Download or read book Adaptive Methods in Underwater Acoustics written by H.G. Urban and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 763 pages. Available in PDF, EPUB and Kindle. Book excerpt: The NATO Advanced Study Institute on Adaptive Methods in Underwater Acoustics was held on 30 July - 10 August 1984 in LLineburg, Germany. The Institute was primarily concerned with signal processing for underwater appl ica tions. The majority of the presentations, when taken together, yield a definite picture of the present status of understanding of adaptive and high resolution processing, setting out the progress achieved over the past four years together with the major problem areas remaining. Major effort was made to obtain a commensurate contribution of tutorial and advanced research papers. It is my hope that the material in this volume may be equally well suited for students getting an introduction to some of the basic problems in underwater signal processing and for the professionals who may obtain an up-to-date overview of the present state of the art. This might be especially useful in view of the controversy and lack of adequate interrelationships which have marked this rapidly expanding field in the past. Practical reinforcement of this picture is provided by the material concerning digital and optical processing technology, giving some guidance to achievable adaptive and high resolution techniques with current processing devices. The formal programme was extended and detailed by a series of six evening work shops on specific topics, during which informal discussions took place among the participants. Summaries of these workshops are also included in these Proceedings.
Download or read book Adaptive Methods in Underwater Acoustics written by H. G. Urban and published by . This book was released on 1985-04-30 with total page 804 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Adaptive Methods in Underwater Acoustics written by Advanced Study Institute on Adaptive Methods in Underwater Acoustics. 1984, Lüneburg and published by . This book was released on 1985 with total page 785 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Research on Adaptive and Machine Learning Methods in Underwater Acoustic Channel Estimation written by Yonglin Zhang and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ocean covers more than 70% of the earth, which provides rich biological, chemical, mineral and space resources for the development of human civilization. The cause of managing the ocean is of strategic importance to our economic development and national security. Acoustic wave is the most widely used and mature underwater information transmission carrier known to mankind. Underwater acoustic (UWA) communication technology is one of the main technical supports to carry out various marine activities, but it is challenged by the complex marine environment, specifically in terms of propagation loss, UWA environmental noise, multipath propagation characteristics, Doppler expansion, spatial and temporal variation effects and other scientific issues, which restricts the improvements of the bit error rate (BER) performance, communication rate, communication distance, robustness and other indicators. The current level of development of UWA communication technology is difficult to fully meet the needs of practical applications.Channel estimation is an effective technical means to solve the problems of multipath effect and temporal- spatial variation characteristics. Recent breakthroughs in adaptive methods and machine learning in various fields have brought new opportunities for the further development of UWA channel estimation technology, but also raised new technical problems, such as the use of channel structure characteristics, sample scarcity training, label missing training, domain mismatch caused by environmental changes. These problems make the effectiveness and applicability of the new method seriously restricted, and it is difficult to bring out the proper information sensing ability.Based on the frontier of intelligent ocean and marine information science, this thesis focuses on the scientific problems of UWA communication in complex marine environment according to the development needs of national marine strategy, aims at the key technical problems faced by adaptive and machine learning channel estimation methods, such as analysis of channel cluster sparsity characteristics, limited data, label missing, domain mismatch, etc., and introduces optimization methods, neural network model design and analysis, data augmentation methods, transfer learning and other recent academic results. We have explored the mechanism of adaptive and machine learning based channel estimation methods and finally proposed a series of new methods for channel estimation based on adaptive signal processing and machine learning.
Download or read book Underwater Acoustics written by Salah Bourennane and published by BoD – Books on Demand. This book was released on 2012-03-28 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: The field of acoustic engineering has many various potential applications, such as in ocean science research and homeland security. This book provides cutting-edge knowledge in current techniques and technologies, such as the adaptive technique for underwater communication, array processing and the CI/OFDM system. One chapter takes inspiration from the natural world in proposing a new bio-inspired ranging approach for resolution purposes. Technologies such as high-resolution array processing methods can also be used to locate underwater objects in sediment, as one chapter shows. Finally, two contributions cover the applications of narrowband interference suppression and iterative equalization, and decoding schemes. Given the scope of the book, it will be required reading for researchers and engineers in the field.
Download or read book NATO Advanced Study Institute on Adaptive Methods in Underwater Acoustics written by North Atlantic Treaty Organization. Scientific Affairs Division and published by . This book was released on 1984* with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High resolution Methods in Underwater Acoustics written by Michel Bouvet and published by Springer. This book was released on 1991 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Adaptive Technique for Underwater Acoustic Communication written by Shen Xiaohong and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Adaptive Technique for Underwater Acoustic Communication.
Download or read book Underwater Acoustic Data Processing written by Y. T. Chan and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 642 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains the papers that were accepted for presentation at the 1988 NATO Advanced Study Institute on Underwater Acoustic Data Processing, held at the Royal Military College of Canada from 18 to 29 July, 1988. Approximately 110 participants from various NATO countries were in attendance during this two week period. Their research interests range from underwater acoustics to signal processing and computer science; some are renowned scientists and some are recent Ph.D. graduates. The purpose of the ASI was to provide an authoritative summing up of the various research activities related to sonar technology. The exposition on each subject began with one or two tutorials prepared by invited lecturers, followed by research papers which provided indications of the state of development in that specific area. I have broadly classified the papers into three sections under the titles of I. Propagation and Noise, II. Signal Processing and III. Post Processing. The reader will find in Section I papers on low frequency acoustic sources and effects of the medium on underwater acoustic propagation. Problems such as coherence loss due to boundary interaction, wavefront distortion and multipath transmission were addressed. Besides the medium, corrupting noise sources also have a strong influence on the performance of a sonar system and several researchers described methods of modeling these sources.
Download or read book Cognitive Underwater Acoustic Networking Techniques written by Dimitri Sotnik and published by Springer Nature. This book was released on 2020-09-29 with total page 89 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book summarizes the latest research on cognitive network-layer methods and smart adaptive physical-layer methods in underwater networks. Underwater communication requires extendable and delay-tolerant underwater acoustic networks capable of supporting multiple frequency bands, data rates and transmission ranges. The book also discusses a suitable foreground communication stack for mixed mobile/static networks, a technology that requires adaptive physical layer waveforms and cognitive network strategies with underlying cooperative and non-cooperative robust processes. The goal is to arrive at a universally applicable standard in the area of Underwater Internet-of-Things [ISO/IEC 30140, 30142, 30143]. The book is the second spin-off of the research project RACUN, after the first RACUN-book "Underwater Acoustic Networking Techniques" (https://link.springer.com/book/10.1007%2F978-3-642-25224-2)
Download or read book Underwater Acoustics and Ocean Dynamics written by Lisheng Zhou and published by Springer. This book was released on 2016-10-17 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: These proceedings are a collection of 16 selected scientific papers and reviews by distinguished international experts that were presented at the 4th Pacific Rim Underwater Acoustics Conference (PRUAC), held in Hangzhou, China in October 2013. The topics discussed at the conference include internal wave observation and prediction; environmental uncertainty and coupling to sound propagation; environmental noise and ocean dynamics; dynamic modeling in acoustic fields; acoustic tomography and ocean parameter estimation; time reversal and matched field processing; underwater acoustic localization and communication as well as measurement instrumentations and platforms. These proceedings provide insights into the latest developments in underwater acoustics, promoting the exchange of ideas for the benefit of future research.
Download or read book High resolution Spatial Processing in Underwater Acoustics written by Ronald A. Wagstaff and published by . This book was released on 1985 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Springer Handbook of Acoustics written by Thomas Rossing and published by Springer Science & Business Media. This book was released on 2007-06-21 with total page 1179 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is an unparalleled modern handbook reflecting the richly interdisciplinary nature of acoustics edited by an acknowledged master in the field. The handbook reviews the most important areas of the subject, with emphasis on current research. The authors of the various chapters are all experts in their fields. Each chapter is richly illustrated with figures and tables. The latest research and applications are incorporated throughout, including computer recognition and synthesis of speech, physiological acoustics, diagnostic imaging and therapeutic applications and acoustical oceanography. An accompanying CD-ROM contains audio and video files.
Download or read book Aspects of Signal Processing written by G. Tacconi and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 413 pages. Available in PDF, EPUB and Kindle. Book excerpt: The summer school held in Portovenere followed a tutorial format with the purpose of familiarizing postdoctoral or postgraduate students in the basic theories and up-to-date applications of present knowledge. Although, from a teaching point of view, a certain areount of overlapping is always useful, in order to avoid excessive duplication direct contact between lecturers expert in the same subject was encouraged during the preparation phase. In recent years computer facilities and theoretical implementa tion have considerably increased the possibility of solving problems relating to signal detection in noise. Any type of communication may take advantage of signal processing principles, including any type of physical measurement that can be considered as a non-semantic and/or quasi-semantic communication. Since signal processing techniques are common to many branches of science (telecommunications, radar, sonar, seismology, geophysics, nuclear research, space research and others), the advanced and sophisticated levels reached singularly in anyone of them could be used to the advantage of the others. In particular, underwater acoustics is a discipline which, to some extent, represents a practical general model that has permitted the development of signal processing techniques suitable to meet data reduction and interpretation needs of other branches of science. This ASI consequently underlined the inter-disciplinarity of signal proces sing in order that the principles of outstanding methods developed in one field may be adapted to others.
Download or read book Adaptive Modulation Techniques for Underwater Acoustic Channels written by Sanjay Mani and published by . This book was released on 2008 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Self adaptive Methods for Acoustic Focusing and Mode Extraction in a Shallow Ocean Waveguide written by Shane C. Walker and published by . This book was released on 2005 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: Acoustic propagation in shallow water environments is dominated by interactions with the air/water and water/sediment interfaces, leading to complicated spatio-temporal behavior of the acoustic field. This complexity has proven challenging to the development of shallow ocean acoustic detection, communication, and tomographic applications. One approach to shallow ocean acoustics has been to combine the physics of waveguides with thorough measurement and characterization of the propagation environment to generate accurate acoustic models. However, the costs of characterizing the environment often prove prohibitive. This dissertation develops self-adaptive methods for use in shallow ocean acoustic applications that require no a-priori knowledge of the environment. In contrast to past trends that viewed the complexity of the shallow ocean as a burden, these self-adaptive techniques capitalize on the diversity of the propagation medium. Methods are developed for using vertical geometry acoustic transducer arrays to extract information from the sampled acoustic fields in a range-independent environment. In one scenario, the acoustic response sampled between a pair of arrays is iterated to generate an estimate for the response at longer ranges. In another scenario, a single array is used to extract the modes of acoustic propagation in a range-independent waveguide using a single, partial water column spanning vertical array of acoustic transducers. The mode extraction method is applied to both an ensemble of stationary broadband sources as well as a moving narrowband source subject to arbitrary accelerations. These methods are combined with existing time-reversal techniques to produce a high resolution acoustic focus at an arbitrary location in the shallow ocean waveguide. Simulation, laboratory and at sea experiments support the theory. Though acoustic imaging applications are emphasized in this work, these methods may prove useful for both communications and tomography applications as well.
Download or read book Analysis of and Techniques for Adaptive Equalization for Underwater Acoustic Communication written by Ballard Justin Smith Blair and published by . This book was released on 2011 with total page 215 pages. Available in PDF, EPUB and Kindle. Book excerpt: Underwater wireless communication is quickly becoming a necessity for applications in ocean science, defense, and homeland security. Acoustics remains the only practical means of accomplishing long-range communication in the ocean. The acoustic communication channel is fraught with difficulties including limited available bandwidth, long delay-spread, time-variability, and Doppler spreading. These difficulties reduce the reliability of the communication system and make high data-rate communication challenging. Adaptive decision feedback equalization is a common method to compensate for distortions introduced by the underwater acoustic channel. Limited work has been done thus far to introduce the physics of the underwater channel into improving and better understanding the operation of a decision feedback equalizer. This thesis examines how to use physical models to improve the reliability and reduce the computational complexity of the decision feedback equalizer. The specific topics covered by this work are: how to handle channel estimation errors for the time varying channel, how to use angular constraints imposed by the environment into an array receiver, what happens when there is a mismatch between the true channel order and the estimated channel order, and why there is a performance difference between the direct adaptation and channel estimation based methods for computing the equalizer coefficients. For each of these topics, algorithms are provided that help create a more robust equalizer with lower computational complexity for the underwater channel.
