Signal Processing Commons^™

Navigation And Position Determination With A Multicarrier Modulation Signal Of Opportunity, Richard K. Martin, Jamie S. Velotta, John F. Raquet

AFIT Patents

A multicarrier modulation position determination method that includes deploying at least one known receiver with a known location and a second receiver with an unknown location. At least two signals of opportunity with different locations are obtained by both the receiver and the second receiver. The signals having a plurality of block data, the block data having block boundaries. The block boundaries including a beginning block boundary and an end block boundary. The block data further including a cyclic prefix at the beginning block boundary. Acquiring a plurality of data samples for at least a portion of the block data …

Highly Efficient Maximum Power Point Tracking Using A Quasi-Double-Boost Dc/Dc Converter For Photovoltaic Systems, Christopher J. Lohmeier

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Solar photovoltaic (PV) panels are a great source of renewable energy generation. The biggest problem with solar systems is relatively low efficiency and high cost. This work hopes to alleviate this problem by using novel power electronic converter and control designs. An electronic DC/DC converter, called “Quasi-Double-Boost DC/DC Converter,” is designed for a Solar PV system. A Maximum Power Point Tracking (MTTP) algorithm is implemented through this converter. This algorithm allows the PV system to work at its highest efficiency. Different current sensing and sensorless technologies used with the converter for the MPPT algorithm are offered and tested. Design aspects …

Analysis Of Contrast Enhancement Methods For Infrared Images, Sprinkle Christian

Master's Theses

Contrast enhancement techniques are used widely to improve the visual quality of images. The difference in luminance reflected from two adjacent surfaces creates contrast between the surfaces in the image. The greater the contrast, the easier it is to recognize and differentiate objects in an image. Thus object contrast is an important factor in the perception of the visual quality of an image and in its usefulness for object recognition and image analysis applications.

The focus of this thesis is on studying how well different contrast enhancement techniques developed for visible spectrum photographic images work on infrared images; to determine …

Sensing And Transmission Strategies In Wireless Cognitive Radio Systems, Babak Abbasi Bastami

UNLV Theses, Dissertations, Professional Papers, and Capstones

The main challenge in any cognitive radio system is to maximize secondary users throughput while limiting interference imposed on licensed users. In this regard, finding the optimal sensing and transmission timing strategies and accurate sensing techniques are of great importance in a cognitive radio network.

In this thesis, we study a sensing-transmission scheme for secondary user in a cognitive radio system where the secondary user senses every primary channel independently and transmits a signal for a fixed duration if it finds the channel empty and stays idle for another fixed duration if it senses the channel busy. We obtain optimal …

Optimized Hyperspectral Imagery Anomaly Detection Through Robust Parameter Design, Francis M. Mindrup

Theses and Dissertations

Anomaly detection algorithms for hyperspectral imagery (HSI) are an important first step in the analysis chain which can reduce the overall amount of data to be processed. The actual amount of data reduced depends greatly on the accuracy of the anomaly detection algorithm implemented. Most, if not all, anomaly detection algorithms require a user to identify some initial parameters. These parameters (or controls) affect overall algorithm performance. Regardless of the anomaly detector being utilized, algorithm performance is often negatively impacted by uncontrollable noise factors which introduce additional variance into the process. In the case of HSI, the noise variables are …

Targeting Breast Cancer Detection With Communications Technology, Hacer Varol

Theses and Dissertations

Breast cancer continues to be a significant public health problem in the United States: It is the second leading cause of female mortality, and, disturbingly, one out of eight women in the United States will be diagnosed with breast cancer in her life time. Until the cause of this disease is fully understood, early detection remains the only hope to improve prognosis and treatment. In this thesis, the tumor detection problem in breast images is formulated as a hypothesis testing problem, where the signal of interest is the tumor and the noise refers to the healthy tissue in the breast. …

Vibration-Based Health Monitoring Of Multiple-Stage Gear Train And Differential Planetary Transmission Involving Teeth Damage And Backlash Nonlinearity, Andrew Patrick Sommer

Master's Theses

The objective of this thesis is to develop vibration-based fault detection strategies for on-line condition monitoring of gear transmission systems. The study divides the thesis into three sections. First of all, the local stresses created by a root fatigue crack on a pinion spur gear are analyzed using a quasi-static finite element model and non-linear contact mechanics simulation. Backlash between gear teeth which is essential to provide better lubrication on tooth surfaces and to eliminate interference is included as a defect and a necessary part of transmission design. The second section is dedicated to fixed axis power trains. Torsional vibration …

Hyperspectral-Based Adaptive Matched Filter Detector Error As A Function Of Atmospheric Profile Estimation, Allan W. Yarbrough

Theses and Dissertations

Hyperspectral imagery is collected as radiance data. This data is a function of multiple variables: the radiation profile of the light source, the reflectance of the target, and the absorption and scattering profile of the medium through which the radiation travels as it reflects off the target and reaches the imager. Accurate target detection requires that the collected image matches as closely as possible the known "true" target in the classification database. Therefore, the effect of the radiation source and the atmosphere must be removed before detection is attempted. While the spectrum of solar light is relatively stable, the effect …

Constant Conduction Angle Experimental Generation For Rf Power Amplifiers, Michael Spahn

Electrical Engineering

As the demand for more devices to become wireless increases, there is a need for linear, efficient monolithic power amplifiers to deal with the variations in modulation of signals. With partial support from Cal Poly C3RP Grant #52268, this paper explains the implementation of and analyzes a circuit that actively biases a bipolar transistor to operate as a Class C amplifier. The Class C amplifier can maintain constant conduction angle over a range of output powers by using a Class B amplifier to force a scaled DC current vs. input magnitude curve on to a Class C amplifier. The knee …

Face Detection And Lip Localization, Benafsh Nadir Husain

Master's Theses

Integration of audio and video signals for automatic speech recognition has become an important field of study. The Audio-Visual Speech Recognition (AVSR) system is known to have accuracy higher than audio-only or visual-only system. The research focused on the visual front end and has been centered around lip segmentation. Experiments performed for lip feature extraction were mainly done in constrained environment with controlled background noise. In this thesis we focus our attention to a database collected in the environment of a moving car which hampered the quality of the imagery.

We first introduce the concept of illumination compensation, where we …

Cyclostationary Detection For Ofdm In Cognitive Radio Systems, Marcos E. Castro

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Research on cognitive radio systems has attracted much interest in the last 10 years. Cognitive radio is born as a paradigm and since then the idea has seen contribution from technical disciplines under different conceptual layers. Since then improvements on processing capabilities have supported the current achievements and even made possible to move some of them from the research arena to markets.

Cognitive radio implies a revolution that is even asking for changes in current business models, changes at the infrastructure levels, changes in legislation and requiring state of the art technology.

Spectrum sensing is maybe the most important part …

Miniature Mass Spectrometry: Rf Amplitude Control System Design, Matthew Allen Kirleis

Purdue Polytechnic Masters Theses

This thesis covers the methods used to construct and characterize a custom digital RF amplitude control system. Many types of mass spectrometers exist, but few have been miniaturized as much as the Mini instruments developed at Purdue University. The goal of this research was to improve upon an earlier amplitude control system consisting of analog circuits first implemented in the Mini 11.5 mass spectrometer developed at Purdue University.

A custom set of control and data acquisition electronics were developed for testing the digital and analog control systems in a Mini 11.5 mass spectrometer chassis. A MATLAB Simulink simulation was done …

Super-Resolution For Imagery From Integrated Microgrid Polarimeters, Russell C. Hardie, Daniel A. Lemaster, Bradley M. Ratliff

Electrical and Computer Engineering Faculty Publications

Imagery from microgrid polarimeters is obtained by using a mosaic of pixel-wise micropolarizers on a focal plane array (FPA). Each distinct polarization image is obtained by subsampling the full FPA image. Thus, the effective pixel pitch for each polarization channel is increased and the sampling frequency is decreased. As a result, aliasing artifacts from such undersampling can corrupt the true polarization content of the scene. Here we present the first multi-channel multi-frame super-resolution (SR) algorithms designed specifically for the problem of image restoration in microgrid polarization imagers. These SR algorithms can be used to address aliasing and other degradations, without …

Upmixing From Mono : A Source Separation Approach, Derry Fitzgerald

Conference papers

We present a system for upmixing mono recordings to stereo through the use of sound source separation techniques. The use of sound source separation has the advantage of allowing sources to be placed at distinct points in the stereo field, resulting in more natural sounding upmixes. The system separates an input signal into a number of sources, which can then be imported into a digital audio workstation for upmixing to stereo. Considerations to be taken into account when upmixing are discussed, and a brief overview of the various sound source separation techniques used in the system are given. The effectiveness …

Reconfigurable Sampling For Enhanced Energy Efficiency In Power-Constrained Wireless Systems, Timothy Kurp

Master's Theses

Advancement in microelectronics and wireless communications has nurtured the development of low power and low cost wireless systems such as sensor networks. Each node is typically driven by a battery, which has a limited energy capacity that directly constrains node, and network lifetime. This presents a bottleneck for the widespread exploitation of wireless sensing technology. Therefore, improving the energy efficiency of wireless sensing devices is of critical importance and has attracted the attention of the research community.

In this work, a data-driven method has been proposed and systematically investigated. Specifically, this technique reconfigures, in real time, the rate of data …

Characterizing Cyclostationary Features Of Digital Modulated Signals With Empirical Measurements Using Spectral Correlation Function, Mujun Song

Theses and Dissertations

Signal detection is widely used in many applications. Some examples include Cognitive Radio (CR) and military intelligence. CRs use signal detection to sense spectral occupancy. Without guaranteed signal detection, a CR cannot reliably perform its role. Similarly, signal detection is the first step for garnering an opponent's information. Wireless signal detection can be performed using many different techniques. Some of the most popular include matched filters, energy detectors (which use measurements such as the Power Spectral Density (PSD) of the signal), and Cyclostationary Feature Detectors (CFD). Among these techniques, CFD can be viewed as a compromise technique, in that it …

Shifted Nmf Using An Efficient Constant-Q Transform For Monaural Sound Source Separation, Rajesh Jaiswal, Derry Fitzgerald, Eugene Coyle, Scott Rickard

Conference papers

Non-negative Matrix Factorisation (NMF) based algorithms have found application in monaural audio source separation due to their ability to factorize audio spectrogram into additive part-based basis functions, which typically corresponds to individual notes or chords in music. These separated basis functions are usually greater in number than the active sources, hence clustering is needed for individual source signal synthesis. Although, many attempts have been made to improve the clustering of the basis functions to sources, much research is still required in this area. Recently, Shifted NMF based methods have been proposed as a means to avoid clustering these pitched basis …

User Assisted Source Separation Using Non-Negative Matrix Factorisation, Derry Fitzgerald

Conference papers

Much research has been carried out on the use of non-negative matrix factorisation for the purpose of musical sound source separation. However, a notable shortcoming of non-negative matrix factorisation is that the recovered basis functions have to be clustered to sound sources for separation to take place. This has proved to be a difficult problem to solve. As a means of overcoming this problem, we introduce an extension to non-negative matrix factorisation which allows a user to guide the sepa- ration by singing, or playing along with, the source they want to separate. This is done through the use of …

Audio-Triggered El Wire Sequencer, Benjamin (Ben) Paik

Electrical Engineering

“Development of an Audio-Triggered EL Wire Sequencer” California Polytechnic State University 2011, Ben Paik and John Oliver, Ph.D. (advisor)

The purpose of this project is to investigate and develop a method for switching electroluminescent wire (EL wire) such that it can be activated by some audio source.  EL wire is essentially a coaxial capacitor that luminesces when an alternating electric field excites the insulating phosphor layer in the wire (a 100Vp, 1kHz AC source is sufficient for this).   The system involves the EL wire, a six channel sequencer to switch the EL wire, an method for processing the audio signal, …

Rem Sleep Alarm, Shaun Kelsey, Brendon Soltis

Electrical Engineering

This paper explores the REM Sleep Alarm project that deals with the sleep cycle of the average human, and how it affects our ability to function when waking up in the morning.

The purpose of this project is to build a device that has the ability to wake a person up when they will feel the most rested. From research done, it appears that most people feel the most rested when woken up during the REM stage of their sleep cycle. Our goal is to have the device detect when the user is in this stage of sleep, determine how …