Download or read book A Multipath Study of the Underwater Acoustic Channel with a Moving Source written by Nicholas Charles Szuchy and published by . This book was released on 1980 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Underwater Acoustic Channel written by Junying Hui and published by Springer Nature. This book was released on 2022-05-19 with total page 243 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces sonar system and acoustic channel model, average energy channel, coherent multipath channel, the theoretical basis for the stochastic time-varying space-variant channel, slowly time-varying coherent multipath channel, and reverberation channel. Based on the basic theory of underwater acoustic channels and the various characteristics of the marine acoustic environment factor, this textbook aims to help students understand the impact of the marine acoustic channel on the sonar system. It helps students to grasp underwater acoustic signal processing principles and obtain the ability to solve practical problems in underwater acoustic channel engineering. Finally, it aims at laying a foundation for the further sonar system design. This textbook is recommended for graduate or undergraduate students in the field of sonar signal processing, underwater acoustic engineering, as well as some related subjects of marine technology.
Download or read book Progress in Underwater Acoustics written by Harold Merklinger and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 815 pages. Available in PDF, EPUB and Kindle. Book excerpt: IMAGE TRACKS AT HALIFAX by L.B. Felsen All living kind much effort spend Some model modes, some model rays, To cope with their environment Some feel that spectra all portrays. Some use their eyes, some use their nose Then there are those who with despatch, To sense where other things repose. Take refuge in the ocean wedge. For one group, nothing's more profound Than to explore the world with sound. If things get messy, randomize. These audio diagnosticians What's partly smooth, determinize. You ponder, is it this or that? Go by the name of acousticians. And wish you were a lowly bat They regularly meet to check Whether their sonogram's on track. The meeting's hosts did treat us well. With images stored in their packs, They let the climate cast its spell. This year they came to Halifax. No weath'ry hope was placed in vain. There they combined with ocean types We were exposed to wind and rain, And each could hear the other's gripes. We glimpsed blue sky through clouds dispersed. A meeting naturally does start But rainy sequence was reversed: Reviewing present state of art. The ocean types would like it wet What we found out is where it's at: Yet they got stuck with sun instead. We cannot hope to match the bat Each confrence has the same refrain: Computer printouts by the reams It has been fun to meet again.
Download or read book Digital Underwater Acoustic Communications written by Lufen Xu and published by Academic Press. This book was released on 2016-09-16 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Digital Underwater Acoustic Communications focuses on describing the differences between underwater acoustic communication channels and radio channels, discusses loss of transmitted sound in underwater acoustic channels, describes digital underwater acoustic communication signal processing, and provides a comprehensive reference to digital underwater acoustic communication equipment. This book is designed to serve as a reference for postgraduate students and practicing engineers involved in the design and analysis of underwater acoustic communications systems as well as for engineers involved in underwater acoustic engineering. Introduces the basics of underwater acoustics, along with the advanced functionalities needed to achieve reliable communications in underwater environment Identifies challenges in underwater acoustic channels relative to radio channels, underwater acoustic propagation, and solutions Shows how multi-path structures can be thought of as time diversity signals Presents a new, robust signal processing system, and an advanced FH-SS system for multimedia underwater acoustic communications with moderate communication ranges (above 20km) and rates (above 600bps) Describes the APNFM system for underwater acoustic communication equipment (including both civil and military applications), to be employed in active sonar to improve its performance
Download or read book The Shock and Vibration Digest written by and published by . This book was released on 1986 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Underwater Acoustic Channel Estimation Using Multiple Sources and Receivers in Shallow Waters at Very high Frequencies written by Samar Kaddouri and published by . This book was released on 2015 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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 quantiably 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. This dissertation proposes two robust channel estimation techniques for simultaneous transmissions using multiple sources and multiple receivers (MIMO) that closely follows the rapidly time-varying nature of the underwater channel. The first method is a trended least square (LS) estimation that combines the traditional LS method with an empirical modal decomposition (EMD) based trend extraction algorithm. This method allows separating the slow fading modes in the MIMO channels from the fast-fading ones and thus achieves a close tracking of the channel impulse response time fluctuations. This dissertation also outlines a time-varying underwater channel estimation method based on the channel sparsity characteristic. The sparsity of the underwater communication channel is exploited by using the MIMO P-iterative greedy orthogonal matching pursuit (MIMO-OMP) algorithm for the channel estimation. Both techniques are demonstrated in a fully controlled environment, using simulated and experimental data. To test the proposed channel estimation techniques, an acoustic model for a MIMO channel is developed using the method of images applied to a completely closed three-dimensional duct with a pressure release surface boundary and five rigid walls. The MIMO simulated channel provides the strength and delay of all echoes forming the channel. Both simulation and experimental results show a signicant improvement in the estimation of the channel impulse response, thus validating the two proposed algorithms.
Download or read book Open File Report written by and published by . This book was released on 1983 with total page 202 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 Underwater Acoustic Sensor Networks written by Yang Xiao and published by CRC Press. This book was released on 2010-05-19 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt: A detailed review of underwater channel characteristics, Underwater Acoustic Sensor Networks investigates the fundamental aspects of underwater communication. Prominent researchers from around the world consider contemporary challenges in the development of underwater acoustic sensor networks (UW-ASNs) and introduce a cross-layer approach for effec
Download or read book Advances in Environment Research and Application 2012 Edition written by and published by ScholarlyEditions. This book was released on 2012-12-26 with total page 1179 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Environment Research and Application / 2012 Edition is a ScholarlyEditions™ eBook that delivers timely, authoritative, and comprehensive information about Environment. The editors have built Advances in Environment Research and Application / 2012 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about Environment in this eBook to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Advances in Environment Research and Application / 2012 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.
Download or read book Curricula in the Atmospheric and Oceanographic Sciences written by and published by . This book was released on 1982 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Accuracy in Locating an Underwater Acoustic Source in a Multipath Environment microform written by Brian Lyle Frank Daku and published by National Library of Canada = Bibliothèque nationale du Canada. This book was released on 1990 with total page 193 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book European Conference on Underwater Acoustics written by M. Weydert and published by CRC Press. This book was released on 2004-01-14 with total page 786 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book represents the proceedings of the Conference on Underwater Acoustics, held in September 1992, to bring together all the various disciplines involved in a forum to present the latest research on all aspects of marine acoustics.
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 Waves in Layered Media written by L Brekhovskikh and published by Elsevier. This book was released on 2012-12-02 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt: Waves in Layered Media discusses different theories about the relationship between waves and media. The book specifically covers several factors that can affect the behavior and formation of various kinds of waves in different types of media. Comprised of nine chapters, the book establishes the fundamentals by first tackling simplest concepts, such as the behavior plane wave and discretely layered media. The succeeding chapters cover much more complex ideas, such as the refraction and reflection of waves, spherical wave, and wave in inhomogeneous media. The book will be a great asset to researchers whose work involves acoustics, or to professionals whose line of work involves sound waves.
Download or read book The Journal of the Acoustical Society of America written by and published by . This book was released on 2009 with total page 764 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Novel Adaptive Signal Processing Techniques for Underwater Acoustic Communications written by and published by . This book was released on 2011 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt:
