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Title: Estimation of the scattering function of fading channels for acoustic communications in shallow waters.
Creator: Allemand, Vincent., Florida Atlantic University, Beaujean, Pierre-Philippe
Abstract/Description: The measurement of the Scattering function of time-variant fading channels is of strong interest in the field of underwater acoustic communications, as it indicates the limitations of the channel capacity. It also helps reducing the development time of acoustic communication systems and the need for on-site tests using so-called "fading simulators". The Scattering function is interpreted as the expected power received at a given time-delay and frequency shift for a given signal transmitted...
Show moreThe measurement of the Scattering function of time-variant fading channels is of strong interest in the field of underwater acoustic communications, as it indicates the limitations of the channel capacity. It also helps reducing the development time of acoustic communication systems and the need for on-site tests using so-called "fading simulators". The Scattering function is interpreted as the expected power received at a given time-delay and frequency shift for a given signal transmitted through the acoustic channel. It has been estimated using a fourth-moment method developed by Kailath from 18 to 30 kHz, 8-ms broad-band chirps and 20--28 kHz, 28-ms pseudo noise sequences. These signals were transmitted periodically in the shallow coastal waters of South Florida from a static source, and recorded from a 64-channel receiver array located at a distance of 1000 meters. Spatial beamforming has been applied to study the spatial sensitivity of the scattering function.
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Date Issued: 2005
PURL: http://purl.flvc.org/fcla/dt/13230
Subject Headings: Underwater acoustic telemetry, Signal processing--Digital techniques, Underwater acoustics--Mathematical models, Adaptive signal processing
Format: Document (PDF)

Title: Underwater laser serial imaging using compressive sensing and digital mirror device.
Creator: Ouyang, Bing, Dalgleish, Fraser R., Caimi, F. M., Giddings, T. E., Shirron, J. J., Vuorenkoski, Anni K., Nootz, G., Britton, W. B., Ramos, Brian
Date Issued: 2011
PURL: http://purl.flvc.org/FCLA/DT/3340793
Subject Headings: Underwater imaging systems, Image compression, Lasers, Signal processing
Format: Document (PDF)

Title: Wavelet de-noising applied to vibrational envelope analysis methods.
Creator: Bertot, Edward Max, Khoshgoftaar, Taghi M., Beaujean, Pierre-Philippe, Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: In the field of machine prognostics, vibration analysis is a proven method for detecting and diagnosing bearing faults in rotating machines. One popular method for interpreting vibration signals is envelope demodulation, which allows a technician to clearly identify an impulsive fault source and its severity. However incipient faults -faults in early stages - are masked by in-band noise, which can make the associated impulses difficult to detect and interpret. In this thesis, Wavelet De...
Show moreIn the field of machine prognostics, vibration analysis is a proven method for detecting and diagnosing bearing faults in rotating machines. One popular method for interpreting vibration signals is envelope demodulation, which allows a technician to clearly identify an impulsive fault source and its severity. However incipient faults -faults in early stages - are masked by in-band noise, which can make the associated impulses difficult to detect and interpret. In this thesis, Wavelet De-Noising (WDN) is implemented after envelope-demodulation to improve accuracy of bearing fault diagnostics. This contrasts the typical approach of de-noising as a preprocessing step. When manually measuring time-domain impulse amplitudes, the algorithm shows varying improvements in Signal-to-Noise Ratio (SNR) relative to background vibrational noise. A frequency-domain measure of SNR agrees with this result.
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Date Issued: 2014
PURL: http://purl.flvc.org/fau/fd/FA00004080, http://purl.flvc.org/fau/fd/FA00004080
Subject Headings: Fluid dynamics, Signal processing, Structural dynamics, Wavelet (Mathematics)
Format: Document (PDF)

Title: Turbo-coded frequency division multiplexing for underwater acoustic communications between 60 kHz and 90 kHz.
Creator: Pajovic, Milutin., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The Intermediate Frequency Acoustic Modem (IFAM), developed by Dr. Beaujean, is designed to transmit the command-and-control messages from the top-side to the wet-side unit in ports and very shallow waters. This research presents the design of the turbo coding scheme and its implementation in the IFAM modem with the purpose of meeting a strict requirement for the IFAM error rate performance. To simulate the coded IFAM, a channel simulator is developed. It is basically a multi-tap filter whose...
Show moreThe Intermediate Frequency Acoustic Modem (IFAM), developed by Dr. Beaujean, is designed to transmit the command-and-control messages from the top-side to the wet-side unit in ports and very shallow waters. This research presents the design of the turbo coding scheme and its implementation in the IFAM modem with the purpose of meeting a strict requirement for the IFAM error rate performance. To simulate the coded IFAM, a channel simulator is developed. It is basically a multi-tap filter whose parameters are set depending on the channel geometry and system specifics. The simulation results show that the turbo code is able to correct 89% of the messages received with errors in the hostile channel conditions. The Bose-Chadhuri-Hocquenghem (BCH) coding scheme corrects less that 15% of these messages. The other simulation results obtained for the system operation in different shallow water settings are presented.
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Date Issued: 2009
PURL: http://purl.flvc.org/FAU/215291
Subject Headings: Underwater acoustics, Measurement, Coding theory, Signal processing, Digital techniques
Format: Document (PDF)

Title: Mobile docking of REMUS-100 equipped with USBL-APS to an unmanned surface vehicle: a performance feasibility study.
Creator: Miranda, Mario II, Beaujean, Pierre-Philippe, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The overall objective of this work is to evaluate the ability of homing and docking an unmanned underwater vehicle (Hydroid REMUS 100 UUV) to a moving unmanned surface vehicle (Wave-Adaptive Modular Surface Vehicle USV) using a Hydroid Digital Ultra-Short Baseline (DUSBL) acoustic positioning system (APS), as a primary navigation source. An understanding of how the UUV can rendezvous with a stationary USV first is presented, then followed by a moving USV. Inherently, the DUSBL-APS is...
Show moreThe overall objective of this work is to evaluate the ability of homing and docking an unmanned underwater vehicle (Hydroid REMUS 100 UUV) to a moving unmanned surface vehicle (Wave-Adaptive Modular Surface Vehicle USV) using a Hydroid Digital Ultra-Short Baseline (DUSBL) acoustic positioning system (APS), as a primary navigation source. An understanding of how the UUV can rendezvous with a stationary USV first is presented, then followed by a moving USV. Inherently, the DUSBL-APS is susceptible to error due to the physical phenomena of the underwater acoustic channel (e.g. ambient noise, attenuation and ray refraction). The development of an APS model has allowed the authors to forecast the UUV’s position and the estimated track line of the USV as determined by the DUSBL acoustic sensor. In this model, focus is placed on three main elements: 1) the acoustic channel and sound ray refraction when propagating in an in-homogeneous medium; 2) the detection component of an ideal DUSBL-APS using the Neyman-Pearson criterion; 3) the signal-to-noise ratio (SNR) and receiver directivity impact on position estimation. The simulation tool is compared against actual open water homing results in terms of the estimated source position between the simulated and the actual USBL range and bearing information.
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Date Issued: 2014
PURL: http://purl.flvc.org/fau/fd/FA00004140, http://purl.flvc.org/fau/fd/FA00004140
Subject Headings: Adaptive signal processing, Mobile robots, Underwater acoustic telemetry
Format: Document (PDF)

Title: Broadband measurements of compressional wave attenuation.
Creator: Reeder, Angela Christine., Florida Atlantic University, Schock, Steven G., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: An in situ acoustic measurement system was developed to estimate the compressional wave attenuation of marine sediments. The system uses acoustic probes to measure a wideband acoustic pulse traveling horizontally though various sediments. The system transmits a 20 millisecond frequency-modulated (FM) pulse swept from 3 to 50 kHz and match filters the received signals. A special ratio of data collected at two horizontal ranges from the source is used to estimate attenuation as a function of...
Show moreAn in situ acoustic measurement system was developed to estimate the compressional wave attenuation of marine sediments. The system uses acoustic probes to measure a wideband acoustic pulse traveling horizontally though various sediments. The system transmits a 20 millisecond frequency-modulated (FM) pulse swept from 3 to 50 kHz and match filters the received signals. A special ratio of data collected at two horizontal ranges from the source is used to estimate attenuation as a function of frequency. Data is collected with the in situ system and a chirp subbottom profiling sonar at two offshore sites to compare the attenuation of horizontally and vertically traveling waves in sediment. The collected data is also used to determine the feasibility of remotely estimating in situ attenuation using a chirp sonar. In situ and chirp sonar estimates agree and fall within the range of attenuation measurements made by other investigators in similar sediments.
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Date Issued: 1996
PURL: http://purl.flvc.org/fcla/dt/15327
Subject Headings: Marine sediments--Acoustic properties--Measurement, Signal processing
Format: Document (PDF)

Title: Design of a frequency shift keying array receiver for the acoustic modem.
Creator: Boubli, Cecile., Florida Atlantic University, LeBlanc, Lester R.
Abstract/Description: Currently, our acoustic modems are used to communicate underwater to Autonomous Underwater Vehicles AUVs. These modems have only one sensor and can transmit at low data rates (from 200 to 1200 bits per second) using Frequency Shift Keying (FSK) modulation. A two-dimensional array receiver (MillsCross) has been developed to receive underwater signals with more reliability, at a higher data rate (about 30,000 bits per second). This array has been designed to operate with Phase Shift Keying...
Show moreCurrently, our acoustic modems are used to communicate underwater to Autonomous Underwater Vehicles AUVs. These modems have only one sensor and can transmit at low data rates (from 200 to 1200 bits per second) using Frequency Shift Keying (FSK) modulation. A two-dimensional array receiver (MillsCross) has been developed to receive underwater signals with more reliability, at a higher data rate (about 30,000 bits per second). This array has been designed to operate with Phase Shift Keying modulated signals. The purpose of this thesis is to design and implement a signal processing software to demodulate and decode FSK signals acquired by the MillsCross. By taking advantage of the spatial gain of the MillsCross receiver array, higher reliability and longer ranges are expected using FSK, in addition to achieving compatibility between the two systems. This software includes a robust synchronization scheme, a spatial and an equalizing filter, a time-window self-adjusting process and the error control decoding.
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Date Issued: 2000
PURL: http://purl.flvc.org/fcla/dt/15788
Subject Headings: Underwater acoustics, Modems, Signal processing--Digital techniques
Format: Document (PDF)

Title: Multi-pulse excited linear prediction for synthesizing the guitar.
Creator: Leeds, David Scott., Florida Atlantic University, Erdol, Nurgun, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: In this paper we propose using parametric modeling by employing a Multi-Pulse Excited Linear Predictive Coded (MPE-LPC) filter to synthesize the guitar. First we introduce different methods for sound synthesis. A detailed discussion including the derivation of LPC and MPE presented. Then we study the impulse and steady state response of the guitar signal. An implementation of the MPE-LPC method to model the guitar is covered in detail and opportunities to improve the compression ratio are...
Show moreIn this paper we propose using parametric modeling by employing a Multi-Pulse Excited Linear Predictive Coded (MPE-LPC) filter to synthesize the guitar. First we introduce different methods for sound synthesis. A detailed discussion including the derivation of LPC and MPE presented. Then we study the impulse and steady state response of the guitar signal. An implementation of the MPE-LPC method to model the guitar is covered in detail and opportunities to improve the compression ratio are discussed. We then present simulation results with a set of fixed parameters, which are used as a benchmark to observe performance trade-offs by varying the model parameters to improve the compression ratio. Finally, we discuss limitations of the modeling algorithm for use with wide-band transient musical sounds and possible applications of the MPE-LPC model as a method to dynamically calculate samples for use with wavetable synthesis of steady state sounds.
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Date Issued: 2001
PURL: http://purl.flvc.org/fcla/dt/12759
Subject Headings: Computer music, Electric guitar, Signal processing--Digital techniques
Format: Document (PDF)

Title: Motion Compensation of an Ultra Short Baseline Array for the Acoustic Positioning of an Underwater Vehicle for Port Operations.
Creator: Bon, Antoine, Beaujean, Pierre-Philippe, Florida Atlantic University
Abstract/Description: A Motion Compensated (MC) Ultra Short Baseline (USBL) Acoustic Positioning System (APS) operable in shallow water and port environment has been implemented at Florida Atlantic University. Multi-tones signal modulation and log-likelihood maximization enable this APS to operate in volumes of water of less than 10 cubic meters. Standard deviations of the acoustic source elevation and azimuth estimates were computed to be 3 degrees in an 8 cubic meters test tank, and reduce to 0.9 degree in a 2...
Show moreA Motion Compensated (MC) Ultra Short Baseline (USBL) Acoustic Positioning System (APS) operable in shallow water and port environment has been implemented at Florida Atlantic University. Multi-tones signal modulation and log-likelihood maximization enable this APS to operate in volumes of water of less than 10 cubic meters. Standard deviations of the acoustic source elevation and azimuth estimates were computed to be 3 degrees in an 8 cubic meters test tank, and reduce to 0.9 degree in a 2 meters deep marina. The motion compensating system estimates the array position and orientation while merging noisy measurements from a Magnetic, Angular Rate, and Gravity (MARG) sensor and a Differential Global Positioning System (DGPS) using Kalman filters. Experiments show 0.67 and 2.67 degrees of error for the array tilt and heading estimates, and 0.74 meter for the array position estimate.
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Date Issued: 2007
PURL: http://purl.flvc.org/fau/fd/FA00012507
Subject Headings: Underwater navigation, Acoustical engineering, Adaptive signal processing, Underwater acoustic telemetry
Format: Document (PDF)

Title: Implementation and representation of the discrete wavelet transform.
Creator: Efthymoglou, George P., Florida Atlantic University, Erdol, Nurgun
Abstract/Description: This thesis presents a comprehensive analysis of a relatively new transform for discrete time signals, called the Discrete Wavelet Transform (DWT). We find how this transform is connected with the already existing theory of perfect reconstruction filter banks and the recently introduced theory of multiresolution analysis. We use the conditions obtained from these two theories in order to understand the construction of wavelet filters, which also generate continuous functions that prove to...
Show moreThis thesis presents a comprehensive analysis of a relatively new transform for discrete time signals, called the Discrete Wavelet Transform (DWT). We find how this transform is connected with the already existing theory of perfect reconstruction filter banks and the recently introduced theory of multiresolution analysis. We use the conditions obtained from these two theories in order to understand the construction of wavelet filters, which also generate continuous functions that prove to constitute an orthonormal basis for the L$\sp2$ space. We also investigate the connection of this transform to the sampled wavelet series of nonorthogonal functions with good time-frequency localization properties. Finally, we see the way that the DWT maps a discrete signal in the phase plane and the applications that such representations incorporate.
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Date Issued: 1993
PURL: http://purl.flvc.org/fcla/dt/14944
Subject Headings: Wavelets (Mathematics), Integrals, Singular, Signal processing--Digital techniques
Format: Document (PDF)

Title: Real time method for remote measurement of compressional wave attenuation.
Creator: DeBruin, Darryl L., Florida Atlantic University, Schock, Steven G.
Abstract/Description: An acoustic measurement system is developed to estimate the compressional wave attenuation of marine sediments in real time. A chirp sonar transmits filtered digital reflection data to a signal processing computer that processes the data on an AT&T DSP32C chip. The signal processing computer estimates and displays the center frequency of the processed pulse as it is attenuated by the ocean sediments. Wavelet modelling establishes the relationship between the center frequency shift and...
Show moreAn acoustic measurement system is developed to estimate the compressional wave attenuation of marine sediments in real time. A chirp sonar transmits filtered digital reflection data to a signal processing computer that processes the data on an AT&T DSP32C chip. The signal processing computer estimates and displays the center frequency of the processed pulse as it is attenuated by the ocean sediments. Wavelet modelling establishes the relationship between the center frequency shift and relaxation time, from which the sediment type and compressional wave attenuation are determined. Frequency contours from two different data sites demonstrate that the system is able to reliably estimate sediment type and compressional wave attenuation. Error introduced by noise is below 1% for noise levels less than 0.1 of the normalized processed signal. Random error in the estimates is minimized by determining reliable frequency values and by ensemble averaging the values.
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Date Issued: 1992
PURL: http://purl.flvc.org/fcla/dt/14824
Subject Headings: Marine sediments--Acoustic properties, Signal processing--Computer simulation
Format: Document (PDF)

Title: Non-separable two dimensional wavelets and their filter banks in polar coordinates.
Creator: Andric, Oleg., Florida Atlantic University, Erdol, Nurgun
Abstract/Description: The problems encountered in development and implementation of orthonormal two dimensional wavelet bases and their filter banks in polar coordinates are addressed. These wavelets and filter banks have possible applications in processing signals that are collected by sensors working in the polar coordinate system, such as biomedical and radar generated signals. The relationship between the space of measurable, square-integrable functions on the punctured polar coordinate system L^2(P) and space...
Show moreThe problems encountered in development and implementation of orthonormal two dimensional wavelet bases and their filter banks in polar coordinates are addressed. These wavelets and filter banks have possible applications in processing signals that are collected by sensors working in the polar coordinate system, such as biomedical and radar generated signals. The relationship between the space of measurable, square-integrable functions on the punctured polar coordinate system L^2(P) and space of measurable, square-integrable functions on the rectangular plane L^2(R^2) is developed. This allows us to develop complete wavelet bases in a more convenient and familiar surrounding of L^2(R^2) and to transport this theory to L^2(P). Corresponding filter banks are also developed. The implementation of wavelet analysis of punctured polar plane is discussed. An example of wavelet bases, filter banks, and implementation is provided.
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Date Issued: 1995
PURL: http://purl.flvc.org/fcla/dt/15190
Subject Headings: Wavelets (Mathematics), Coordinates, Polar, Signal processing--Mathematical models
Format: Document (PDF)

Title: Synchronous spatial array processing for underwater vehicle tracking.
Creator: Normand, Olivier., Florida Atlantic University, Schock, Steven G., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Navigation of Unmanned Underwater Vehicles (UUVs) is commonly assisted in confined areas by acoustic positioning systems. The Department of Ocean Engineenng at Florida Atlantic University is developing an altemative system based on submerged modems. This thesis describes an optimal target location estimation technique using a multi-channel spatial receiver array (Millscross) used as a development tool combined with a synchronous modem and transponder network mounted on buoys and UUVs. The...
Show moreNavigation of Unmanned Underwater Vehicles (UUVs) is commonly assisted in confined areas by acoustic positioning systems. The Department of Ocean Engineenng at Florida Atlantic University is developing an altemative system based on submerged modems. This thesis describes an optimal target location estimation technique using a multi-channel spatial receiver array (Millscross) used as a development tool combined with a synchronous modem and transponder network mounted on buoys and UUVs. The Millscross provides a reference to evaluate the performance of the navigation estimator. Spatial array principles are used to develop decoding and beamforming techniques to process modem messages, enabling the end user (the UUV) to estimate in real-time its own position and navigate in space. A simulation was used to compare actual results with theory and determine the processing and decoding algorithms. These algorithms were then applied to real data to estimate the target position (direction of arrival and geodetic coordinates).
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Date Issued: 2002
PURL: http://purl.flvc.org/fcla/dt/12917
Subject Headings: Underwater navigation, Underwater acoustics, Signal processing--Digital techniques
Format: Document (PDF)

Title: Studies on carrier-free (or ultra-wideband) radar performance under clutter and stealth-target environments.
Creator: Mendivil, Edwin David., Florida Atlantic University, De Groff, Dolores F., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: This thesis is concerned with the use of ultra-wideband radar detection specific to the following target and background considerations. (1) Statistical attributes of the RCS models of stealth-targets illuminated by ultra-wideband radars. (2) Analysis of radar echo signatures of low flying stealth-targets with a background of sea-clutter and illuminated by an ultra-wideband radar. (3) Analysis of impulse echoes from simple (planar) surface(s) coated with a radar absorbing material (RAM). The...
Show moreThis thesis is concerned with the use of ultra-wideband radar detection specific to the following target and background considerations. (1) Statistical attributes of the RCS models of stealth-targets illuminated by ultra-wideband radars. (2) Analysis of radar echo signatures of low flying stealth-targets with a background of sea-clutter and illuminated by an ultra-wideband radar. (3) Analysis of impulse echoes from simple (planar) surface(s) coated with a radar absorbing material (RAM). The first problem refers to the elucidation of Swerling-Marcum type classifications of RCS fluctuation(s) to characterize the stochastical aspects of the echoes from stealth-targets illuminated by an impulse from an ultra-wideband radar. In the second analysis, performance of a radar receiver configuration, using the log-likelihood function of the signal received from a stealth target flying at low altitude over the sea-surface is predicted. The third effort addressed provides analytical representations in time-domain of echoes from planar surface(s) coated with RAM's for normal incidence of ultra-wideband short pulse illumination.
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Date Issued: 1996
PURL: http://purl.flvc.org/fcla/dt/15278
Subject Headings: Radar, Signal processing, Radar cross sections, Stealth aircraft
Format: Document (PDF)

Title: Studies on the performance of reticles used in passive homing system.
Creator: Hoque, Md Monirul., Florida Atlantic University, Neelakanta, Perambur S.
Abstract/Description: Most infrared based target-seeking systems operate as passive detectors of the target with no energy being required to be transmitted from the seeker in order to detect a target. Reticles are used commonly in these passive homing seekers to modulate the incoming radiation from the target. Since signals are invariably corrupted by noise, the analysis of signal-to-noise characteristics of a passive homing system is crucial in elucidating its performance towards successful homing on the target....
Show moreMost infrared based target-seeking systems operate as passive detectors of the target with no energy being required to be transmitted from the seeker in order to detect a target. Reticles are used commonly in these passive homing seekers to modulate the incoming radiation from the target. Since signals are invariably corrupted by noise, the analysis of signal-to-noise characteristics of a passive homing system is crucial in elucidating its performance towards successful homing on the target. The objective of this thesis refers to the analysis of a passive homing system which employs a frequency modulated reticle. Studies pertinent to the feasibility aspect of using electrochromic, nonmoving reticles also constitute a part of the present study. In essence, the effort addressed in this work are concerned with the performance analysis and feasibilities considerations in using nonmoving reticles in passive homing systems in lieu of conventional rotating reticles.
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Date Issued: 1995
PURL: http://purl.flvc.org/fcla/dt/15138
Subject Headings: Reticles, Guided missiles--Guidance systems, Signal processing, Infrared radiation
Format: Document (PDF)

Title: Underwater acoustic channel estimation using multiple sources and receivers in shallow waters at very-high frequencies.
Creator: Kaddouri, Samar, Beaujean, Pierre-Philippe, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The underwater channel poses numerous challenges for acoustic communication. Acoustic waves suffer long propagation delay, multipath, fading, and potentially high spatial and temporal variability. In addition, there is no typical underwater acoustic channel; every body of water exhibits quantifiably different properties. Underwater acoustic modems are traditionally operated at low frequencies. However, the use of broadband, high frequency communication is a good alternative because of the...
Show moreThe underwater channel poses numerous challenges for acoustic communication. Acoustic waves suffer long propagation delay, multipath, fading, and potentially high spatial and temporal variability. In addition, there is no typical underwater acoustic channel; every body of water exhibits quantifiably different properties. Underwater acoustic modems are traditionally operated at low frequencies. However, the use of broadband, high frequency communication is a good alternative because of the lower background noise compared to low-frequencies, considerably larger bandwidth and better source transducer efficiency. One of the biggest problems in the underwater acoustic communications at high frequencies is time-selective fading, resulting in the Doppler spread. While many Doppler detection, estimation and compensation techniques can be found in literature, the applications are limited to systems operating at low frequencies contained within frequencies ranging from a few hundred Hertz to around 30 kHz.
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Date Issued: 2015
PURL: http://purl.flvc.org/fau/fd/FA00004384, http://purl.flvc.org/fau/fd/FA00004384
Subject Headings: Adaptive signal processing, MIMO systems, Signal processing -- Ditigal techniques -- Mathematics, Underwater acoustic telemetry, Underwater acoustics -- Evaluation, Wireless communication systems
Format: Document (PDF)

Title: Effect of message latency in an ATM network on signal processing.
Creator: Weber, Ralph Lawrence., Florida Atlantic University, Ilyas, Mohammad
Abstract/Description: Signal processing requires a steady flow of sampled data to be able to properly manipulate the signal to get the desired output. By using Asynchronous Transfer Mode (ATM) networks, it is possible to divide signal processing amongst a number of stations where each station can be specialized to a single function. Unfortunately, most commercially available ATM Network Interface Cards (NIC) only support message mode ATM Adaptation Layer 5 (AAL5) which is unsuitable to signal processing due to the...
Show moreSignal processing requires a steady flow of sampled data to be able to properly manipulate the signal to get the desired output. By using Asynchronous Transfer Mode (ATM) networks, it is possible to divide signal processing amongst a number of stations where each station can be specialized to a single function. Unfortunately, most commercially available ATM Network Interface Cards (NIC) only support message mode ATM Adaptation Layer 5 (AAL5) which is unsuitable to signal processing due to the delays of having to wait for an entire message to be formed prior to sending. It is shown that by using an ATM NIC using streaming mode AAL5, where cells are sent as soon as enough data to create an ATM cell of 48 bytes, leads to better quality signal processing. It is also shown that the message latency (time it takes for a message to traverse the network) is reduced by using streaming mode AAL5.
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Date Issued: 1997
PURL: http://purl.flvc.org/fcla/dt/15371
Subject Headings: Signal processing, Asynchronous transfer mode, Telecommunication--Message processing, Computer networks
Format: Document (PDF)

Title: Model-based classification of speech audio.
Creator: Thoman, Chris., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: This work explores the process of model-based classification of speech audio signals using low-level feature vectors. The process of extracting low-level features from audio signals is described along with a discussion of established techniques for training and testing mixture model-based classifiers and using these models in conjunction with feature selection algorithms to select optimal feature subsets. The results of a number of classification experiments using a publicly available speech...
Show moreThis work explores the process of model-based classification of speech audio signals using low-level feature vectors. The process of extracting low-level features from audio signals is described along with a discussion of established techniques for training and testing mixture model-based classifiers and using these models in conjunction with feature selection algorithms to select optimal feature subsets. The results of a number of classification experiments using a publicly available speech database, the Berlin Database of Emotional Speech, are presented. This includes experiments in optimizing feature extraction parameters and comparing different feature selection results from over 700 candidate feature vectors for the tasks of classifying speaker gender, identity, and emotion. In the experiments, final classification accuracies of 99.5%, 98.0% and 79% were achieved for the gender, identity and emotion tasks respectively.
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Date Issued: 2009
PURL: http://purl.flvc.org/FAU/210518
Subject Headings: Signal processing, Digital techniques, Speech processing systems, Sound, Recording and reproducing, Digital techniques, Pattern recognition systems
Format: Document (PDF)

Title: Combined spatial diversity and time equalization for broadband multiple channel underwater acoustic communications.
Creator: Skoro Kaskarovska, Violeta, Beaujean, Pierre-Philippe, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: High data rate acoustic communications become feasible with the use of communication systems that operate at high frequency. The high frequency acoustic transmission in shallow water endures severe distortion as a result of the extensive intersymbol interference and Doppler shift, caused by the time variable multipath nature of the channel. In this research a Single Input Multiple Output (SIMO) acoustic communication system is developed to improve the reliability of the high data rate...
Show moreHigh data rate acoustic communications become feasible with the use of communication systems that operate at high frequency. The high frequency acoustic transmission in shallow water endures severe distortion as a result of the extensive intersymbol interference and Doppler shift, caused by the time variable multipath nature of the channel. In this research a Single Input Multiple Output (SIMO) acoustic communication system is developed to improve the reliability of the high data rate communications at short range in the shallow water acoustic channel. The proposed SIMO communication system operates at very high frequency and combines spatial diversity and decision feedback equalizer in a multilevel adaptive configuration. The first configuration performs selective combining on the equalized signals from multiple receivers and generates quality feedback parameter for the next level of combining.
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Date Issued: 2015
PURL: http://purl.flvc.org/fau/fd/FA00004411, http://purl.flvc.org/fau/fd/FA00004411
Subject Headings: Adaptive signal processing, MIMO systems, Mobile geographic information systems, Signal processing -- Digital techniques, Underwater acoustic telemetry, Underwater acoustics -- Evaluation, Wireless communication systems
Format: Document (PDF)

Title: An Algorithm for the Automated Interpretation of Cardiac Auscultation.
Creator: Lieber, Claude, Erdol, Nurgun, Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: Cardiac auscultation, an important part of the physical examination, is difficult for many primary care providers. As a result, diagnoses are missed or auscultatory signs misinterpreted. A reliable, automated means of interpreting cardiac auscultation should be of benefit to both the primary care provider and to patients. This paper explores a novel approach to this problem and develops an algorithm that can be expanded to include all the necessary electronics and programming to develop such...
Show moreCardiac auscultation, an important part of the physical examination, is difficult for many primary care providers. As a result, diagnoses are missed or auscultatory signs misinterpreted. A reliable, automated means of interpreting cardiac auscultation should be of benefit to both the primary care provider and to patients. This paper explores a novel approach to this problem and develops an algorithm that can be expanded to include all the necessary electronics and programming to develop such a device. The algorithm is explained and its shortcomings exposed. The potential for further development is also expounded.
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Date Issued: 2016
PURL: http://purl.flvc.org/fau/fd/FA00004609, http://purl.flvc.org/fau/fd/FA00004609
Subject Headings: Phonocardiography., Signal processing., Pattern recognition systems., Imaging systems in medicine., Decision support systems., Medicine--Data processing.
Format: Document (PDF)

FAU Theses and Dissertations (78)	+ -
HBOI Faculty Contributions (2)	+ -
Honors Student Theses (1)	+ -

Signal processing (29)	+ -
Adaptive signal processing (20)	+ -
Signal processing--Digital techniques (18)	+ -
Digital techniques (12)	+ -
Underwater acoustic telemetry (10)	+ -

Underwater acoustics (9)	+ -
Wireless communication systems (7)	+ -
Wavelets (Mathematics) (6)	+ -
Speech processing systems (5)	+ -
Digital communications (4)	+ -
Underwater navigation (4)	+ -
Acoustical engineering (3)	+ -
Adaptive signal processing. (3)	+ -
Code division multiple access (3)	+ -
Design and construction (3)	+ -
Inertial navigation systems (3)	+ -
MIMO systems (3)	+ -
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