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Virtual Reality Engine Development, Varun Varahamurthy 2014 California Polytechnic State University, San Luis Obispo

Virtual Reality Engine Development, Varun Varahamurthy

Master's Theses

With the advent of modern graphics and computing hardware and cheaper sensor and display technologies, virtual reality is becoming increasingly popular in the fields of gaming, therapy, training and visualization. Earlier attempts at popularizing VR technology were plagued by issues of cost, portability and marketability to the general public. Modern screen technologies make it possible to produce cheap, light head-mounted displays (HMDs) like the Oculus Rift, and modern GPUs make it possible to create and deliver a seamless real-time 3D experience to the user. 3D sensing has found an application in virtual and augmented reality as well, allowing for a …


Atrengine: An Orientation-Based Algorithm For Automatic Target Recognition, Justin Ting-Jeuan Kuo 2014 California Polytechnic State University, San Luis Obispo

Atrengine: An Orientation-Based Algorithm For Automatic Target Recognition, Justin Ting-Jeuan Kuo

Master's Theses

Automatic Target Recognition (ATR) is a subject involving the use of sensor data to develop an algorithm for identifying targets of significance. It is of particular interest in military applications such as unmanned aerial vehicles and missile tracking systems. This thesis develops an orientation-based classification approach from previous ATR algorithms for 2-D Synthetic Aperture Radar (SAR) images. Prior work in ATR includes Chessa Guilas’ Hausdorff Probabilistic Feature Analysis Approach in 2005 and Daniel Cary’s Optimal Rectangular Fit in 2007.

A system incorporating multiple modules performing different tasks is developed to streamline the data processing of previous algorithms. Using images from …


A Comparison Of Image Processing Techniques For Bird Detection, Elsa Reyes 2014 California Polytechnic State University, San Luis Obispo

A Comparison Of Image Processing Techniques For Bird Detection, Elsa Reyes

Master's Theses

Orchard fruits and vegetable crops are vulnerable to wild birds and animals. These wild birds and animals can cause critical damage to the produce. Traditional methods of scaring away birds such as scarecrows are not long-term solutions but short-term solutions. This is a huge problem especially near areas like San Luis Obispo where there are vineyards. Bird damage can be as high as 50% for grapes being grown in vineyards. The total estimated revenue lost annually in the 10 counties in California due to bird and rodent damage to 22 selected crops ranged from $168 million to $504 million (in …


An Eigenvector-Based Test For Local Stationarity Applied To Array Processing, Jorge Quijano, Lisa M. Zurk 2014 Portland State University

An Eigenvector-Based Test For Local Stationarity Applied To Array Processing, Jorge Quijano, Lisa M. Zurk

Electrical and Computer Engineering Faculty Publications and Presentations

In sonar array processing, a challenging problem is the estimation of the data covariance matrix in the presence of moving targets in the water column, since the time interval of data local stationarity is limited. This work describes an eigenvector-based method for proper data segmentation into intervals that exhibit local stationarity, providing data-driven higher bounds for the number of snapshots available for computation of time-varying sample covariance matrices. Application of the test is illustrated with simulated data in a horizontal array for the detection of a quiet source in the presence of a loud interferer.


A Frequency-Domain Method For Active Acoustic Cancellation Of Known Audio Sources, Ryan D. Rocha 2014 California Polytechnic State University, San Luis Obispo

A Frequency-Domain Method For Active Acoustic Cancellation Of Known Audio Sources, Ryan D. Rocha

Master's Theses

Active noise control (ANC) is a real-time process in which a system measures an external, unwanted sound source and produces a canceling waveform. The cancellation is due to destructive interference by a perfect copy of the received signal phase-shifted by 180 degrees. Existing active noise control systems process the incoming and outgoing audio on a sample-by-sample basis, requiring a high-speed digital signal processor (DSP) and analog-to-digital converters (ADCs) with strict timing requirements on the order of tens of microseconds. These timing requirements determine the maximum sample rate and bit size as well as the maximum attenuation that the system can …


Crotale Sample Library, Ryan Waczek 2014 California Polytechnic State University - San Luis Obispo

Crotale Sample Library, Ryan Waczek

Music

This report will discuss the process of creating a digital sample based library for musical applications. Topics such as recording, microphone placement, and mixing will be addressed; as well as elements of design in Adobe Photoshop, and computer scripting in the language of the computer program Komplete 5 by Native Instruments. The instrument sampled is the crotales, an orchestral, melodic percussion instrument.


Low Voltage Cmos Sar Adc Design, Ryan Hunt 2014 California Polytechnic State University - San Luis Obispo

Low Voltage Cmos Sar Adc Design, Ryan Hunt

Electrical Engineering

This project centers on the design of a single ended 10-bit successive approximation register analog to digital converter (SAR ADC for short) that easily interfaces to a micro-controller, such as an Arduino. With micro-controller interfacing in mind, the universal data transfer technique of SPI proved an easy way to communicate between the ADC and the micro-controller. The ADC has a range of 1V (highest code value) to 0V (lowest code value) and operates from a single voltage rail value of 1.8V. Typical SPI clock speeds run on the order of 2MHz and with a 10-bit ADC this means a sampling …


Real Time Swim Instructor, Konrad Antoniuk 2014 California Polytechnic State University - San Luis Obispo

Real Time Swim Instructor, Konrad Antoniuk

Electrical Engineering

Both competitive and recreational swimmers want an efficient swim stroke but often lack consistent feedback with technical insight. Competitive swimmers rely on coaches for instruction but have to stop swimming to listen. The Real Time Swim Instructor project provides live feedback to a swimmer so they can feel their stroke correction while they’re swimming. The developing swimmer feels the difference between correct and incorrect form instantaneously.

The project takes on the responsibility of measuring the moving body, accurately determining stroke improvement, functioning under water, and providing recognizable feedback. Additionally, the user can review their swim from data stored in memory. …


Power System Fault Detection Using The Discrete Wavelet Transform And Artificial Neural Networks, Kevin Keegan 2014 California Polytechnic State University - San Luis Obispo

Power System Fault Detection Using The Discrete Wavelet Transform And Artificial Neural Networks, Kevin Keegan

Electrical Engineering

This project focuses on detecting various phase to ground faults in three phase power systems. In this research, the faults are generated using a power distribution system simulator; and the three phase voltage waveforms are analyzed using the discrete wavelet transform. Multi-layer feed forward neural networks are employed for fault detection and classification. The effectiveness of this approach is demonstrated by computer simulation results.


Variable Precision Tandem Analog-To-Digital Converter (Adc), Colton A. Parsons 2014 California Polytechnic State University, San Luis Obispo

Variable Precision Tandem Analog-To-Digital Converter (Adc), Colton A. Parsons

Master's Theses

This paper describes an analog-to-digital signal converter which varies its precision as a function of input slew rate (maximum signal rate of change), in order to best follow the input in real time. It uses Flash and Successive Approximation (SAR) conversion techniques in sequence.

As part of the design, the concept of "total real-time optimization" is explored, where any delay at all is treated as an error (Error = Delay * Signal Slew Rate). This error metric is proposed for use in digital control systems. The ADC uses a 4-bit Flash converter in tandem with SAR logic that has variable …


Transmission Of Stereo Audio Signals With Lasers, William Austin Curbow 2014 University of Arkansas, Fayetteville

Transmission Of Stereo Audio Signals With Lasers, William Austin Curbow

Electrical Engineering Undergraduate Honors Theses

An alternative method for transmitting audio signals via the use of laser technology was presented here. The primary focus of this document is on the audio amplifier subsystem including the design, simulation, and performance results. Simulations using the PSPICE computer simulation software were utilized to investigate the theoretical designs of the audio amplifier subsystem. The audio amplifier was examined in three junctures including the noise-canceling input stage, the high voltage gain cell, and the low impedance driver. Through the design procedure using theoretical calculations, simulations using PSPICE computer software, and examination of the finished product with an oscilloscope, the audio …


On Uniformly Most Powerful Decentralized Detection, Uri Rogers 2014 Boise State University

On Uniformly Most Powerful Decentralized Detection, Uri Rogers

Boise State University Theses and Dissertations

The theory behind Uniformly Most Powerful (UMP) composite binary hypothesis testing is mature and well defined in centralized detection where all observations are directly accessible at one central node. However, within the area of decentralized detection, UMP tests have not been researched, even though tests of this nature have properties that are highly desirable. The purpose of this research is to extend the UMP concept into decentralized detection, which we define as UMP decentralized detection (UMP-DD). First, the standard parallel decentralized detection model with conditionally independent observations will be explored. This section will introduce theorems and corollaries that define when …


Multiframe Adaptive Wiener Filter Super-Resolution With Jpeg2000-Compressed Images, Barath Narayanan Narayanan, Russell C. Hardie, Eric J. Balster 2014 University of Dayton

Multiframe Adaptive Wiener Filter Super-Resolution With Jpeg2000-Compressed Images, Barath Narayanan Narayanan, Russell C. Hardie, Eric J. Balster

Electrical and Computer Engineering Faculty Publications

Historically, Joint Photographic Experts Group 2000 (JPEG2000) image compression and multiframe super-resolution (SR) image processing techniques have evolved separately. In this paper, we propose and compare novel processing architectures for applying multiframe SR with JPEG2000 compression. We propose a modified adaptive Wiener filter (AWF) SR method and study its performance as JPEG2000 is incorporated in different ways. In particular, we perform compression prior to SR and compare this to compression after SR. We also compare both independent-frame compression and difference-frame compression approaches. We find that some of the SR artifacts that result from compression can be reduced by decreasing the …


An Adaptive Kalman Filter For Voltage Sag Detection In Power Systems, Hisham Odeh Alrawashdeh 2014 Western Michigan University

An Adaptive Kalman Filter For Voltage Sag Detection In Power Systems, Hisham Odeh Alrawashdeh

Dissertations

The exact values of the noise covariance matrix of the Kalman filter state vector Q and the measured signal noise covariance matrix R must be obtained in order to achieve the optimal performance of the Kalman filter. There have been many techniques and assumptions made to evaluate and compute Q and R. The effects of Q and R are investigated in detail in this dissertation. Based on these investigations, the Kalman filter has been modeled to detect the fundamental signal amplitude variations of power system signals. This technique helps in evaluating voltage sags in power systems.

Two algorithms are …


Studies In Software-Defined Radio System Implementation, Harold A. Haldren III 2014 Liberty University

Studies In Software-Defined Radio System Implementation, Harold A. Haldren Iii

Senior Honors Theses

Over the past decade, software-defined radios (SDRs) have an increasingly prevalent aspect of wireless communication systems. Different than traditional hardware radios which implement radio protocols using static electrical circuit, SDRs implement significant aspects of physical radio protocol using software programs running on a host processor. Because they use software to implement most of the radio functionality, SDRs are much more easily modified, edited, and upgraded than their hardware-defined counterparts. Consequently, researchers and developers have been developing previously hardware-defined radio systems within software. Thus, communication standards can be tested under different conditions or swapped out entirely by simply changing some code. …


Large-Scale Site And Frequency Diversity In Urban Peer-To-Peer Channels For Six Public Safety Frequency Bands, David W. Matolak, Kate A. Remley, Christopher L. Holloway, Qian Zhang, Qiong Wu 2014 University of South Carolina - Columbia

Large-Scale Site And Frequency Diversity In Urban Peer-To-Peer Channels For Six Public Safety Frequency Bands, David W. Matolak, Kate A. Remley, Christopher L. Holloway, Qian Zhang, Qiong Wu

Faculty Publications

We report on peer-to-peer large-scale wireless channel characteristics for an urban environment in six public-safety bands, for five simultaneous receiving sites. Results are based upon measurements taken in Denver in July 2009 with stationary receivers and a pedestrian transmitter. The six frequencies at which we measured are (in MHz) 430, 750, 905, 1834, 2400, and 4860. We quantify both site and frequency diversity, and show that 5-site selection yields minimum average gains of 15 dB in mean received power levels; 5-site selection diversity also reduces received power variation by 17-29 dB, depending on frequency. Frequency diversity yields similar gains. By …


Removing Parallax-Induced False Changes In Change Detection, Karmon M. Vongsy 2014 Air Force Institute of Technology

Removing Parallax-Induced False Changes In Change Detection, Karmon M. Vongsy

Theses and Dissertations

Accurate change detection (CD) results in urban environments is of interest to a diverse set of applications including military surveillance, environmental monitoring, and urban development. This work presents a hyperspectral CD (HSCD) framework. The framework uncovers the need for HSCD methods that resolve false change caused by image parallax. A Generalized Likelihood Ratio Test (GLRT) statistic for HSCD is developed that accommodates unknown mis-registration between imagery described by a prior probability density function for the spatial mis-registration. The potential of the derived method to incorporate more complex signal proccessing functions is demonstrated by the incorporation of a parallax error mitigation …


Gps Multipath Reduction With Correlator Beamforming, Jason M. Barhorst 2014 Air Force Institute of Technology

Gps Multipath Reduction With Correlator Beamforming, Jason M. Barhorst

Theses and Dissertations

This research effort investigates the feasibility of beamforming using a single Global Positioning System (GPS) front end. Traditional methods of beamforming use multiple front ends, typically one per antenna element. By enabling a receiver to sample a switched antenna array, the hardware cost of implementing a GPS antenna array can be significantly reduced. Similar techniques of reducing the number of receivers have been used by Locata Corporation in the design of their non-GPS positioning systems. However, Locata Corporation's local transmitters provide a signal strength much higher than GPS's signal strength. For this reason, the inclusion of low-noise amplifiers into the …


The Garage Band Lightshow, Jason DeScenzo 2014 California Polytechnic State University - San Luis Obispo

The Garage Band Lightshow, Jason Descenzo

Electrical Engineering

The expenses musicians accrue make it hard to afford all the different equipment needed to perform and very unlikely that the average start up band or artist can afford the luxury of a musical light show in their early performances. The Garage Band Lightshow provides an easily set up and affordable way for musicians to use concert lighting in their performances. The Garage Band Lightshow provides one LED box. The light box responds to an audio signal and provides varying pulses and colors of light depending on the high, mid, and low frequencies of the audio signal. The Garage Band …


An Experimental Evaluation Of Image Quality For Various Scenarios In A Chromotomographic System With A Spinning Prism, Kyle J. Dufaud 2014 Air Force Institute of Technology

An Experimental Evaluation Of Image Quality For Various Scenarios In A Chromotomographic System With A Spinning Prism, Kyle J. Dufaud

Theses and Dissertations

A lab and eld based hyperspectral chromotomographic imager has been developed at the Air Force Institute of Technology. It is a prototype used to study the requirements for a space-based system. The imager uses a high speed visible band camera behind a direct-vision prism to image both spatial dimensions and the spectral dimension at the same time. Capturing all 3 simultaneously allows for the hyperspectral imaging of transient events. The prism multiplexes the spectral and spatial information, so tomographic reconstruction algorithms must be used to separate hyperspectral channels. Experiments were conducted to compare reconstructed image quality as a function of …


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