Engineering Commons^™

Cyclic Prefix Assisted Block Transmission For Low Complexity Communication System Design, Haibin Huang

Theses

This thesis presents new results on cyclic prefix (CP) assisted block transmission for low complexity communication system design. Two important aspects are studied: the CP based low-complexity schemes for channel equalization and channel estimation.

Specifically, based on the simple frequency domain equalization, a low complexity joint receiver is proposed for CP-CDMA system, which is a special application of block transmission.

And in this work the finite impulse response (FIR) model is used for the unknown communication channels. To identify an unknown FIR channel, a novel channel estimation method is proposed by exploiting the cyclic prefix technique. Compared to a conventional …

A Digital Signature And Watermarking Based Authentication System For Jpeg2000 Images, Rui Jing

Theses

In this thesis, digital signature based authentication system was introduced, which is able to protect JPEG2000 images in different flavors, including fragile authentication and semi-fragile authentication. The fragile authentication is to protect the image at code-stream level, and the semi-fragile is to protect the image at the content level.

The semi-fragile can be further classified into lossy and lossless authentication. With lossless authentication, the original image can be recovered after verification. The lossless authentication and the new image compression standard, JPEG2000 is mainly discussed in this thesis.

Study Of Joint Embedding And Compression On Jpeg Compression Scheme Using Multiple Codebook Data Hiding, Amol Nishikant Sukerkar

Theses

This thesis studies a direct application of multiple codebook data hiding technique in the multimedia applications. It studies the practical implementation of a joint embedding and compression scheme. It presents a study of Type III data embedding technique using multiple codebook design on JPEG-85 compression scheme. The application of the above technique is compared with the Type III data embedding techniques using single codebook design. The comparison is carried out in tenns of the parameters such as mean square error and normalized correlation between the embedded and extracted watermark.

The performance of data hiding rate against the embedding distortion is …

Optical Properties Of Sige Nanostructures, Varun Sharma

Theses

In this thesis, Raman Scattering (RS) and photoluminescence (PL) measurements of Ge nanowires (NWs) grown via vapor-liquid-solid (VLS) using chemical vapor deposition silicon substrates consisting of (100) and (111) crystallographic orientations are reported. Ge NWs grown are ~40 nm in diameter, approximately a micrometer in length, and a sharp narrow Raman peak at ~300cm^-1 indicates single crystal quality. An absence of SiGe peak in the Raman spectra indicates that SiGe interdiffusion is insignificant for the NW volume. Low temperature PL-intensity-dependence spectra indicate that the observed emission originates at the Ge NW - Si substrate interface, where SiGe intermixing has …

Single-Layer-Coated Beam Splitters For The Division-Of-Amplitude Photopolarimeter, Rasheed M.A. Azzam, Faisal F. Sudradjat

Electrical Engineering Faculty Publications

A design procedure is presented for a near-optimal, single-layer-coated prism beam splitter that serves as the key optical element of the division-of-amplitude photopolarimeter (DOAP). For given film and substrate refractive indices, the angle of incidence and film thickness are selected such that the ellipsometric differential phase shifts in reflection and transmission Delta_r and Delta_t differ by ±pi/2, and the normalized determinant of the instrument matrix is maximized. The best results are obtained by using high-index films on low-index substrates. This is illustrated by examples of ZnS and GaP films on silica prisms in the visible and Si, Ge, and PbTe …

Performance Analysis Of Network-Level Qos With Encoding Configuration For Unicast Video Streaming Over Ieee 802.11 Wlan Networks, Nicola Cranley, Mark Davis

Conference papers

Video streaming has a large impact on the resource requirements of the WLAN. However, there are many variables involved in video streaming, such as the video content being streamed, how the video is encoded and how it is sent. This makes the role of radio resource management extremely difficult. In this paper we investigate the effect that video encoding configurations has on the network resource requirements for unicast video streaming in a WLAN environment. We compare the network resource requirements of several content types encoded at various encoding configurations with varying I-frame frequencies, target encoding bit rates and hint track …

Seawinds Radiometer Brightness Temperature Calibration And Validation, Mayank Rastogi

Electronic Theses and Dissertations

The NASA SeaWinds scatterometer is a radar remote sensor which operates on two satellites; NASA's QuikSCAT launched in June 1999 and on Japan's ADEOS-II satellite launched in December 2002. The purpose of SeaWinds is to provide global measurements of the ocean surface wind vector. On QuikSCAT, a ground data processing algorithm was developed, which allowed the instrument to function as a QuikSCAT Radiometer (QRad) and measure the ocean microwave emissions (brightness temperature, Tb) simultaneously with the backscattered power. When SeaWinds on ADEOS was launched, this same algorithm was applied, but the results were anomalous. The initial SRad brightness temperatures exhibited …

Unified Large And Small Signal Discrete-Space Modeling For Pwm Converters In Ccm, Ehab Hamed Shoubaki

Electronic Theses and Dissertations

In this Thesis 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 modulations 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 modulations , this approach yields both a large signal nonlinear discrete model and a linear small signal model. Harmonic analysis of the converter states at steady-state is done for steady-state waveform acquisition , …

Background Stabilization And Motion Detection In Launch Pad Video Monitoring, Kaushik Gopalan

Electronic Theses and Dissertations

Automatic detection of moving objects in video sequences is a widely researched topic with application in surveillance operations. Methods based on background cancellation by frame differencing are extremely common. However this process becomes much more complicated when the background is not completely stable due to camera motion. This thesis considers a space application where surveillance cameras around a shuttle launch site are used to detect any debris from the shuttle. The ground shake due to the impact of the launch causes the background to be shaky. We stabilize the background by translation of each frame, the optimum translation being determined …

Use Of Advanced Synthesis Tools In Teaching Vlsi Design, Kevin Berwick, Dominic Nardone

Articles

No abstract provided.

Predictive Control For Dynamic Systems To Track Unknown Input In The Presence Of Time Delay, Yulan Li

Electronic Theses and Dissertations

This study investigated a tracking system to trace unknown signal in the presence oftime delay. A predictive control method is proposed in order to compensate the time delay. Root locus method is applied when designing the controller, parameter setting is carried out through error and trail technique in w-plane. State space equation is derived for the system, with special state chose of tracking error. To analyze the asymptotic stability of the proposed predictive control system, the Lyapunov function is constructed. It is shown that the designed system is asymptotically stable when input signal is rather low frequency signal. In order …

Analysis And Simulation Tools For Solar Array Power Systems, Nattorn Pongratananukul

Electronic Theses and Dissertations

This dissertation presents simulation tools developed specifically for the design of solar array power systems. Contributions are made in several aspects of the system design phases, including solar source modeling, system simulation, and controller verification. A tool to automate the study of solar array configurations using general purpose circuit simulators has been developed based on the modeling of individual solar cells. Hierarchical structure of solar cell elements, including semiconductor properties, allows simulation of electrical properties as well as the evaluation of the impact of environmental conditions. A second developed tool provides a co-simulation platform with the capability to verify the …

Optimization Of Network Parameters And Semi-Supervision In Gaussian Art Architectures, Roopa Chalasani

Electronic Theses and Dissertations

In this thesis we extensively experiment with two ART (adaptive resonance theory) architectures called Gaussian ARTMAP (GAM) and Distributed Gaussian ARTMAP (dGAM). Both of these classifiers have been successfully used in the past on a variety of applications. One of our contributions in this thesis is extensively experiments with the GAM and dGAM network parameters and appropriately identifying ranges for these parameters for which these architectures attain good performance (good classification performance and small network size). Furthermore, we have implemented novel modifications of these architectures, called semi-supervised GAM and dGAM architectures. Semi-supervision is a concept that has been used effectively …

Analysis And Design Of A Modular Solar-Fed Fault-Tolerant Power System With Maximum Power Point Tracking, Hussam Al-Atrash

Electronic Theses and Dissertations

Solar power is becoming ever more popular in a variety of applications. It is particularly attractive because of its abundance, renewability, and environment friendliness. Solar powered spacecraft systems have ever-expanding loads with stringent power regulation specifications. Moreover, they require a light and compact design of their power system. These constraints make the optimization of power harvest from solar arrays a critical task. Florida Power Electronics Center (FPEC) at UCF set to develop a modular fault-tolerant power system architecture for space applications. This architecture provides a number of very attractive features including Maximum Power Point Tracking (MPPT) and uniform power stress …

Detection Of The R-Wave In Ecg Signals, Sasanka Valluri

Electronic Theses and Dissertations

This thesis aims at providing a new approach for detecting R-waves in the ECG signal and generating the corresponding R-wave impulses with the delay between the original R-waves and the R-wave impulses being lesser than 100 ms. The algorithm was implemented in Matlab and tested with good results against 90 different ECG recordings from the MIT-BIH database. The Discrete Wavelet Transform (DWT) forms the heart of the algorithm providing a multi-resolution analysis of the ECG signal. The wavelet transform decomposes the ECG signal into frequency scales where the ECG characteristic waveforms are indicated by zero crossings. The adaptive threshold algorithms …

Design And Implementation Of Wireles Sensor Networks For Parking Management System, Sudhir Chandrasekar Kora

Electronic Theses and Dissertations

The technology of wirelessly networked micro sensors promises to revolutionize the way we interact with the physical environment. A new approach to solve parking-related issues of vehicles in parking lots using wireless sensor networks is presented. This approach enables the implementation of the Parking Management System (PMS®) in public parking lots found in Airports, Commercial Buildings, Universities, etc. The design architecture of the sensor nodes is discussed here. An overall view of the sensor network, which covers the whole of the parking lot, is also summarized. Detailed description of the software architecture that supports the hardware is provided. A sample …

Frequency Domain Independent Component Analysis Applied To Wireless Communications Over Frequency-Selective Channels, Yuan Liu

Electronic Theses and Dissertations

In wireless communications, frequency-selective fading is a major source of impairment for wireless communications. In this research, a novel Frequency-Domain Independent Component Analysis (ICA-F) approach is proposed to blindly separate and deconvolve signals traveling through frequency-selective, slow fading channels. Compared with existing time-domain approaches, the ICA-F is computationally efficient and possesses fast convergence properties. Simulation results confirm the effectiveness of the proposed ICA-F. Orthogonal Frequency Division Multiplexing (OFDM) systems are widely used in wireless communications nowadays. However, OFDM systems are very sensitive to Carrier Frequency Offset (CFO). Thus, an accurate CFO compensation technique is required in order to achieve acceptable …

Control And Topology Improvements In Half-Bridge Dc-Dc Converters, Songquan Deng

Electronic Theses and Dissertations

Efficiency and transient response are two key requirements for DC-DC converters. Topology and control are two key topics in this dissertation. A variety of techniques for DC-DC converter performance improvement are presented in this work. Focusing on the efficiency issue, a variety of clamping techniques including both active and passive methods are presented after the ringing issues in DC-DC converters are investigated. By presenting the clamping techniques, a big variety of energy management concepts are introduced. The active bridge-capacitor tank clamping and FET-diode-capacitor tank clamping are close ideas, which transfer the leakage inductor energy to clamping capacitor to prevent oscillation …

Debris Tracking In A Semistable Background, Karthikkalathi Vanumamalai

Electronic Theses and Dissertations

Object Tracking plays a very pivotal role in many computer vision applications such as video surveillance, human gesture recognition and object based video compressions such as MPEG-4. Automatic detection of any moving object and tracking its motion is always an important topic of computer vision and robotic fields. This thesis deals with the problem of detecting the presence of debris or any other unexpected objects in footage obtained during spacecraft launches, and this poses a challenge because of the non-stationary background. When the background is stationary, moving objects can be detected by frame differencing. Therefore there is a need for …

The Effect Of The Internal Field On The Ir Absorption Spectra Of Small Particles In Case Of 3d, 2d And 1d Size Confinement, Igor I. Shaganov, Tatiana S. Perova, R. Alan Moore, Kevin Berwick

Articles

The spectral properties of composite materials based on small particles under 1D, 2D, and 3D size confinement are described using a combination of dispersive internal field and effective media theory approaches. Calculations performed for a number of crystalline materials have shown that the peak position and intensity of the vibrational band of the material under conditions of 1D, 2D, and 3D size confinement are changed, whereas the bandwidth of the band remains the same. In the case of 3D confinement, the peak position of the spectrum of isolated “mesoparticles” ( ) appears to be very close to the intrinsic frequency …

Investigation Of High-K Gate Dielectrics And Metals For Mosfet Devices., Sriram Mannargudi Seshadri

Electronic Theses and Dissertations

Progress in advanced microlithography and deposition techniques have made feasible high- k dielectric materials for MOS transistors. The continued scaling of CMOS devices is pushing the Si-SiO2 to its limit to consider high-k gate dielectrics. The demand for faster, low power, smaller, less expensive devices with good functionality and higher performance increases the demand for high-k dielectric based MOS devices. This thesis gives an in-depth study of threshold voltages of PMOS and NMOS transistors using various high-k dielectric materials like Tantalum pent oxide (Ta2O5), Hafnium oxide (HfO2), Zirconium oxide (ZrO2) and Aluminum oxide (Al2O3) gate oxides. Higher dielectric constant may …

Real-Time Multi-Spectral Image Processing On The Adsp-Bf533 Dsp, Stephen Niall Coffey

Theses

As the need to process multi-spectral images in real-time is becoming more prevalent, the pressure on Integrated Circuit (IC) manufacturers to produce cheap and reliable devices capable of handling the demands of such operations is growing. This project investigates the ADSP-BF533 Blackfin® Digital Signal Processor (DSP) and its ability to support a real-time multi-spectral imaging system. The Blackfin® DSP, incorporating the Analog Devices/Intel Micro Signal Architecture (MSA), are a broad family of 16-bit fixed-point product with a dual Multiply Accumulate (MAC) core.

Using the MicroC/OS-II Real-time Operating System (RTOS), which is a completely portable and scaleable pre-emptive real-time kernel, the …

A 10-Bit 100msample/S Pipeline Analog- To-Digital Converter In Cmos, Pieter Berkelaar

Theses

High speed, medium resolution ADC’s, are required for many applications, including wireless receivers, ultrasound systems, wireline interfaces, cameras and camcorders. Low power dissipation is important, particularly for portable equipment where battery life must be maximised. The pipeline ADC architecture is particularly suited to such applications. Its strength comes from the manner in which it performs a conversion, distributing the work in time and amongst successive stages. These stages operate concurrently, maintaining high throughput. Each stage is made up of a fully differential switched capacitor sample-and- hold amplifier and some other circuitry. Designing these circuits to operate at l00MHz is extremely …

Robust Colour Segmentation Under Dynamic Lighting Conditions, Noreen Mary Looney

Theses

Traditionally, the issue of colour constancy has limited the success of colour image segmentation algorithms. Numerous methods exist to achieve colour constancy for different applications. The principal contribution of this thesis is the investigation of a suitable technique for the problem of robust colour based object detection.

Appropriate colour models are investigated and analysed in order to assess their ability to enhance the isolation process. Models that possess suitable colour constancy characteristics are chosen for use with image segmentation algorithms. Reviews of existing sur\'eys of image segmentation algorithms are appraised for the emergence of a suitable colour image segmentation technique. …

Signal Flow Analysis, Partha P. Banerjee

Electrical and Computer Engineering Faculty Publications

Signal flow graphs are a viable alternative to block diagrammatic representation of a system. What makes signal flow graphs attractive is that certain features from graph theory can be applied to the simplification and the synthesis of complex systems.

Functional Nanoparticles In Thin Films As Sensing Media, Elena A. Guliants, Ryan Schwarb, Hope Bearbower, James R. Gord, Christopher E. Bunker

Electrical and Computer Engineering Faculty Publications

The combination of unique properties offered by materials on the nanoscale with the increased role of surface chemistry in nanostructured solids makes core-shell nanoparticles extremely attractive for application to "smart" thin-film coatings. Sensing properties of nanoparticle-based thin films were studied in several systems containing organic-coated semiconductor and metallic particles. In semiconductors, the interaction of organic shell and/or thin-film "matrix" with the environment results in changes in the nanoparticle's surface states, altering the optical properties of the thin film. Measuring the electrical properties of thin films composed of metallic cores with hydrocarbon shells offers another mechanism to monitor the local environment …

Predicted Properties Of Microhollow Cathode Discharges In Xenon, J. P. Boeuf, L. C. Pitchford, K. H. Schoenbach

Bioelectrics Publications

A fluid model has been developed and used to help clarify the physical mechanisms occurring in microhollow cathode discharges (MHCD). Calculated current-voltage (I-V) characteristics and gas temperatures in xenon at 100 Torr are presented. Consistent with previous experimental results in similar conditions, we find a voltage maximum in the I-V characteristic. We show that this structure reflects a transition between a low-current, abnormal discharge localized inside the cylindrical hollow cathode to a higher-current, normal glow discharge sustained by electron emission from the outer surface of the cathode. This transition, due to the geometry of …

A Novel Framework For Radio Resource Management In Ieee 802.11 Wireless Lans, Mark Davis, Tristan Raimondi

Conference papers

In this paper we address the need to characterize and quantify resource usage in IEEE 802.11 WLANs in order to support radio resource management. We present a compact and intuitive framework for performance characterization and resource utilization that is based upon the concept of MAC bandwidth components. These MAC bandwidth components are directly related to the transmission rate and serve to quantify the resource requirements associated with accessing the wireless medium. We also introduce a graphical technique for presenting these MAC bandwidth components that illustrates how WLAN stations interact in contending for access to the wireless medium. We demonstrate the …

Study Of Oxide Breakdown, Hot Carrier And Nbti Effects On Mos Device And Circuit Reliability, Yi Liu

Electronic Theses and Dissertations

As CMOS device sizes shrink, the channel electric field becomes higher and the hot carrier (HC) effect becomes more significant. When the oxide is scaled down to less than 3 nm, gate oxide breakdown (BD) often takes place. As a result, oxide trapping and interface generation cause long term performance drift and related reliability problems in devices and circuits. The RF front-end circuits include low noise amplifier (LNA), local oscillator (LO) and mixer. It is desirable for a LNA to achieve high gain with low noise figure, a LO to generate low noise signal with sufficient output power, wide tuning …

Giant Magneto-Impedance Effect In Thin Film Layered Structures, Amruta Borge

Electronic Theses and Dissertations

Recently, the giant magneto impedance (GMI) effect has been studied extensively because of its potential applications in sensor elements. The focus of this thesis work is to explore different compositions and processing conditions for CoSiB and NiFe thin films to obtain the soft magnetic properties and to evaluate their potential use in GMI sensor applications. Prior to this study, an MH Looper was constructed, which was extremely important and provided the basic magnetic characterization of the many ferromagnetic thin films deposited during this work. The CoSiB films were co-sputter deposited in an ultra high vacuum chamber. Films with different relative …