Engineering Commons^™

Contrast Measure-Based Automated Regularization Parameter Selection For Radar Image Restoration, Cher Hau Seng, Abdesselam Bouzerdoum, Son Lam Phung

Cher Hau Seng

Images formed by acquisition devices are usually corrupted by noise and other interferences. Hence, regularization methods have been introduced to restore the degraded images and obtain solutions that are stable in the presence of perturbations. While the regularization parameter is crucial to the characteristics of the restoration, most existing selection methods either require memory-intensive computation or prior knowledge of the noise [1]. Moreover, the use of a small regularization parameter will produce a restoration that is dominated by large, high frequency noise components, whereas large regularization parameter imposes greater importance on the regularizer, causing important information to be lost. Therefore, …

Quality-Driven Cross Layer Design For Multimedia Security Over Resource Constrained Wireless Sensor Networks, Wei Wang

Computer and Electronics Engineering: Dissertations, Theses, and Student Research

The strong need for security guarantee, e.g., integrity and authenticity, as well as privacy and confidentiality in wireless multimedia services has driven the development of an emerging research area in low cost Wireless Multimedia Sensor Networks (WMSNs). Unfortunately, those conventional encryption and authentication techniques cannot be applied directly to WMSNs due to inborn challenges such as extremely limited energy, computing and bandwidth resources. This dissertation provides a quality-driven security design and resource allocation framework for WMSNs. The contribution of this dissertation bridges the inter-disciplinary research gap between high layer multimedia signal processing and low layer computer networking. It formulates the …

Detection And Tracking Of Stealthy Targets Using Particle Filters, Philip M. Losie

Master's Theses

In recent years, the particle filter has gained prominence in the area of target tracking because it is robust to non-linear target motion and non-Gaussian additive noise. Traditional track filters, such as the Kalman filter, have been well studied for linear tracking applications, but perform poorly for non-linear applications. The particle filter has been shown to perform well in non-linear applications. The particle filter method is computationally intensive and advances in processor speed and computational power have allowed this method to be implemented in real-time tracking applications. This thesis explores the use of particle filters to detect and track stealthy …

Psuedo-Randomly Controlled Analog Synthesizer, Jared Huntington

Electrical Engineering

The goal of this project was to design and build a portable box recreating classic sounds heard in science fiction films. These include sounds ranging from droning hums to bloops and bleeps. Currently no other device is made specifically for generating these sounds. The user controls and manipulates the sounds produced using a combination of switches and knobs to shape the sound generation. The sounds are generated using analog electronics. The project was successful in meeting the desired goal by designing and building a Randomizer, MIDI controller, VCO, LFO, VCA, Ring Modulator, and Fuzz Section. The resulting device is useful …

Violin Note Detector Using Digital Signal Processing, Nathaniel Kyle Mopas

Electrical Engineering

No abstract provided.

Rigid And Non-Rigid Point-Based Medical Image Registration, Nestor Andres Parra

FIU Electronic Theses and Dissertations

The primary goal of this dissertation is to develop point-based rigid and non-rigid image registration methods that have better accuracy than existing methods. We first present point-based PoIRe, which provides the framework for point-based global rigid registrations. It allows a choice of different search strategies including (a) branch-and-bound, (b) probabilistic hill-climbing, and (c) a novel hybrid method that takes advantage of the best characteristics of the other two methods. We use a robust similarity measure that is insensitive to noise, which is often introduced during feature extraction. We show the robustness of PoIRe using it to register images obtained with …

Sensor Integration For Low-Cost Crash Avoidance, Stephane M. Roussel

Master's Theses

This report is a summary of the development of sensor integration for low-cost crash avoidance for over-land commercial trucks. The goal of the project was to build and test a system composed of low-cost commercially available sensors arranged on a truck trailer to monitor the environment around the truck. The system combines the data from each sensor to increase the reliability of the sensor using a probabilistic data fusion approach. A combination of ultrasonic and magnetoresistive sensors was used in this study. In addition, Radar and digital imaging were investigated as reference signals and possible candidates for additional sensor integration. …

Anomaly Detection In Hyperspectral Imagery: Comparison Of Methods Using Diurnal And Seasonal Data, Patrick C. Hytla, Russell C. Hardie, Michael T. Eismann, Joseph Meola

Electrical and Computer Engineering Faculty Publications

The use of hyperspectral imaging is a fast growing field with many applications in the civilian, commercial and military sectors. Hyperspectral images are typically composed of many spectral bands in the visible and infrared regions of the electromagnetic spectrum and have the potential to deliver a great deal of information about a remotely sensed scene. One area of interest regarding hyperspectral images is anomaly detection, or the ability to find spectral outliers within a complex background in a scene with no a priori information about the scene or its specific contents. Anomaly detectors typically operate by creating a statistical background …

Simulation Of Mc-Ds-Cdma-System Based On: Multi-Wavelets Transform Over Wireless Channel, Amean Al_Safi

Amean S Al_Safi

In this paper a scheme was proposed to improve the performance form the Bit Error Rate (BER) view point for Multicarrier-Direct-Sequence-Code Division Multiple Access (MC-DS-CDMA) system in wireless channel. The conventional MC-DS-CDMA-system is based on Fast Fourier Transform (FFT). The proposed system was based on Multi-Wavelet transform (MWT). Simulation results are done in three different types of channels. Simulation shows that the proposed system outperforms the conventional system in addition to a coded version of the conventional system. Also the MC-DS-CDMA-system which is based on MWT achieves better performance with the same loss in bandwidth than the MC-DS-CDMA-system based on …

Networks - I: An Instantiation Of Way Point Routing For Mobile Ad Hoc Networks, Waseem M. Arain, Sayeed Ghani

International Conference on Information and Communication Technologies

Mobile ad hoc networks are increasingly finding their existence in the marketplace heading to a new paradigm of pervasive computing. However there are many areas open to research in the field. Due to node mobility resulting in an ever-changing network topology, conventional routing methods cannot be applied in MANETS. Therefore, this is one of the core areas of research. Researchers are challenged to design protocols that can potentially scale to anything from thousand to tens of thousands of nodes and to reduce the route discovery latency. In this paper a different instantiation of way point routing (WPR) model is proposed, …

A Trade-Off Analysis Of Energy Detectors And Partitioned Search For Primary Detection, Robert H. Morelos-Zaragoza, Birsen Sirkeci, Vishal Sawant

Robert Henry Morelos-Zaragoza

Cognitive radios aim to coexist in the unused spectrum bands which are licensed to primary users without harming the primary transmission/reception. For a cognitive radio, it is important to detect the band in which the primary is operating as fast as possible and with high reliability in order to adapt its transmission. In this work, we propose P-partitioning method in combination with energy detectors for the search of the band that the primary user is operating.

Scene-Based Nonuniformity Correction With Reduced Ghosting Using A Gated Lms Algorithm, Russell C. Hardie, Frank Orion Baxley, Brandon J. Brys, Patrick C. Hytla

Electrical and Computer Engineering Faculty Publications

In this paper, we present a scene-based nouniformity correction (NUC) method using a modified adaptive least mean square (LMS) algorithm with a novel gating operation on the updates. The gating is designed to significantly reduce ghosting artifacts produced by many scene-based NUC algorithms by halting updates when temporal variation is lacking. We define the algorithm and present a number of experimental results to demonstrate the efficacy of the proposed method in comparison to several previously published methods including other LMS and constant statistics based methods. The experimental results include simulated imagery and a real infrared image sequence. We show that …

Abstracting Gis Layers From Hyperspectral Imagery, Torsten E. Howard, Michael J. Mendenhall, Gilbert L. Peterson

Faculty Publications

The spectral-spatial relationship of materials in a hyperspectral image cube is exploited to partially automate the creation of Geographic Information System (GIS) layers. The topological neighborhood preservation property of the Self Organizing Map (SOM) is clustered into six (partially overlapping) neighborhoods that are mapped into the image domain to locate in-scene structures of similar material type. GIS layers are abstracted through spatial logical and morphological operations on the six image domain material maps and a novel road finding algorithm connects road segments under significant tree-occlusion resulting in a contiguous road network. It is assumed that specific knowledge of the scene …

Robust Unconstrained Face Detection And Lip Localization Using Gabor Filters, Robert E. Hursig

Master's Theses

Automatic speech recognition (ASR) is a well-researched field of study aimed at augmenting the man-machine interface through interpretation of the spoken word. From in-car voice recognition systems to automated telephone directories, automatic speech recognition technology is becoming increasingly abundant in today’s technological world. Nonetheless, traditional audio-only ASR system performance degrades when employed in noisy environments such as moving vehicles. To improve system performance under these conditions, visual speech information can be incorporated into the ASR system, yielding what is known as audio-video speech recognition (AVASR). A majority of AVASR research focuses on lip parameters extraction within controlled environments, but these …

Diffusion And Fractional Diffusion Based Image Processing, Jonathan Blackledge

Conference papers

We consider the background to describing strong scattering in terms of diffusive processes based on the diffusion equation. Intermediate strength scattering is then considered in terms of a fractional diffusion equation which is studied using results from fractional calculus. This approach is justified in terms of the generalization of a random walk model with no statistical bias in the phase to a random walk that has a phase bias and is thus, only ‘partially’ or ‘fractionally’ diffusive. A Green’s function solution to the fractional diffusion equation is studied and a result derived that provides a model for an incoherent image …

Inverse Scattering Solutions For Side-Band Signals, Jonathan Blackledge, Timo Hamalainen, Jyrki Joutsensalo

Conference papers

When a signal is recorded that has been physically generated by some scattering process (the interaction of electromagnetic waves with an inhomogeneous dielectric, for example), the `standard model' for the signal (i.e. information content convolved with a characteristic Impulse Response Function) is usually based on a single scattering approximation. An additive noise term is introduced into the model to take into account a range of non-deterministic factors including multiple scattering that, along with electronic noise and other background noise sources, is assumed to be relatively weak. Thus, the standard model is based on a `weak field condition' and the inverse …

A Graph-Based Approach To Symbolic Functional Decomposition Of Finite State Machines, Piotr Szotkowski, Mariusz Rawski, Henry Selvaraj

Electrical & Computer Engineering Faculty Research

This paper discusses the symbolic functional decomposition method for implementing finite state machines in field-programmable gate array devices. This method is a viable alternative to the presently widespread two-step approaches to the problem, which consist of separate encoding and mapping stages; the proposed method does not have a separate decomposition step instead, the state's final encoding is introduced gradually on every decomposition iteration. Along with general description of the functional symbolic decomposition method's steps, the paper discusses various algorithms implementing the method and presents an example realisation of the most interesting algorithm. In the end, the paper compares the results …

An Approach Based On Wavelet Decomposition And Neural Network For Ecg Noise Reduction, Suranai Poungponsri

Master's Theses

Electrocardiogram (ECG) signal processing has been the subject of intense research in the past years, due to its strategic place in the detection of several cardiac pathologies. However, ECG signal is frequently corrupted with different types of noises such as 60Hz power line interference, baseline drift, electrode movement and motion artifact, etc. In this thesis, a hybrid two-stage model based on the combination of wavelet decomposition and artificial neural network is proposed for ECG noise reduction based on excellent localization features: wavelet transform and the adaptive learning ability of neural network. Results from the simulations validate the effectiveness of this …

Time-Frequency Analysis Of Intracardiac Electrogram, Erik Brockman

Master's Theses

The Cardiac Rhythm Management Division of St. Jude Medical specializes in the development of implantable cardioverter defibrillators that improve the quality of life for patients diagnosed with a variety of cardiac arrhythmias, especially for patients prone to sudden cardiac death. With the goal to improve detection of cardiac arrhythmias, this study explored the value in time-frequency analysis of intracardiac electrogram in four steps. The first two steps characterized, in the frequency domain, the waveforms that construct the cardiac cycle. The third step developed a new algorithm that putatively provides the least computationally expensive way to identifying cardiac waveforms in the …

Probability Density Functions For Snir In Ds-Cdma, David W. Matolak

Faculty Publications

Analytical expressions for the probability density function of block-wise signal-to-noise-plus-interference ratio for both synchronous and asynchronous direct-sequence spread spectrum code-division multiple access systems are developed, for equal average energy signals on the Gaussian and Rayleigh flat fading channels. Using the standard Gaussian approximation for multi-user interference, accurate density approximations are obtained, which agree very well with computer simulation results.

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 …

Proceedings Of The Scientific Conference On Energy And It At Alvsjo Fair, Stockholm March 11-12, 2009 In Connection With The “Energitinget 2009, Dr. Erik Dahlquist, Dr. Jenny Palm

Dr. Erik Dahlquist

This book contains the proceedings from the Energy and IT conference at Alvsjo Energy conference "Energitinget" arranged by Swedish Energy Agency, with approximately 2500 visitors. The papers contain both technical and social science papers, relating to both energy efficiency in buildings and in industry.

An Adaptive Adjacent Channel Interference Cancellation Technique, Robert H. Morelos-Zaragoza, Shobha Kuruba

Robert Henry Morelos-Zaragoza

In this paper, an adaptive adjacent channel interference (ACI) technique is proposed. Results for BPSK modulation with rectangular and square-root raised-cosine pulse shaping, under AWGN conditions, are obtained showing the proposed method to be effective in improving performance under high levels of interference. Basically, the idea is to send pilot signals and then to use them in estimating the amount of ACI in the frequency domain. The estimated spectral error is used to modify tap weights of an adaptive frequency-domain filter. Our simulation results reported suggest that ACI can be effectively reduced with the proposed technique. At the system level, …

Low Power Fft Processor Design Considerations For Ofdm Communications, David Layne Rushforth

UNLV Theses, Dissertations, Professional Papers, and Capstones

Today's emerging communication technologies require fast processing as well as efficient use of resources. This project specifically addresses the power-efficient design of an FFT processor as it relates to OFDM communications such as cognitive radio. The Fast Fourier Transform (FFT) processor is what enables the efficient modulation in OFDM. As the FFT processor is the most computationally intensive component in OFDM communication, the power efficiency improvement of this component can have great impacts on the overall system. These impacts are significant considering the number of mobile and remote communication devices that rely on limited battery-powered operation. This project explores current …

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 …

Human Identification Using Pyroelectric Infrared Sensors, Aron E. Suppes

UNLV Theses, Dissertations, Professional Papers, and Capstones

The objective of this thesis is to discuss the viability of using pyroelectric infrared (PIR) sensors as a biometric system for human identification.

The human body emits infrared radiation, the distribution of which varies throughout the body, and depends upon the shape and composition of the particular body part. A PIR sensor utilizing a Fresnel lens will respond to this infrared radiation. When a human walks, the motion of the body's individual components form a characteristic gait that is likely to affect a PIR sensor field in a unique way.

A statistical model, such as a Hidden Markov Model, could …

Optimal Distributed Microphone Phase Estimation, Marek B. Trawicki, Michael T. Johnson

Dr. Dolittle Project: A Framework for Classification and Understanding of Animal Vocalizations

This paper presents a minimum mean-square error spectral phase estimator for speech enhancement in the distributed multiple microphone scenario. The estimator uses Gaussian models for both the speech and noise priors under the assumption of a diffuse incoherent noise field representing ambient noise in a widely dispersed microphone configuration. Experiments demonstrate significant benefits of using the optimal multichannel phase estimator as compared to the noisy phase of a reference channel.

Auditory Coding Based Speech Enhancement, Yao Ren, Michael T. Johnson

Dr. Dolittle Project: A Framework for Classification and Understanding of Animal Vocalizations

This paper demonstrates a speech enhancement system based on an efficient auditory coding approach, coding of time-relative structure using spikes. The spike coding method can more compactly represent the non-stationary characteristics of speech signals than the Fourier transform or wavelet transform. Enhancement is accomplished through the use of MMSE thresholding on the spike code. Experimental results show that compared with the spectral domain logSTSA filter, both the subjective spectrogram evaluation and objective SSNR improvement for the proposed approach is better in suppressing noise in high noise situations, with fewer musical artifacts.P

Changes And Challenges In Uncertain Times: When The Only Constant Is Change

ACUTA: Other Publications

The Forums

Since 1997, the annual ACUTA Forum for Strategic Leadership in Information Communications Technology has provided a unique for campus leaders to exchange ideas and discuss issues relevant to the use technology in meeting the goals of higher education. Held in conjunction with ACUTA's Annual Conference and Exhibition, this forum brings together men and women of vision, foresight, and authority to discuss strategic directions for the campus of the future.

Goals

• To provide a venue for the examination of issues and challenges facing the higher education community as we grapple with planning, financing, and implementing technology on our campuses. …

Frequency Diversity For Improving Synthetic Aperture Radar Imaging, Jawad L. Farooq

Theses and Dissertations

In this work, a novel theoretical framework is presented for using recent advances in frequency diversity arrays (FDAs). Unlike a conventional array, the FDA simultaneously transmits a unique frequency from each element in the array. As a result, special time and space properties of the radiation pattern are exploited to improve cross-range resolution. The idealized FDA radiation pattern is compared with and validated against a full-wave electromagnetic solver, and it is shown that the conventional array is a special case of the FDA. A new signal model, based on the FDA, is used to simulate SAR imagery of ideal point …