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Title: The effects of sensor mislocation in vertical arrays.
Creator: Joy, David Raymond., Florida Atlantic University, Glegg, Stewart A. L.
Abstract/Description: Knowledge of the effects of sensor mislocation is necessary for interpreting the outputs from vertical acoustic receiver arrays deployed in the ocean. The first phase of this study consists of deriving a numerical method to determine the geometric shape of a flexible array cable, anchored at its upper end and displaced by horizontal ocean currents. Analytic methods to verify the numerical method are then derived. The second phase of this study considers measurements of a simple sound source...
Show moreKnowledge of the effects of sensor mislocation is necessary for interpreting the outputs from vertical acoustic receiver arrays deployed in the ocean. The first phase of this study consists of deriving a numerical method to determine the geometric shape of a flexible array cable, anchored at its upper end and displaced by horizontal ocean currents. Analytic methods to verify the numerical method are then derived. The second phase of this study considers measurements of a simple sound source by perturbed array cables. The results are compared with those from straight cables to ascertain the effect of the sensor mislocation. These effects are evaluated in terms of array cable curvature and tilt.
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Date Issued: 1990
PURL: http://purl.flvc.org/fcla/dt/14595
Subject Headings: Underwater acoustics
Format: Document (PDF)

Title: MODEL EXPERIMENTS FOR 3-DIMENSIONAL PROPAGATION CHARACTERISTICS IN A WEDGE-SHAPED OCEAN.
Creator: Yoon, Jong Rak, Florida Atlantic University, Glegg, Stewart A. L., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The theoretical solution for acoustic propagation in a wedge-shaped ocean with ideal pressure-release boundaries predicts a well-defined beam which diverges as the energy propagates out towards deep water. Outside of the beam, shadow zones are formed, and the beam's spatial extent is determined by the lowest mode of propagation. The purpose of the experimental results presented here is to check the theoretical analyses, as part of an ongoing investigation into three dimensional propagation in...
Show moreThe theoretical solution for acoustic propagation in a wedge-shaped ocean with ideal pressure-release boundaries predicts a well-defined beam which diverges as the energy propagates out towards deep water. Outside of the beam, shadow zones are formed, and the beam's spatial extent is determined by the lowest mode of propagation. The purpose of the experimental results presented here is to check the theoretical analyses, as part of an ongoing investigation into three dimensional propagation in the ocean environment, and to investigate further the propagation characteristics of this type. It has been found that for downslope propagation, the spatial characteristics of the field in a direction parallel to the shore line are in good agreement with the theoretical solution and the azimuthal extent of the beam depends on the wedge angle and frequency.
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Date Issued: 1987
PURL: http://purl.flvc.org/fcla/dt/14387
Subject Headings: Underwater acoustics
Format: Document (PDF)

Title: Multipath compensation for underwater acoustic communication.
Creator: Bessios, Anthony G., Caimi, F. M., Harbor Branch Oceanographic Institute
Date Issued: 1994
PURL: http://purl.flvc.org/FCLA/DT/3183687
Subject Headings: Underwater acoustic telemetry, Underwater acoustics
Format: Document (PDF)

Title: HELIUM SPEECH PROCESSING BY LINEAR PREDICTION METHOD.
Creator: LEE, HYUN JICK., Florida Atlantic University, Erdol, Nurgun, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: The human speech production system is reviewed through general acoustic theory. Based upon that, the characteristics of helium speech is compared to normal speech. The Linear Prediction algorithm is derived for computer implementation by recursive formulas. The correction factors for the vocal tract area functions are found from simulated helium speech and normal speech data for four vowels. By the correction factors, new corrected area functions are applied to the Linear Prediction algorithm...
Show moreThe human speech production system is reviewed through general acoustic theory. Based upon that, the characteristics of helium speech is compared to normal speech. The Linear Prediction algorithm is derived for computer implementation by recursive formulas. The correction factors for the vocal tract area functions are found from simulated helium speech and normal speech data for four vowels. By the correction factors, new corrected area functions are applied to the Linear Prediction algorithm so that new synthesis filters can be built. The output of the algorithm is enhanced helium speech.
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Date Issued: 1985
PURL: http://purl.flvc.org/fcla/dt/14244
Subject Headings: Acoustical engineering, Underwater acoustics
Format: Document (PDF)

Title: A sparse volume array for imaging ocean ambient noise in the near-shore region.
Creator: Olivieri, Marc P., Florida Atlantic University, Glegg, Stewart A. L., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Ocean ambient noise has been studied extensively in the past, and several models have been developed to predict its level and to characterize it in different ocean environments. However, most of these studies have been motivated by the need to reduce the negative effect of the ambient noise on measurements. Recently, several studies have used the ambient noise to obtain information about the ocean floor and to achieve passive target detection. This dissertation describes the development of an...
Show moreOcean ambient noise has been studied extensively in the past, and several models have been developed to predict its level and to characterize it in different ocean environments. However, most of these studies have been motivated by the need to reduce the negative effect of the ambient noise on measurements. Recently, several studies have used the ambient noise to obtain information about the ocean floor and to achieve passive target detection. This dissertation describes the development of an Ambient Noise Sonar (ANS) which can be used to measure ambient noise directivity to obtain information about the environment. The system was designed for use on an Autonomous Underwater Vehicle (AUV) and has been used to study the ambient noise in the near shore region by investigating different types of noise in shallow water, such as boat traffic, biological noise and naturally occurring noise up to 20 kHz. There are two advantages to the ANS. First, when mounted on an AUV its mobility will allow the ambient noise to be mapped over an extended area. Second, the very small number of transducers (6 total) used in the array, makes this system suitable for AUV operations because it uses a limited amount of space and power. This dissertation presents the theory of the array processing and preliminary results including examples of boat noise, and biological noise. It was found that the noise from biological sources such as snapping shrimp contributed to the anisotropic component of the acoustic field. These biological sources were found to be concentrated around artificial structures such as piers and groins, and also around natural reefs. Finally noise maps of coastal areas are presented to illustrate the potential of this system to measure the noise field in the coastal region and to evaluate acoustic propagation using passive sources such as the biological noise clusters found along the coast. In the future the ANS will be integrated onto the AUV 'Ocean Explorer II'.
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Date Issued: 1997
PURL: http://purl.flvc.org/fcla/dt/12534
Subject Headings: Underwater acoustics, Acoustic imaging
Format: Document (PDF)

Title: The effect of sea surface motion on underwater communication systems.
Creator: Strutt, Guenael Thomas., Florida Atlantic University, LeBlanc, Lester R., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Underwater acoustic communications are significantly affected by time-varying multipath. Time-delays induced by multiple reactors on boundaries can be compensated for through equalization, and good transmission can be achieved. However, soundwaves reflected from moving scatterers on the sea surface undergo slight variations in frequency that significantly degrade the performance of communication devices. Ocean data was collected to evaluate the amount of Doppler-spread induced by wind-driven...
Show moreUnderwater acoustic communications are significantly affected by time-varying multipath. Time-delays induced by multiple reactors on boundaries can be compensated for through equalization, and good transmission can be achieved. However, soundwaves reflected from moving scatterers on the sea surface undergo slight variations in frequency that significantly degrade the performance of communication devices. Ocean data was collected to evaluate the amount of Doppler-spread induced by wind-driven surface waves. A model for the shallow water acoustic channel is discussed and implemented using a simplified approach to the gaussian-beam ray-tracing algorithm. This leads to the definition of the spreading function, a convenient tool to describe fading channels. The spreading function serves as a reference for the simulation of a classic digital communication setup, using baseband antipodal equalization. It is shown how frequency-spreading, a consequence of sea surface motion, affects the resulting error rate.
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Date Issued: 1999
PURL: http://purl.flvc.org/fcla/dt/15675
Subject Headings: Underwater acoustics, Acoustic surface waves
Format: Document (PDF)

Title: Characterization of the acoustic signature of an Ocean Explorer class AUV.
Creator: Lambe, Frederic Lionel., Florida Atlantic University, Cuschieri, Joseph M., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: The radiated noise from Autonomous Underwater Vehicles (AUV's) can interfere with on-board sensors and with certain type of missions. It is thus important to understand the parameters controlling the AUV self noise. In this thesis, measurement techniques and analyses are developed to investigate the mechanisms contributing to the acoustic noise of an Ocean Explorer class AUV. Measurements of the AUV acoustic signature are performed in a reverberant tank, after the tank is qualified to...
Show moreThe radiated noise from Autonomous Underwater Vehicles (AUV's) can interfere with on-board sensors and with certain type of missions. It is thus important to understand the parameters controlling the AUV self noise. In this thesis, measurement techniques and analyses are developed to investigate the mechanisms contributing to the acoustic noise of an Ocean Explorer class AUV. Measurements of the AUV acoustic signature are performed in a reverberant tank, after the tank is qualified to establish a reliable procedure to measure the AUV source levels. The measurement results are compared that obtained in an anechoic tank and in open-water. Acoustic measurements are correlated with vibration measurements performed on various components of the AUV, in order to identify the dominant components. From the results, some preliminary mitigation procedures to reduce the AUV acoustic signature are developed.
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Date Issued: 1999
PURL: http://purl.flvc.org/fcla/dt/15618
Subject Headings: Oceanographic submersibles, Underwater acoustics
Format: Document (PDF)

Title: Design and development of a high-speed underwater acoustic modem.
Creator: Alleyne, Jochen Raoul, Florida Atlantic University, LeBlanc, Lester R.
Abstract/Description: The design, development and performance of an acoustic modem using spread spectrum modulation techniques in order to reduce multipath interference is detailed in this thesis. The design also includes a method to correct for Doppler shifts in the received data. Finally, error detection and correction are utilized in order to improve the robustness of the transmitted data. The results of field experiments with the modem are used to analyze the performance of the modem under a variety of...
Show moreThe design, development and performance of an acoustic modem using spread spectrum modulation techniques in order to reduce multipath interference is detailed in this thesis. The design also includes a method to correct for Doppler shifts in the received data. Finally, error detection and correction are utilized in order to improve the robustness of the transmitted data. The results of field experiments with the modem are used to analyze the performance of the modem under a variety of conditions. These results are then used as a basis from which to draw conclusions about the spread spectrum technique.
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Date Issued: 1997
PURL: http://purl.flvc.org/fcla/dt/15520
Subject Headings: Modems, Underwater acoustics
Format: Document (PDF)

Title: Experimental analysis of the AUV acoustic signature.
Creator: Frandsen, Susan Eileen., Florida Atlantic University, Cuschieri, Joseph M.
Abstract/Description: This thesis presents an experimental analysis of the acoustic signature of an Ocean Explorer class AUV. The experimental analysis consists of three parts. The first part reports the measurements performed in an open water environment at NSWC in Lake Pend Oreille, Idaho. The second part reports on measurements performed at the FAU test tank on a mock model of the AUV and the third part reports the measurements also in the FAU test tank of the AUV under typical operating conditions. The model...
Show moreThis thesis presents an experimental analysis of the acoustic signature of an Ocean Explorer class AUV. The experimental analysis consists of three parts. The first part reports the measurements performed in an open water environment at NSWC in Lake Pend Oreille, Idaho. The second part reports on measurements performed at the FAU test tank on a mock model of the AUV and the third part reports the measurements also in the FAU test tank of the AUV under typical operating conditions. The model measurement results were also used to verify the prediction capabilities of a numerical FE model of the AUV using the reciprocity method. The measurements in the FAU tank considered different operating conditions and different mounting of the podule inside the AUV. The podule contains the main mechanical components of the AUV, which are the propulsion motor and the control surface motors. Also considered in these measurements is the influence of the propeller and the influence of covering the aft section of the AUV with a compliant layer. The results of this analysis show that the type of mounting of the podule is not very significant and that significant energy is transferred through the water trapped in between the podule and the hull. Furthermore, the propeller has a significant influence on the acoustic signature since it generates distinct tones. These tones were also observed in the results of the open water measurements.
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Date Issued: 2001
PURL: http://purl.flvc.org/fcla/dt/12768
Subject Headings: Underwater acoustics, Oceanographic submersibles
Format: Document (PDF)

Title: A wavelet-based detector for underwater communication.
Creator: Petljanski, Branko., Florida Atlantic University, Erdol, Nurgun, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: The need for reliable underwater communication at Florida Atlantic University is critical in transmitting data to and from Autonomous Underwater Vehicles (AUV) and remote sensors. Since a received signal is corrupted with ambient ocean noise, the nature of such noise is investigated. Furthermore, we establish connection between ambient ocean noise and fractal noise. Since the matched filter is designed under the assumption that noise is white, performance degradation of the matched filter due...
Show moreThe need for reliable underwater communication at Florida Atlantic University is critical in transmitting data to and from Autonomous Underwater Vehicles (AUV) and remote sensors. Since a received signal is corrupted with ambient ocean noise, the nature of such noise is investigated. Furthermore, we establish connection between ambient ocean noise and fractal noise. Since the matched filter is designed under the assumption that noise is white, performance degradation of the matched filter due non-white noise is investigated. We show empirical results that the wavelet transform provides an approximate Karhunen-Loeve expansion for 1/f-type noise. Since whitening can improve only broadband signals, a new method for synchronization signal design in wavelet subspaces with increased energy-to-peak amplitude ratio is presented. The wavelet detector with whitening of fractal noise and detection in wavelet subspace is shown. Results show that the wavelet detector improves detectability, however this is below expectation due to differences between fractal noise and ambient ocean noise.
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Date Issued: 2001
PURL: http://purl.flvc.org/fcla/dt/12778
Subject Headings: Wavelets (Mathematics), Underwater acoustics
Format: Document (PDF)

Title: Digital acoustic communications using decision directed learning.
Creator: Alleyne, Jochen Raoul, Florida Atlantic University, LeBlanc, Lester R., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: This document serves as a dissertation for the Doctor of Philosophy in Ocean Engineering degree at Florida Atlantic University's Department of Ocean Engineering. This dissertation documents the design, development, and performance analysis of an acoustic receiver system that incorporates a decision directed learning filter for acoustic multi-phase shift keying signals. The system makes use of advanced signal processing, inclusive of spatial diversity and decision directed learning techniques...
Show moreThis document serves as a dissertation for the Doctor of Philosophy in Ocean Engineering degree at Florida Atlantic University's Department of Ocean Engineering. This dissertation documents the design, development, and performance analysis of an acoustic receiver system that incorporates a decision directed learning filter for acoustic multi-phase shift keying signals. The system makes use of advanced signal processing, inclusive of spatial diversity and decision directed learning techniques in order to decode digital acoustic data. Error correcting techniques are also employed as well as methods of analyzing the efficiency of the system.
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Date Issued: 2001
PURL: http://purl.flvc.org/fcla/dt/11951
Subject Headings: Underwater acoustic telemetry, Digital communications, Acoustic filters
Format: Document (PDF)

Title: Model experiments for the acoustic field in a water column which includes the effects of shear in marine sediments.
Creator: Hundley, Allen John., Florida Atlantic University, Glegg, Stewart A. L.
Abstract/Description: A scaled, horizontally stratified shallow water marine acoustic model is constructed for the purpose of investigating the sound field resulting from long range propagation. The characteristics of this sound field in the water column are strongly dependent upon properties of the surficial sediment. One effect is the conversion from compressional waves in the water column to shear waves in the sediment at grazing angles less than the critical. To model a shallow marine environment, concrete is...
Show moreA scaled, horizontally stratified shallow water marine acoustic model is constructed for the purpose of investigating the sound field resulting from long range propagation. The characteristics of this sound field in the water column are strongly dependent upon properties of the surficial sediment. One effect is the conversion from compressional waves in the water column to shear waves in the sediment at grazing angles less than the critical. To model a shallow marine environment, concrete is used as a substrate rock and laminating epoxy is used to model a surficial sediment. Preliminary tests of the effects of the model's environment are performed, and the range dependent sound field as a function of depth is measured for several CW frequencies. These sound field profiles are compared with an approximate predictive theory, and with a numerical solution which treats the sediment properties exactly.
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Date Issued: 1990
PURL: http://purl.flvc.org/fcla/dt/14618
Subject Headings: Underwater acoustics, Marine sediments--Acoustic properties
Format: Document (PDF)

Title: Modelling of underwater ambient noise due to whitecaps.
Creator: Elisseeff, Pierre., Florida Atlantic University, Glegg, Stewart A. L.
Abstract/Description: A theoretical model accounting for underwater ambient noise due to whitecap-generated bubbles and drop-impacts is developed to investigate the possible mechanisms of ocean noise generation. A general analysis is laid down, leading to expressions of the noise spectrum in an undefined environment. Subsequently the cases of isovelocity and stratified deep oceans are considered, and specific expressions are derived. The stratified deep ocean estimations of the directional spectrum are then...
Show moreA theoretical model accounting for underwater ambient noise due to whitecap-generated bubbles and drop-impacts is developed to investigate the possible mechanisms of ocean noise generation. A general analysis is laid down, leading to expressions of the noise spectrum in an undefined environment. Subsequently the cases of isovelocity and stratified deep oceans are considered, and specific expressions are derived. The stratified deep ocean estimations of the directional spectrum are then compared to experimental data and a good agreement is found. Finally the absolute noise levels due to bubbles and drop impacts are discussed, and bubble noise is found to be larger than drop impact noise. The collective bubble oscillation hypothesis is also discussed, and although clues are given for and against this hypothesis no rigorous justification for this has been found.
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Date Issued: 1992
PURL: http://purl.flvc.org/fcla/dt/14784
Subject Headings: Underwater acoustics--Measurement, Acoustic surface waves
Format: Document (PDF)

Title: Modeling the acoustic signature of an Ocean Explorer class autonomous underwater vehicle.
Creator: Debiesme, Francois-Xavier., Florida Atlantic University, Cuschieri, Joseph M.
Abstract/Description: Autonomous Underwater Vehicles (AUV) rely on acoustics for a number of mission functions such as communications (Acoustic Modem) and vision (Forward and Side Looking Sonars). The AUV acoustic signature (self-noise and vibration) can thus interfere with AUV operations. Additionally, underwater measurements such as turbulence measurements can be contaminated by interference between the AUV generated acoustics pressures and the low pressures of the turbulence. In this thesis a Finite Element and...
Show moreAutonomous Underwater Vehicles (AUV) rely on acoustics for a number of mission functions such as communications (Acoustic Modem) and vision (Forward and Side Looking Sonars). The AUV acoustic signature (self-noise and vibration) can thus interfere with AUV operations. Additionally, underwater measurements such as turbulence measurements can be contaminated by interference between the AUV generated acoustics pressures and the low pressures of the turbulence. In this thesis a Finite Element and Boundary Element approach is developed to characterize the self-noise (vibration and radiated sound pressure) of a simplified FAU Ocean Explorer AUV. Mechanical excitation from the "podule", which contains the motors for the propulsion and motion control, is assumed in the analysis. The low frequency (less than 1Khz) results are dominated by two types of modes. One type associated with the motion of the "podule" as a rigid body on the vibration isolation supports that connects it to the rest of the AUV structure. The second type is associated with local structural deformations of the "podule", support frame, and AUV hull. Modifying the stiffness of the supports reduces the frequency of the rigid body modes of the "podule", but does not influence the frequencies of the local structural deformations of the "podule" and the rest of the AUV. Decreasing the stiffness of the supports should result in a reduced AUV acoustic signature.
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Date Issued: 2000
PURL: http://purl.flvc.org/fcla/dt/15764
Subject Headings: Oceanographic submersibles, Underwater acoustics, Acoustic models
Format: Document (PDF)

Title: Impact of noise on seafloor property estimation using Biot model parameters obtained through an inversion of chirp sonar data.
Creator: Munro, Lachlan I., Florida Atlantic University, Schock, Steven G., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: This thesis describes the development and testing of an inversion method, based on the Biot-Stoll acoustic wave propagation model, for estimating sediments properties from acoustic reflection measurements of the seabed. The Biot-Stoll model is a physics-based model which describes the propagation of compressional and shear waves through porous media. Given the physical sediment properties of the seabed, the pressure reflection coefficient of the seabed is calculated using the Biot-Stoll model...
Show moreThis thesis describes the development and testing of an inversion method, based on the Biot-Stoll acoustic wave propagation model, for estimating sediments properties from acoustic reflection measurements of the seabed. The Biot-Stoll model is a physics-based model which describes the propagation of compressional and shear waves through porous media. Given the physical sediment properties of the seabed, the pressure reflection coefficient of the seabed is calculated using the Biot-Stoll model. The proposed inversion procedure varies sediment properties until a least squares fit is obtained between the output of the model and the measured reflection coefficient. Random errors are introduced into the reflection coefficient measurement to determine the effect of measurement error in the estimation of seabed properties such as permeability, porosity, mean grain diameter, and sediment type.
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Date Issued: 2003
PURL: http://purl.flvc.org/fcla/dt/13084
Subject Headings: Underwater acoustics, Marine sediments--Acoustic properties
Format: Document (PDF)

Title: Radius distribution of ocean near surface bubbles.
Creator: Auffret, Yvan., Florida Atlantic University, Glegg, Stewart A. L.
Abstract/Description: This study proposed to determine an ocean surface bubble radius distribution using theoretical noise models, experimental noise spectral data and a theoretical model for the bubble size distribution. The obtained distribution was compared to previous experimental distributions. A good agreement was found for the radius upper cut-off but the shape and the peak radius of the distribution are different from experimental observations. The most probable reasons for these differences were given....
Show moreThis study proposed to determine an ocean surface bubble radius distribution using theoretical noise models, experimental noise spectral data and a theoretical model for the bubble size distribution. The obtained distribution was compared to previous experimental distributions. A good agreement was found for the radius upper cut-off but the shape and the peak radius of the distribution are different from experimental observations. The most probable reasons for these differences were given. Moreover, the validity of recent theoretical bubble noise models was checked. Eventually, the main limitations of the study were pointed out and directions for future works were given.
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Date Issued: 1993
PURL: http://purl.flvc.org/fcla/dt/14922
Subject Headings: Underwater acoustics, Acoustic surface waves, Bubbles
Format: Document (PDF)

Title: Validation of numerical modelling for long range acoustic propagation.
Creator: Riley, Joseph M., Florida Atlantic University, Glegg, Stewart A. L., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Laboratory scale measurements were conducted to validate numerical prediction models used to predict the acoustic field in a shallow water ocean environment. Experimental measurements were conducted in a range independent environment which included the effects of shear in marine sediments and in a depth varying range dependent environment. Good agreement between the experimental measurements and the numerical prediction codes were obtained using optimized values for the input parameters of...
Show moreLaboratory scale measurements were conducted to validate numerical prediction models used to predict the acoustic field in a shallow water ocean environment. Experimental measurements were conducted in a range independent environment which included the effects of shear in marine sediments and in a depth varying range dependent environment. Good agreement between the experimental measurements and the numerical prediction codes were obtained using optimized values for the input parameters of the environmental model. In comparing experimental measurements to the numerical prediction codes it became apparent that the codes were very sensitive to the input parameters describing the bottom boundary of the ocean waveguide.
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Date Issued: 1992
PURL: http://purl.flvc.org/fcla/dt/14819
Subject Headings: Acoustical engineering, Underwater acoustics, Marine sediments
Format: Document (PDF)

Title: A broadband signal processor for acoustic imaging using ambient noise.
Creator: Olivieri, Marc P., Florida Atlantic University, Glegg, Stewart A. L., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Buckingham et al. (Nature Vol. 356, p 327) first introduced the concept of acoustic imaging using ambient noise as a method for passively detecting objects in the ocean. Several analytical studies followed, and it was shown that a two dimensional acoustic image could be obtained based on this approach, and that at least 900 pixels are necessary to restitute the details of spherical objects placed in an underwater sound channel. The alternative approach described in this paper is based on a...
Show moreBuckingham et al. (Nature Vol. 356, p 327) first introduced the concept of acoustic imaging using ambient noise as a method for passively detecting objects in the ocean. Several analytical studies followed, and it was shown that a two dimensional acoustic image could be obtained based on this approach, and that at least 900 pixels are necessary to restitute the details of spherical objects placed in an underwater sound channel. The alternative approach described in this paper is based on a signal processing which uses the broadband nature of the ambient noise in the ocean, and therefore, optimizes the use of available sound energy scattered by the object. Images with thousands of pixels can be obtained using a relatively small number of transducers. This method has been validated using simple experiments in air, scaled to represent an ocean application, and results showing images of various objects will be presented.
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Date Issued: 1994
PURL: http://purl.flvc.org/fcla/dt/15065
Subject Headings: Acoustic imaging, Signal processing, Underwater acoustics
Format: Document (PDF)

Title: Compound compensation strategies for wireless data communications over the multimodal acoustic ocean waveguide.
Creator: Bessios, Anthony G., Harbor Branch Oceanographic Institute
Date Issued: 1996
PURL: http://purl.flvc.org/FCLA/DT/3351960
Subject Headings: Underwater acoustic telemetry, Underwater acoustics, Wireless communication systems, Wave guides
Format: Document (PDF)

Title: High-rate wireless data communications: an underwater acoustic communications framework at the physical layer.
Creator: Bessios, Anthony G., Caimi, F. M., Harbor Branch Oceanographic Institute
Date Issued: 1996
PURL: http://purl.flvc.org/FCLA/DT/3351962
Subject Headings: Wireless communication systems, Underwater acoustic telemetry, Underwater acoustics, Digital communications
Format: Document (PDF)

FAU Theses and Dissertations (78)	+ -
HBOI Faculty Contributions (7)	+ -
FAU Undergraduate Student Research (1)	+ -

Underwater acoustics (52)	+ -
Underwater acoustic telemetry (17)	+ -
Underwater acoustics--Measurement (11)	+ -
Adaptive signal processing (9)	+ -
Acoustical engineering (8)	+ -

Acoustic surface waves (7)	+ -
Marine sediments--Acoustic properties (6)	+ -
Oceanographic submersibles (5)	+ -
Signal processing--Digital techniques (5)	+ -
Wireless communication systems (5)	+ -
Digital communications (4)	+ -
Signal processing (4)	+ -
Digital techniques (3)	+ -
Fluid dynamics (3)	+ -
MIMO systems (3)	+ -
Mathematical models (3)	+ -
Remote submersibles (3)	+ -
Seawater--Acoustic properties (3)	+ -
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Measurement (2)	+ -
Modems (2)	+ -
Noise--Measurement (2)	+ -
Numerical solutions (2)	+ -

Florida (1)	+ -
St. Lucie River Estuary (1)	+ -
St. Lucie River Estuary (Fla.) (1)	+ -

Electronic Thesis or Dissertation (78)	+ -
article (7)	+ -
abstract (1)	+ -

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