# IEEE Journal of Oceanic Engineering

## Filter Results

Displaying Results 1 - 25 of 31

Publication Year: 2010, Page(s):C1 - C4
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• ### IEEE Journal of Oceanic Engineering publication information

Publication Year: 2010, Page(s): C2
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• ### Excellence in Review 2009

Publication Year: 2010, Page(s):145 - 146
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• ### Editorial: Non-Rayleigh Reverberation and Clutter

Publication Year: 2010, Page(s):147 - 151
Cited by:  Papers (1)
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• ### Non-Rayleigh Echoes From Resolved Individuals and Patches of Resonant Fish at 2–4 kHz

Publication Year: 2010, Page(s):152 - 163
Cited by:  Papers (11)
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In this paper, the statistics of the echo envelope measured from fish is studied over a range of scattering geometries in the frequency band 2-4 kHz. In this frequency band, not only are these particular swimbladder-bearing fish resonant (at about 3.7 kHz) resulting in strong echoes, but also their target strength is narrowly distributed at these frequencies. In addition, their size distribution i... View full abstract»

• ### Dynamic Modeling of Discrete Biologics for Active Sonar Simulation

Publication Year: 2010, Page(s):164 - 174
Cited by:  Papers (2)
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In this paper, we propose a simple model for simulating the group dynamics of aggregate, discrete biologics in active undersea sonar. Using a Lagrangian representation, group behavior is modeled by a set of Newtonian forces and stochastic perturbations on a collection of point masses. Interactions comprise a grouping force, which gives a characteristic separation distance, and an arrayal force, wh... View full abstract»

• ### The Influence of Propagation Focusing on Clutter Statistics

Publication Year: 2010, Page(s):175 - 184
Cited by:  Papers (2)
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Fluctuations in reverberation (clutter) from scatterers at long range in shallow water can be affected by many mechanisms. Their statistics, in particular the scintillation index (SI), depend not only on the statistics of the scatterers (their physical distribution, shape, orientation, etc.) but on the outward and return propagation paths. This paper investigates the focusing effects due to forwar... View full abstract»

• ### Higher Moment Estimation for Shallow-Water Reverberation Prediction

Publication Year: 2010, Page(s):185 - 198
Cited by:  Papers (5)
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The modeling of the higher moments of shallow-water reverberation is addressed for problems where non-Rayleigh reverberation is caused by scattering from rough boundaries with chi-squared height distributions. Expressions for the first and third spatial moments of chi-squared height-distributed roughness are derived for exponential correlation functions corresponding to von-Karman second-order spe... View full abstract»

• ### Parabolic Equation Simulations of Reverberation Statistics From Non-Gaussian-Distributed Bottom Roughness

Publication Year: 2010, Page(s):199 - 208
Cited by:  Papers (10)
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In this paper, a two-way parabolic equation (PE) method is developed for modeling rough interface reverberation. The model is employed to estimate the reverberation envelope probability density function from bottom roughness with Gaussian and exponential height distributions. For Gaussian-distributed roughness, the PE gives envelope statistics that closely conform to the expected Rayleigh distribu... View full abstract»

• ### Fluctuations of Seafloor Backscatter Data From Multibeam Sonar Systems

Publication Year: 2010, Page(s):209 - 219
Cited by:  Papers (9)
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Several theoretical models of seafloor backscatter statistics developed over recent years show a reasonable agreement with experimental measurements made with sonar systems. However, methods of data collection and processing used in modern multibeam systems are often not taken into consideration when analyzing statistical characteristics of observed backscatter data. Fluctuations of various backsc... View full abstract»

• ### Statistics of Distinct Clutter Classes in Midfrequency Active Sonar

Publication Year: 2010, Page(s):220 - 229
Cited by:  Papers (14)
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The empirical distributions of normalized matched-filter echoes from a midfrequency active sonar with hyperbolic frequency-modulated waveforms in a myriad of oceanic environments are studied for three broad clutter (nontarget) classes: bottom structures, diffuse compact clutter, and compact nonstationary (moving) clutter. The distributions are characterized using the K -distribution (KD) and the g... View full abstract»

• ### Noise Estimation in Long-Range Matched-Filter Envelope Sonar Data

Publication Year: 2010, Page(s):230 - 235
Cited by:  Papers (6)
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In sonar signal processing when selecting a threshold for detection, it is necessary to consider the noise in the signal to achieve the desired rates of detection and false alarm. The clutter component of this noise, caused by scattering from environmental features, is often a limiting factor. This is particularly the case when active sonar systems operate in shallow water. Therefore, suitable mod... View full abstract»

• ### Non-Rayleigh Distributions in Underwater Acoustic Reverberation in a Patchy Environment

Publication Year: 2010, Page(s):236 - 241
Cited by:  Papers (9)
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In this communication, two main causes for the probability distribution function (pdf) of reverberation amplitude to deviate from the Rayleigh model are identified: (1) sonar configuration and (2) environmental variability. If the total environment may be considered as a patchwork of local environments that are resolvable by the sonar system, but not reliably distinguishable due to positional inac... View full abstract»

• ### Modeling the Effect of Seafloor Ripples on Synthetic Aperture Sonar Speckle Statistics

Publication Year: 2010, Page(s):242 - 249
Cited by:  Papers (10)
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The characterization and modeling of synthetic aperture sonar (SAS) image statistics is of importance for developing target-on-background detection and classification algorithms and for developing specialized filters for speckle noise reduction. In this paper, we present a model to predict the impact of amplitude scaling caused by seafloor ripples on SAS image speckle statistics. The continuous va... View full abstract»

• ### A Parametric Model for Characterizing Seabed Textures in Synthetic Aperture Sonar Images

Publication Year: 2010, Page(s):250 - 266
Cited by:  Papers (10)  |  Patents (1)
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High-resolution synthetic aperture sonar (SAS) systems yield finely detailed images of sea bottom environments. SAS image texture models must be capable of representing a wide variety of sea bottom environments including sand ripples, coral or rock formations, and flat hardpack. In this paper, a parameterized model for SAS image textures is derived from the autocorrelation functions (ACFs) of the ... View full abstract»

• ### Statistics of Echoes From a Directional Sonar Beam Insonifying Finite Numbers of Single Scatterers and Patches of Scatterers

Publication Year: 2010, Page(s):267 - 277
Cited by:  Papers (15)
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When a sonar beam sweeps across a field of scatterers and insonifies a different set of scatterers in each ping, the echoes can fluctuate significantly from ping to ping. For a homogeneous spatial distribution of scatterers in which there are a large number of scatterers in each sonar resolution cell, the echoes tend to be Rayleigh distributed. However, the echoes can be strongly nonRayleigh when ... View full abstract»

• ### Predicting Sonar False Alarm Rate Inflation Using Acoustic Modeling and a High-Resolution Terrain Model

Publication Year: 2010, Page(s):278 - 287
Cited by:  Papers (5)
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False alarm rates several orders of magnitude higher than the designed false alarm rate are frequently observed on active, low-frequency, towed array sonars. Increased false alarm rate originates from at least two effects: clutter and false alarm rate inflation (FARI). Clutter, or non-Rayleigh probability distributions of the matched-filter (MF) envelope, is often observed on high-resolution sonar... View full abstract»

• ### Reliable Methods for Estimating the $K$-Distribution Shape Parameter

Publication Year: 2010, Page(s):288 - 302
Cited by:  Papers (25)
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Parameter estimation for the K-distribution is an essential part of the statistical analysis of non-Rayleigh sonar reverberation or clutter for performance prediction, estimation of scattering properties, and for use in signal and information processing algorithms. Computational issues associated with maximum-likelihood (ML) estimation techniques for K-distribution parameters often force the use o... View full abstract»

• ### Toward the Development of Radar Scene Analyzer for Cognitive Radar

Publication Year: 2010, Page(s):303 - 313
Cited by:  Papers (13)
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In this paper, we propose a target signature search algorithm to address the radar scene analyzer in explicit terms for cognitive radar reception. A cognitive radar receiver encompasses two main blocks: the radar scene analyzer (RSA) and the Bayesian target tracker (BTT). The BTT needs to have prior knowledge of what it is looking for, such as terrain conditions, and the potential targets in that ... View full abstract»

• ### Tracking Small Targets in Heavy-Tailed Clutter Using Amplitude Information

Publication Year: 2010, Page(s):314 - 329
Cited by:  Papers (18)
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Harbor surveillance above and below the sea surface depends on sensors such as surveillance radar and multibeam sonar. These sensors attempt to detect and track moderately observable targets such as small boats or human divers in environments which often are characterized by heavy-tailed backgrounds. Target tracking in heavy-tailed environments is challenging even for moderate signal-to-noise rati... View full abstract»

• ### Methods for Identifying and Controlling Sonar Clutter

Publication Year: 2010, Page(s):330 - 354
Cited by:  Papers (10)
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Three methods for identifying, characterizing, and controlling active sonar clutter are described and demonstrated on broadband, low-frequency (<;1800 Hz) normalized data collected in two range-dependent, shallow-water environments: the Malta Plateau off Sicily and the Stanton Banks off Scotland. One method examines short time-scale clutter persistence to stabilize/minimize coherent propagation... View full abstract»

• ### Detection-Threshold Approximation for Non-Gaussian Backgrounds

Publication Year: 2010, Page(s):355 - 365
Cited by:  Papers (13)
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The detection-threshold (DT) term in the sonar equation describes the signal-to-noise ratio (SNR) required to achieve a specified probability of detection (Pd) for a given probability of false alarm (Pfa). Direct evaluation of DT requires obtaining the detector threshold (ft.) as a function of Pfa and then using h while inverting the often complicated relationship between SNR... View full abstract»

• ### Dynamic Load Positioning for Subsea Installation via Adaptive Neural Control

Publication Year: 2010, Page(s):366 - 375
Cited by:  Papers (15)
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In this paper, positioning control is investigated for the installation of subsea systems, with attached thrusters, under time-varying irrotational ocean current. Backstepping in combination with adaptive feedback approximation techniques is employed in the design of the control, with the option of high-gain observer for output feedback control. The stability of the design is demonstrated through ... View full abstract»

• ### Autopilot System Based on Color Recognition Algorithm and Internal Model Control Scheme for Controlling Approaching Maneuvers of a Small Boat

Publication Year: 2010, Page(s):376 - 387
Cited by:  Papers (6)
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This paper designs and develops an autopilot system for guiding the trajectory of a small boat as it performs an approaching maneuver within a harbor. In the proposed approach, two canvas targets are arranged in cascade on the berth to serve as leading marks to define the leading line along which to guide the boat toward the berthing standby region. The leading marks are captured by a charge-coupl... View full abstract»

• ### Bubble Size Measurements in Breaking Waves Using Optical Fiber Phase Detection Probes

Publication Year: 2010, Page(s):388 - 401
Cited by:  Papers (9)
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Knowledge of the two-phase flow generated by breaking waves is desirable if we are to fully understand their effect on environmental processes such as air-sea gas exchange and production of sea-salt aerosol. However, due to the difficulties in making measurements in the high void fraction bubble plumes generated immediately after breaking, little detailed information is available. This paper descr... View full abstract»

## Aims & Scope

The IEEE Journal of Oceanic Engineering (ISSN 0364-9059) is the online-only quarterly publication of the IEEE Oceanic Engineering Society (IEEE OES). The scope of the Journal is the field of interest of the IEEE OES, which encompasses all aspects of science, engineering, and technology that address research, development, and operations pertaining to all bodies of water. This includes the creation of new capabilities and technologies from concept design through prototypes, testing, and operational systems to sense, explore, understand, develop, use, and responsibly manage natural resources.

Full Aims & Scope

## Meet Our Editors

Editor-in-Chief
Mandar Chitre
Acoustic Research Laboratory
National University of Singapore