded by the thin routing metal and small distance from lossy substrate. On the other hand, the in-accurate inductor modeling further …

Design, Analysis And Implementation Of Orthogonal Frequency Coding In Saw Devices Used For Spread Spectrum Tags And Sensors, Derek Puccio

Electronic Theses and Dissertations

SAW based sensors can offer wireless, passive operation in numerous environments and various device embodiments are employed for retrieval of the sensed data information. Single sensor systems can typically use a single carrier frequency and a simple device embodiment, since tagging is not required. In a multi-sensor environment, it is necessary to both identify the sensor and retrieve the sensed information. This dissertation presents the concept of orthogonal frequency coding (OFC) for applications to SAW sensor technology. OFC offers all advantages inherent to spread spectrum communications including enhanced processing gain and lower interrogation power spectral density (PSD). It is shown …

Transmission Lines For Ir Signal Routing, Tasneem Mandviwala

Electronic Theses and Dissertations

In this dissertation, the design, fabrication, and characterization of coplanar striplines, vias, and microstrip lines is investigated, from the point of view of developing interconnections for antenna-coupled infrared detectors operating in the 8- to 12-micron wavelength range. To our knowledge, no previous efforts have been made to study the performance of metallic-wire transmission lines at infrared frequencies. Both the design and fabrication of these structures present unique challenges. Because of attenuation and dispersion issues, the analytical formulas for transmission-line parameters that are valid below a few hundred GHz are not applicable in the infrared. Therefore, numerical modeling was performed to …

Heuristic 3d Reconstruction Of Irregular Spaced Lidar, Nicholas Shorter

Electronic Theses and Dissertations

As more data sources have become abundantly available, an increased interest in 3D reconstruction has emerged in the image processing academic community. Applications for 3D reconstruction of urban and residential buildings consist of urban planning, network planning for mobile communication, tourism information systems, spatial analysis of air pollution and noise nuisance, microclimate investigations, and Geographical Information Systems (GISs). Previous, classical, 3D reconstruction algorithms solely utilized aerial photography. With the advent of LIDAR systems, current algorithms explore using captured LIDAR data as an additional feasible source of information for 3D reconstruction. Preprocessing techniques are proposed for the development of an autonomous …

Wideband Dual Polarized Directional Base Station Antenna, Francisco L. Lerma

Masters

The thesis presents a study of different microwave radiators for wireless applications in the frequency range of 2.2 – 2.5GHz. The performance of microstrip patch antennas and dual polarized dipole antennas were evaluated numerically and experimentally verified. A single microstrip patch and a four- element microstrip array were simulated, fabricated and tested. Simulation was carried out by the finite integration time domain (FITD) method. Polarization diversity is realised using crossed dipoles printed elements. For the crossed dipole elements, two different feed arrangements were studied. Parameters such as return loss, isolation, radiation pattern, gain and bandwidth were measured and found to …

System Identification Of A Pasteurisation Process: A Comparison Of Direct And Indirect Methods, Niel Canty

Theses

The primary focus of this research is to identify a linear model for a direct steam injection (DSI) pasteurisation process which is a component of a large-scale pilot evaporation process widely used in the dairy industry. The pasteurisation process has been identified as a key component of the evaporation process. The author believes that no previously published work has focused on identifying models for a DSI pasteurisation process which makes this work an original contribution to the area. The pasteurisation process can be modelled as a single-input, single-output (SISO) process with a measurable disturbance. Thus two transfer functions were required …

Next Generation Heterogenous Telemetry Modules, Pierce Brady

Theses

Remote monitoring is used in many applications within the scientific, industrial and commercial communities. These applications can range from the simple monitoring of wind farm generators to the complex behavioural monitoring of a local fox habitat to the simple but extremely urgent monitoring of water depth for a flood prone river. Each application of remote monitoring requires different aspects of the remote monitoring device, but typically, not all these applications can be implemented, as the technologies required for their construction are extremely large, expensive, energy inefficient, slow and do not meet the constraints for the given application.

However with the …

Efficient Strategies For Robust Constrained Model Predictive Control, Marcin Tomasz Cychowski

Theses

Practical difficulties associated with the implementation of stabilizing robust model predictive control (MPC) laws are well known. The algorithms typically rely on the solution of the so-called min-max optimization problem. All such algorithms display a large online computational burden and often suffer excessive conservativeness. In this thesis, two original algorithms will be developed that address the conservativeness and complexity issues in min-max MPC.

The first algorithm is a min-max MPC based on the concept of closed-loop prediction. The synthesis procedure is realized using linear matrix inequalities and thus the implementation of the closed-loop min-max MPC control law can be performed …

Hurricane Wind Speed And Rain Rate Retrieval Algorithm For The Stepped Frequency Microwave Radiometer, Ruba Amarin

Electronic Theses and Dissertations

This thesis presents the development and validation of the Hurricane Imaging Retrieval Algorithm (HIRA) for the measurement of oceanic surface wind speed and rain rate in hurricanes. The HIRA is designed to process airborne microwave brightness temperatures from the NOAA, Stepped Frequency Microwave Radiometer (SFMR), which routinely collects data during NOAA hurricane hunter aircraft flights. SFMR measures wind speeds and rain rates at nadir only, but HIRA will soon be integrated with an improved surface wind speed model for expanded utilization with next generation microwave hurricane imagers, such as the Hurricane Imaging Radiometer (HIRad). HIRad will expand the nadir only …

Chirp Signaling Offers Modulation Scheme For Underwater Communications, Edit J. Kaminsky

Electrical Engineering Faculty Publications

Information contained in the slope of chirp signals can be employed for digital underwater acoustic communications across a broad range of applications.

Fuzzy-Neural Cost Estimation For Engine Tests, Edit J. Kaminsky, Holly Danker-Mcdermott, Freddie Douglas

Electrical Engineering Faculty Publications

This chapter discusses artificial computational intelligence methods as applied to cost prediction. We present the development of a suite of hybrid fuzzy-neural systems for predicting the cost of performing engine tests at NASA’s Stennis Space Center testing facilities. The system is composed of several adaptive network-based fuzzy inference systems (ANFIS), with or without neural subsystems. The output produced by each system in the suite is a rough order of magnitude (ROM) cost estimate for performing the engine test. Basic systems predict cost based solely on raw test data, whereas others use preprocessing of these data, such as principal components and …