Download or read book Passive Acoustic Localization and Tracking Using Arrays and Directional Sensors written by Ludovic Tenorio-Hallé and published by . This book was released on 2021 with total page 129 pages. Available in PDF, EPUB and Kindle. Book excerpt: In bioacoustics, passive acoustic localization and tracking plays an important role in studying marine mammals and other organisms that produce underwater sounds. However, the implementation of such techniques faces many practical challenges, such as lack of environmental data for accurately modeling acoustic propagation, uncertainties in sensor position, time-synchronization of autonomous instruments, and logistical constraints due to large arrays. The three research chapters of this dissertation cumulatively address these hurdles. Chapter 2 develops a reformulation of the "double-difference" method for long-range tracking of acoustic sources. Originally developed for high-resolution localization of earthquakes across a network of widely distributed sensor, the double-difference approach is here adapted to exploit acoustic multipath on a vertical array, deployed in a deep-water waveguide. Results are shown to provide high-precision relative depth and range tracks of sources on the order of 50 km away, by compensating for biases caused by underdetermined array tilt and sound speed model. The method is demonstrated on both a towed acoustic source and a sperm whale (Physeter macrocephalus). Chapter 3 presents a passive time-synchronization technique for independent autonomous acoustic recorders. This approach relies on the coherent ambient noise sources maintaining the same statistical angular distribution around the instruments. Under this assumption, the temporal evolution of the cross-correlation function between sensor pairs reveals their relative time drift. This method enables continuous measurements of clock offset, including small-scale non-linear fluctuations of the drift, otherwise unobservable with standard time-synchronization techniques. Data from a field study in San Ignacio Lagoon, Mexico, is used to demonstrate this technique which is here applied to low frequency pulses, most likely originating from croaker fish (Sciaenidae family). Chapter 4 uses acoustic vector sensor data to track multiple sources simultaneously. The method is demonstrated on singing humpback whales (Megaptera novaeangliae) off western Maui. Here, the directional capabilities of vector sensors are exploited to identify and match azimuthal tracks from multiple sources between sensors, yielding localized whale tracks in terms of latitude and longitude over time. This approach shows potential for further applications such as tracking boats and analyzing the directional properties of ambient noise field.

Download or read book Passive Localization of an Underwater Acoustic Source Using Directional Sensors written by and published by . This book was released on 1995 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advances in Passive Acoustic Detection Localization and Tracking Applied to Unmanned Underwater Vehicles written by Kristen Railey Kita and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Detection, classification, localization, and tracking (DCLT) of unmanned underwater vehicles (UUVs) in the presence of shipping traffic is a critical task for passive acoustic harbor security systems. In general, vessels can be tracked by their unique acoustic signature due to machinery vibration and cavitation noise. However, cavitation noise of UUVs is considerably quieter than ships and boats, making detection significantly more challenging. In this thesis, I demonstrated that it is possible to passively track a UUV from its highfrequency motor noise using a stationary array in shallow-water experiments with passing boats. First, causes of high frequency tones were determined through direct measurements of two UUVs at a range of speeds. From this analysis, common and dominant features of noise were established: strong tones at the motor’s pulse-width modulated frequency and its harmonics. From the unique acoustic signature of the motor, I derived a high-precision, remote sensing method for estimating propeller rotation rate. In shallow-water UUV field experiments, I demonstrated that detecting a UUV from motor noise, in comparison to broadband noise from the vehicle, reduces false alarms from 45% to 8.4% for 90% true detections. Beamforming on the motor noise, in comparison to broadband noise, improved the bearing accuracy by a factor of 3.2×. Because the signal is also high-frequency, the Doppler effect on motor noise is observable and I demonstrate that range rate can be measured. Furthermore, measuring motor noise was a superior method to the “detection of envelope modulation on noise” algorithm for estimating the propeller rotation rate. Extrapolating multiple measurements from the motor signature is significant because Bearing-Doppler-RPM measurements outperform traditional bearing-Doppler target motion analysis. In the unscented Kalman filter implementation, the tracking solution accuracy for bearing, bearing rate, range, and range rate improved by a factor 2.2×, 15.8×, 3.1×, and 6.2× respectively. These findings are significant for improving UUV localization and tracking, and for informing the next-generation of quiet UUV propulsion systems.

Download or read book Audio Source Separation and Speech Enhancement written by Emmanuel Vincent and published by John Wiley & Sons. This book was released on 2018-10-22 with total page 517 pages. Available in PDF, EPUB and Kindle. Book excerpt: Learn the technology behind hearing aids, Siri, and Echo Audio source separation and speech enhancement aim to extract one or more source signals of interest from an audio recording involving several sound sources. These technologies are among the most studied in audio signal processing today and bear a critical role in the success of hearing aids, hands-free phones, voice command and other noise-robust audio analysis systems, and music post-production software. Research on this topic has followed three convergent paths, starting with sensor array processing, computational auditory scene analysis, and machine learning based approaches such as independent component analysis, respectively. This book is the first one to provide a comprehensive overview by presenting the common foundations and the differences between these techniques in a unified setting. Key features: Consolidated perspective on audio source separation and speech enhancement. Both historical perspective and latest advances in the field, e.g. deep neural networks. Diverse disciplines: array processing, machine learning, and statistical signal processing. Covers the most important techniques for both single-channel and multichannel processing. This book provides both introductory and advanced material suitable for people with basic knowledge of signal processing and machine learning. Thanks to its comprehensiveness, it will help students select a promising research track, researchers leverage the acquired cross-domain knowledge to design improved techniques, and engineers and developers choose the right technology for their target application scenario. It will also be useful for practitioners from other fields (e.g., acoustics, multimedia, phonetics, and musicology) willing to exploit audio source separation or speech enhancement as pre-processing tools for their own needs.

Download or read book Transformational Science And Technology For The Current And Future Force With Cd rom Proceedings Of The 24th Us Army Science Conference written by A M Rajendran and published by World Scientific. This book was released on 2006-11-08 with total page 601 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides the reader with a unique opportunity to understand the basic and applied research and technology areas that support applications to enable Transformational capabilities for US Soldiers. The research papers are in line with the theme of the 24th Army Science Conference: “Transformational Science and Technology for the Current and Future Force,” emphasizing the critical role of Science and Technology in addressing the significant challenges posed by Global War On Terrorism while simultaneously developing Transformational capabilities for the Future Force.

Download or read book Optimal Source Localization and Tracking Using Arrays with Uncertainties in Sensor Locations written by Mordechai Segal and published by . This book was released on 1989 with total page 590 pages. Available in PDF, EPUB and Kindle. Book excerpt: We develop a computationally efficient iterative algorithm for source localization and tracking using active/passive arrays with uncertainties in sensor locations. We suppose that the available data consist of time delay, or differential time delay, measurements of the signal wavefront across the array. We consider a general senario in which the array uncertainties may be correlated in time and in space. The proposed algorithm is optimal in the sense that it converges montonically to the Maximum Likelihood (ML) estimate of the source trajectory parameters. In the case of multiple sources, the algorithm makes an essential use of the information available from all sources to reduce the array uncertainties (the so-called array callibration) and thus to improve the localization accuracy of each signal source. We also derive new expressions for the log-likelihood gradient, the Hessian, and the Fisher's information matrix, that may be used for efficient implementation of gradient based algorithms, and for assessing the mean square error of the resulting ML parameter estimates.

Download or read book Sound Source Localization written by Richard R. Fay and published by Springer Science & Business Media. This book was released on 2006-05-20 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Springer Handbook of Auditory Research presents a series of compreh- sive and synthetic reviews of the fundamental topics in modern auditory - search. The volumes are aimed at all individuals with interests in hearing research including advanced graduate students, postdoctoral researchers, and clinical investigators. The volumes are intended to introduce new investigators to important aspects of hearing science and to help established investigators to better understand the fundamental theories and data in ?elds of hearing that they may not normally follow closely. Each volume presents a particular topic comprehensively, and each serves as a synthetic overview and guide to the literature. As such, the chapters present neither exhaustive data reviews nor original research that has not yet appeared in peer-reviewed journals. The volumes focus on topics that have developed a solid data and conceptual foundation rather than on those for which a literature is only beginning to develop. New research areas will be covered on a timely basis in the series as they begin to mature.

Download or read book Directional Hearing at the Micro scale written by Andrew Reid and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Miniaturization of sound localization sensors arrays is heavily constrained by the limited directional cues in intensity difference and phase difference available at the microscale. Micro-Electro Mechanical System (MEMS) sound localization sensors inspired by the auditory system of Ormia ochracea offer a potential solution to this problem by the apparent amplification of the available intensity and phase difference between the measurement points. An inherent limitation of these systems is that significant amplification of these cues is only available on or near one of the resonant frequencies of the device, severely limiting it [sic] application as a directional microphone. A lower amplification of directional cues can be achieved across a wide frequency range, forcing designers to compromise the goal of high amplification of directional cues to operate across the audio range. Here we present an alternative approach, namely a system optimized for the maximum amplification of directional cues across a narrow bandwidth operating purely as a sound localization sensor for wide-band noise. In the devices presented in chapter four we present sound-localization sensors where the directional sensitivity is enhanced by increasing the coupling strength beyond the 'dual optimization' point, which represents the collocation of a local maximum in directional sensitivity and a local minimum in non-linearity, compensating for the loss of the desirable linearity of the system by restricting the angular range of operation. Intensity gain achieved is 16.3 dB at 10° sound source azimuth with a linear directional sensitivity of 1.6 dB per degree, while linear directional sensitivity in phase difference gain shows a seven fold increase over the 'dual optimization' point of 8 degrees per degree. In addition, during the course of this work it was discovered that the methods used to calculate the amplified intensity difference between the measurement points introduce unwelcome Cauchy noise which is difficult to reduce. Later iterations of the device demonstrate the process of optimization of a sound localization sensor for the maximum amplification of directional cues across a narrow bandwidth can be used to overcome that error, as well as describing mathematically what appears to have been a commonly encountered but unpublished problem with Ormia inspired directional sensors. In the second part of the thesis, beginning in Chapter 5 the sound localization strategies of another acoustic insect, the lesser wax moth Achroia grisella, is examined. Moths differ somewhat because their ears generally function as simple bat detectors with relatively little directional ability. Those moths that use sound signals for mating communication represent a yet more special case, as these species can localize sound sources but singing and the ability to localize conspecific song evolved well after the origin of hearing. The analyses revealed a novel localization mechanism wherein the geometry and structure of the tympanal membrane of each ear afford sharp sensitivity to sound arriving from a distinct angle. Females can thereby track singing males, but they only do so by following an indirect, curvilinear trajectory regularly interrupted by wide deviations.

Download or read book Real time Acoustic Source Localization with Passive Microphone Arrays written by Arden Huang and published by . This book was released on 2001 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Passive Acoustic Monitoring of Cetaceans written by Walter M. X. Zimmer and published by Cambridge University Press. This book was released on 2011-04-21 with total page 367 pages. Available in PDF, EPUB and Kindle. Book excerpt: Passive acoustic monitoring is increasingly used by the scientific community to study, survey and census marine mammals, especially cetaceans, many of which are easier to hear than to see. PAM is also used to support efforts to mitigate potential negative effects of human activities such as ship traffic, military and civilian sonar and offshore exploration. Walter Zimmer provides an integrated approach to PAM, combining physical principles, discussion of technical tools and application-oriented concepts of operations. Additionally, relevant information and tools necessary to assess existing and future PAM systems are presented, with Matlab code used to generate figures and results so readers can reproduce data and modify code to analyse the impact of changes. This allows the principles to be studied whilst discovering potential difficulties and side effects. Aimed at graduate students and researchers, the book provides all information and tools necessary to gain a comprehensive understanding of this interdisciplinary subject.

Download or read book Distributed Source Localization and Tracking Algorithms for Ad hoc Acoustic Sensor Networks written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Assessing the Performance of Omni Directional Receivers for Passive Acoustic Detection of Vocalizing Odontocetes written by and published by . This book was released on 2004 with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt: Acoustic detection and localization of marine mammals will assist mitigation efforts for various Naval and scientific missions that may impact protected species. This study sought to experimentally quantify the sonar performance of omni-directional receivers as a means to passively detect vocalizing Odontocetes in coastal waters. To accomplish this objective control led experiments using a calibrated mid-frequency sound source were conducted on the San Clemente Island Underwater Range (SCIUR) in July 2002. Six Odontocete signals were selected for transmission based upon availability and quality of archived recordings: 2 orca and 2 pilot whale whistles and sperm whale and Risso's dolphin clicks. Several hundred iterations of each signal were broadcast from R/V Point Sur at stations 300 m to 12,000 m from the range's moored three-element array. Statistical analyses were performed on the output of an energy and matched filter detector to quantify detection probability and range limits as a function of false alarm rate signal type and signal to noise ratio. The matched filter generally outperformed the energy detector with respect to the required signal to noise ratios and maximum detection range for given probabilities of detection P(D) and false alarm rate P(FA). The matched filter detected the orca2 and pilot1 whistles beyond 5000 m with a 90% P(D), 1% P(FA) and source level (SL) of 140 dB re 1 muPa. For the same conditions the orca1 and sperm whale calls were detected at 1500 m but the pilot2 and Risso's dolphin signals were not detected at the peak realized SNR of -2 dB. The energy detector had no detections with a 90% P(D) and 1% P(FA) at this -2 dB SNR, but all signals except one orca whistle were detectable beyond 1000 m with a 50% P(D) and 1% P(FA). The sperm whale was the exceptional energy detector performer with detection ranges exceeding 7 km (140 dB re 1 muPa SL) at the 50% P(D) and 1% P(FA).

Download or read book Arrays Versus Lenses as Directional Acoustic Sensors written by Fred N. Spiess and published by . This book was released on 1973 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: There are two major techniques today for creating directional acoustic sensors. These are: the use of an array of point receivers, coupled into an electrical beam forming network on the one hand and the use of a refractive lens to focus on the sound rays to a localized region on the other hand. The essential difference between these two methods lies in the way in which the transformation of a plane wave acoustic field into a diffraction limited region takes place. In the case of the lens, the actual acoustic field is modified locally by refraction and the transformation of the plane wave field into the diffraction limited region takes place within the acoustic field itself whereas the array samples the acoustic field without perturbing it and then electrically combines the samples to generate the transform of the plane wave acoustic samples into a diffraction limited signal. It is interesting to look at the implications of these differences in terms of the performance of these two techniques as directional sensors. In general there is no inherent difference in resolution or in directional response pattern between the two. In both cases the transformation which is made is aperture limited and a lens of a given, physical aperture, can have the same performance as an array of the same aperture and conversely, an array of that aperture can have the performance of a lens of a comparable aperture. Thus the differences between the two techniques must lie in other areas.

Download or read book Distributed Acoustic Localization and Tracking Design and Analysis written by Andreas Mantik Ali and published by . This book was released on 2010 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Technical Abstract Bulletin written by and published by . This book was released on 1978 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Localization and Tracking in Underwater Acoustic Networks Via High Data rate Multicarrier Communications written by Patrick Carroll and published by . This book was released on 2014 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Random Gunfire Problems and Gunshot Detection Systems written by and published by . This book was released on 1999 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: