Signal Processing Commons^™

Touch Screen Sound Controller, James Fenley, Jonathan Law

Electrical Engineering

The Touch Screen Sound Controller sets out to explore the use of a touch screen as a sound control interface for the disk jockey profession. In addition, the project aims to provide an alternate means of transferring audio data by way of TCP/IP communications as opposed to MIDI. By applying our method, a user may stream pulse-code modulated data from a server onto a client’s RAM via an Ethernet connection. A 32bit, 200MHz ARM9 microprocessor addresses data from the RAM and proceeds with executing DSP instructions from the user. The connection between the touch screen and the central microprocessor is …

Ultrasonic Shark-Tag Locator System For Iver2 Auv, Nathaniel Garcia

Computer Engineering

The purpose of this project is to develop a system for tracking an ultrasonic underwater transmitter that can be integrated into an IVER2 AUV to allow it to follow and monitor tagged sharks in the ocean for scientific research.

The system consists of a four main components including a shark-tag, two hydrophones, a filter/amplifier & threshold detector circuit, and a microcontroller.

This project, while not completing field testing and integration with the IVER2, is a proof of concept of a system that utilizes passive sonar to determine a bearing from the system to a shark-tag transmitter. Additionally, it devised several …

Information Hiding Using Stochastic Diffusion For The Covert Transmission Of Encrypted Images, Jonathan Blackledge

Conference papers

A principal weakness of all encryption systems is that the output data can be `seen' to be encrypted. In other words, encrypted data provides a 'flag' on the potential value of the information that has been encrypted. In this paper, we provide a novel approach to `hiding' encrypted data in a digital image. We consider an approach in which a plaintext image is encrypted with a cipher using the processes of `stochastic diffusion' and the output quantized into a 1-bit array generating a binary image cipher-text. This output is then `embedded' in a host image which is undertaken either in …

Ultrasonic Listener: Microcontroller Based Frequency Shifter, Troy Fredriks

Electrical Engineering

No abstract provided.

Stochastic Feature Selection With Distributed Feature Spacing For Hyperspectral Data, Jeffrey D. Clark, Michael J. Mendenhall, Gilbert L. Peterson

Faculty Publications

Feature subset selection is a well studied problem in machine learning. One short-coming of many methods is the selection of highly correlated features; a characteristic of hyperspectral data. A novel stochastic feature selection method with three major components is presented. First, we present an optimized feature selection method that maximizes a heuristic using a simulated annealing search which increases the chance of avoiding locally optimum solutions. Second, we exploit local cross correlation pair-wise amongst classes of interest to select suitable features for class discrimination. Third, we adopt the concept of distributed spacing from the multi-objective optimization community to distribute features …

A Locally Adaptable Iterative Rx Detector, Yuri P. Taitano, Brian G. Geier, Kenneth W. Bauer

Faculty Publications

We present an unsupervised anomaly detection method for hyperspectral imagery (HSI) based on data characteristics inherit in HSI. A locally adaptive technique of iteratively refining the well-known RX detector (LAIRX) is developed. The technique is motivated by the need for better first- and second-order statistic estimation via avoidance of anomaly presence. Overall, experiments show favorable Receiver Operating Characteristic (ROC) curves when compared to a global anomaly detector based upon the Support Vector Data Description (SVDD) algorithm, the conventional RX detector, and decomposed versions of the LAIRX detector. Furthermore, the utilization of parallel and distributed processing allows fast processing time making …

An Investigation Of Wavelets, Wendy Bergh

Honors Capstones

Capstone submitted as a graduation requirement for the BSU Honors Program.

Embedding Gps Data Into Speech Signal, Kagan Can

Electrical & Computer Engineering Theses & Dissertations

Communication between deployed troops is very important on a battlefield. The real time knowledge of the location of the communicating patter is also very important in many situations because if you do not know the exact position of your units you cannot give correct orders. A minor error in an order can cause fatal results or lead to defeat. In many cases the position of the units is given through the speech channel by simply speaking the coordinates of the location. This can cause misunderstandings due to misinterpretation of the speech and makes it unsafe to rely on such communications. …

A Novel Digital Audio Watermarking Approach By Embedding Coefficients In Discrete Cosine Transform Domain, Erol Duymaz

Electrical & Computer Engineering Theses & Dissertations

Watermarking is a basic secure communication method. It is used for embedding a recognizable pattern in media in such a manner that modification of the media also modifies the pattern, thus making it easy to detect the modification. This technique and its variants have many practical applications pertaining to secure communications, media verification, etc. Digital audio watermarking is a technique for embedding data within an audio signal in such a way that the original and the modified audio signals are essentially identical. The embedded data can be used for various purposes such as secure communication in military applications, owner identification …

Space-Time Adaptive Processing With Multi-Staged Wiener Filter And Principal Component Signal Dependent Algorithms, Zheng N. Zhou

Master's Theses

Space-time Adaptive Processing (STAP) is a two-dimensional filtering technique for antenna array with multiple spatial channels. The name "space-time" describes the coupling of these spatial channels with pulse-Doppler waveforms. Applications for STAP includes ground moving target indicator (GMTI) for airborne radar systems.

Today, there are strong interests to develop STAP algorithms for operations in “sample starved” environments, where intense environmental interference can reduce STAP capacity to detect and track ground targets. Careful applications of STAP can effectively overcome these conditions by suppressing these interferences and maximize the signal to interference plus noise ratio (SINR). The Multi-stage Wiener filter (MWF) and …

Measuring Variations Of Mimicry By Means Of Prosodic Cues In Task-Based Scenarios And Conversational Speech, Brian Vaughan, Celine De Looze

Other resources

Here, we address the measurement of mimicry, that is when speakers’ speech variations look like parallel patterns.

As a definition of mimicry, we often read in the literature description such as mimicry is “The situation where the observed behaviours of two inter-actants although dissimilar at the start of the interaction are moving towards behavioral matching”. These types of descriptions imply that mimicry is a linear phenomenon and that speakers tend to imitate over time. However, it can be assumed, especially when studying spontaneous speech, that there are rather phases of mimicry and non-mimicry and that mimicry should be rather …

Spectrally-Temporally Adapted Spectrally Modulated Spectrally Encoded (Smse) Waveform Design For Coexistent Cr-Based Sdr Applications, Eric C. Like

Theses and Dissertations

This work expands the applicability of the Spectrally Modulated, Spectrally Encoded (SMSE) framework by developing a waveform optimization process that enables intelligent waveform design. The resultant waveforms are capable of adapting to a spectrally diverse transmission channel while meeting coexistent constraints. SMSE waveform design is investigated with respect to two different forms of coexisting signal constraints, including those based on resultant interference levels and those based on resultant power spectrum shape. As demonstrated, the SMSE framework is well-suited for waveform optimization given its ability to allow independent design of spectral parameters. This utility is greatly enhanced when soft decision selection …

Effects Of Channel Mismatches On Beamforming And Signal Detection, Christopher I. Allen

Theses and Dissertations

Tuner gain measurements of a multichannel receiver are reported. A linear regression model is used to characterize the gain, as a function of channel number, tuner set-on frequency, and intermediate frequency. Residual errors of this model are characterized by a t distribution. Very strong autocorrelation of tuner gain at various frequencies is noted. Tuner performance from one channel to the next is diverse; several defects at specific frequencies are noted. The Wilcoxon signed rank test is used to test normality of tuner gain among devices; normality is rejected. Antenna directivity and phase pattern measurements are also reported. An antenna element …

Pulse Shape Correlation For Laser Detection And Ranging (Ladar), Brian T. Deas

Theses and Dissertations

Radar systems provide an important remote sensing capability, and are crucial to the layered sensing vision; a concept of operation that aims to apply the right number of the right types of sensors, in the right places, at the right times for superior battle space situational awareness. The layered sensing vision poses a range of technical challenges, including radar, that are yet to be addressed. To address the radar-specific design challenges, the research community responded with waveform diversity; a relatively new field of study which aims reduce the cost of remote sensing while improving performance. Early work suggests that the …

An Approach To Large Scale Radar-Based Modeling And Simulation, Lester C. Long Iv

Theses and Dissertations

This research presents a method of aggregating, or reducing the resolution, of a commonly available Department of Defense (DoD) simulation. It addresses the differences between varying levels of resolution and scope used in the DoD’s hierarchy of models pyramid. A data representation that aggregates engagement-level simulation data to use at a lower resolution level, the mission-level, is presented and analyzed. Two formats of implementing this data representation are developed and compared: the rigid cylinder format and the expanding tables format. The rigid cylinder format provides an intuitive way to visualize the data and is used to develop the theory. The …

The Effect Of Synthetic Aperture Radar Image Resolution On Target Discrimination, John E. Mcgowan

Theses and Dissertations

This research details the effect of spatial resolution on target discrimination in Synthetic Aperture Radar (SAR) images. Multiple SAR image chips containing targets and non-targets are used to test a baseline Automatic Target Recognition (ATR) system with reduced spatial resolution. Spatial resolution is reduced by lowering the pixel count or synthesizing a degraded image by filtering and reducing the pixel count. A two-parameter Constant False Alarm Rate (CFAR) detector is tested, and three feature sets, size, contrast, and texture, are used to train a linear classifier and to estimate probability density functions for the two classes. The results are scored …

Development And Evaluation Of A Multistatic Ultrawideband Random Noise Radar, Matthew E. Nelms

Theses and Dissertations

This research studies the AFIT noise network (NoNET) radar node design and the feasibility in processing the bistatic channel information of a cluster of widely distributed noise radar nodes. A system characterization is used to predict theoretical localization performance metrics. Design and integration of a distributed and central signal and data processing architecture enables the Matlab®-driven signal data acquisition, digital processing and multi-sensor image fusion. Experimental evaluation of the monostatic localization performance reveals its range measurement error standard deviation is 4.8 cm with a range resolution of 87.2(±5.9) cm. The 16-channel multistatic solution results in a 2-dimensional localization error of …

Design Of A Monocular Multi-Spectral Skin Detection, Melanin Estimation, And False-Alarm Suppression System, Keith R. Peskosky

Theses and Dissertations

A real-time skin detection, false-alarm reduction, and melanin estimation system is designed targeting search and rescue (SAR) with application to special operations for manhunting and human measurement and signatures intelligence. A mathematical model of the system is developed and used to determine how the physical system performs under illumination, target-to-sensor distance, and target-type scenarios. This aspect is important to the SAR community to gain an understanding of the deployability in different operating environments. A multi-spectral approach is developed and consists of two short-wave infrared cameras and two visible cameras. Through an optical chain of lenses, custom designed and fabricated dichroic …

Aiding Gps With Additional Satellite Navigation Services, Yasin A. Mutlu

Theses and Dissertations

In modern warfare navigation services are very important. GPS is currently providing service for accurate navigation, except in some areas, especially urban areas, where GPS signals cannot always be tracked by users. In these cases some additional navigation support could be provided by other global navigation satellite systems. If GPS is combined with other navigation systems than the navigation gap will be minor. In this thesis, the effect of combining GPS with other satellite navigation systems, specifically GLONASS, Galileo and Compass, is evaluated in terms of availability and position dilution of precision (PDOP) values. First, satellite constellations are simulated in …

Digital Delay Device, Guna Seetharaman, Paul E. Kladitis

AFIT Patents

A digitally controlled optical delay apparatus providing optical signal delays electrically selectable in the picosecond to nanosecond range by way of selectable signal path lengths. Path lengths are incremented in physical length and path delay time according to digital ratios. The delay element includes micro-miniature path changing mirrors controlled in path length selecting positioning by input signals of logic level magnitude. Fiber optic coupling of signals to and from the delay element and a combination of fixed position and movable mirror included optical signal path lengths are included.