Mobile Ad Hoc Networking

Download Mobile Ad Hoc Networking PDF Online Free

Author :
Publisher : John Wiley & Sons
ISBN 13 : 1118511239
Total Pages : 690 pages
Book Rating : 4.1/5 (185 download)

DOWNLOAD NOW!


Book Synopsis Mobile Ad Hoc Networking by : Stefano Basagni

Download or read book Mobile Ad Hoc Networking written by Stefano Basagni and published by John Wiley & Sons. This book was released on 2013-02-07 with total page 690 pages. Available in PDF, EPUB and Kindle. Book excerpt: "An excellent book for those who are interested in learning the current status of research and development . . . [and] who want to get a comprehensive overview of the current state-of-the-art." —E-Streams This book provides up-to-date information on research and development in the rapidly growing area of networks based on the multihop ad hoc networking paradigm. It reviews all classes of networks that have successfully adopted this paradigm, pointing out how they penetrated the mass market and sparked breakthrough research. Covering both physical issues and applications, Mobile Ad Hoc Networking: Cutting Edge Directions offers useful tools for professionals and researchers in diverse areas wishing to learn about the latest trends in sensor, actuator, and robot networking, mesh networks, delay tolerant and opportunistic networking, and vehicular networks. Chapter coverage includes: Multihop ad hoc networking Enabling technologies and standards for mobile multihop wireless networking Resource optimization in multiradio multichannel wireless mesh networks QoS in mesh networks Routing and data dissemination in opportunistic networks Task farming in crowd computing Mobility models, topology, and simulations in VANET MAC protocols for VANET Wireless sensor networks with energy harvesting nodes Robot-assisted wireless sensor networks: recent applications and future challenges Advances in underwater acoustic networking Security in wireless ad hoc networks Mobile Ad Hoc Networking will appeal to researchers, developers, and students interested in computer science, electrical engineering, and telecommunications.

Advances inUnderwater Acoustics

Download Advances inUnderwater Acoustics PDF Online Free

Author :
Publisher : BoD – Books on Demand
ISBN 13 : 9535136097
Total Pages : 146 pages
Book Rating : 4.5/5 (351 download)

DOWNLOAD NOW!


Book Synopsis Advances inUnderwater Acoustics by : Andrzej Zak

Download or read book Advances inUnderwater Acoustics written by Andrzej Zak and published by BoD – Books on Demand. This book was released on 2017-11-22 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: Underwater acoustics, despite the relatively short history, has already found practical application in many areas of human activity. It allows, among others, depth research, data transmission, and underwater observation and provides maritime transport safety and security against terrorists. Moreover, underwater acoustic technologies are also widely used in medicine, biology, and many other fields. Therefore, it is one of the most developing areas. This book is a collection of experiences of scientists from around the world engaged in research, design, and construction, as well as the daily use of underwater acoustic systems. Giving this book in the hands of the reader, we hope that it will be a treasure trove of knowledge and inspiration for further research in the field of underwater acoustics.

Digital Sonar Design in Underwater Acoustics

Download Digital Sonar Design in Underwater Acoustics PDF Online Free

Author :
Publisher : Springer Science & Business Media
ISBN 13 : 3642182909
Total Pages : 658 pages
Book Rating : 4.6/5 (421 download)

DOWNLOAD NOW!


Book Synopsis Digital Sonar Design in Underwater Acoustics by : Qihu Li

Download or read book Digital Sonar Design in Underwater Acoustics written by Qihu Li and published by Springer Science & Business Media. This book was released on 2012-03-05 with total page 658 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Digital Sonar Design in Underwater Acoustics Principles and Applications" provides comprehensive and up-to-date coverage of research on sonar design, including the basic theory and techniques of digital signal processing, basic concept of information theory, ocean acoustics, underwater acoustic signal propagation theory, and underwater signal processing theory. This book discusses the general design procedure and approaches to implementation, the design method, system simulation theory and techniques, sonar tests in the laboratory, lake and sea, and practical validation criteria and methods for digital sonar design. It is intended for researchers in the fields of underwater signal processing and sonar design, and also for navy officers and ocean explorers. Qihu Li is a professor at the Institute of Acoustics, Chinese Academy of Sciences, and an academician of the Chinese Academy of Sciences.

Sonar and Underwater Acoustics

Download Sonar and Underwater Acoustics PDF Online Free

Author :
Publisher : John Wiley & Sons
ISBN 13 : 1118600657
Total Pages : 590 pages
Book Rating : 4.1/5 (186 download)

DOWNLOAD NOW!


Book Synopsis Sonar and Underwater Acoustics by : Jean-Paul Marage

Download or read book Sonar and Underwater Acoustics written by Jean-Paul Marage and published by John Wiley & Sons. This book was released on 2013-02-07 with total page 590 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sonar and Underwater Acoustics brings together all the concepts necessary for designers and users of sonar systems. Unlike other books on this subject, which are often too specialized, this book is accessible to a wider audience. The first part focuses on the acoustic environment, antenna structures, and electric acoustic interface. The latter provides knowledge required to design, as well as the development and implementation of chain processes for an active sonar from the conditioning input to output processing. The reader will find a comprehensive range of all problems encountered in underwater acoustics for a sonar application, from physical phenomena governing the environment and the corresponding constraints, through to the technical definition of transducers and antennas, and the types of signal processing involved. In one section, measures in underwater acoustics are also proposed.

Underwater Acoustics and Ocean Dynamics

Download Underwater Acoustics and Ocean Dynamics PDF Online Free

Author :
Publisher : Springer
ISBN 13 : 9811024227
Total Pages : 127 pages
Book Rating : 4.8/5 (11 download)

DOWNLOAD NOW!


Book Synopsis Underwater Acoustics and Ocean Dynamics by : Lisheng Zhou

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 127 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.

Underwater Acoustic Modeling and Simulation

Download Underwater Acoustic Modeling and Simulation PDF Online Free

Author :
Publisher : CRC Press
ISBN 13 : 1466564946
Total Pages : 521 pages
Book Rating : 4.4/5 (665 download)

DOWNLOAD NOW!


Book Synopsis Underwater Acoustic Modeling and Simulation by : Paul C. Etter

Download or read book Underwater Acoustic Modeling and Simulation written by Paul C. Etter and published by CRC Press. This book was released on 2017-12-19 with total page 521 pages. Available in PDF, EPUB and Kindle. Book excerpt: Underwater Acoustic Modeling and Simulation, Fourth Edition continues to provide the most authoritative overview of currently available propagation, noise, reverberation, and sonar-performance models. This fourth edition of a bestseller discusses the fundamental processes involved in simulating the performance of underwater acoustic systems and emphasizes the importance of applying the proper modeling resources to simulate the behavior of sound in virtual ocean environments. New to the Fourth Edition Extensive new material that addresses recent advances in inverse techniques and marine-mammal protection Problem sets in each chapter Updated and expanded inventories of available models Designed for readers with an understanding of underwater acoustics but who are unfamiliar with the various aspects of modeling, the book includes sufficient mathematical derivations to demonstrate model formulations and provides guidelines for selecting and using the models. Examples of each type of model illustrate model formulations, model assumptions, and algorithm efficiency. Simulation case studies are also included to demonstrate practical applications. Providing a thorough source of information on modeling resources, this book examines the translation of our physical understanding of sound in the sea into mathematical models that simulate acoustic propagation, noise, and reverberation in the ocean. The text shows how these models are used to predict and diagnose the performance of complex sonar systems operating in the undersea environment.

Underwater Acoustic Digital Signal Processing and Communication Systems

Download Underwater Acoustic Digital Signal Processing and Communication Systems PDF Online Free

Author :
Publisher : Springer Science & Business Media
ISBN 13 : 1475736177
Total Pages : 283 pages
Book Rating : 4.4/5 (757 download)

DOWNLOAD NOW!


Book Synopsis Underwater Acoustic Digital Signal Processing and Communication Systems by : Robert Istepanian

Download or read book Underwater Acoustic Digital Signal Processing and Communication Systems written by Robert Istepanian and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 283 pages. Available in PDF, EPUB and Kindle. Book excerpt: Underwater acoustic digital signal processing and communications is an area of applied research that has witnessed major advances over the past decade. Rapid developments in this area were made possible by the use of powerful digital signal processors (DSPs) whose speed, computational power and portability allowed efficient implementation of complex signal processing algorithms and experimental demonstration of their performance in a variety of underwater environments. The early results served as a motivation for the development of new and improved signal processing methods for underwater applications, which today range from classical of autonomous underwater vehicles and sonar signal processing, to remote control underwater wireless communications. This book presents the diverse areas of underwater acoustic signal processing and communication systems through a collection of contributions from prominent researchers in these areas. Their results, both new and those published over the past few years, have been assembled to provide what we hope is a comprehensive overview of the recent developments in the field. The book is intended for a general audience of researchers, engineers and students working in the areas of underwater acoustic signal processing. It requires the reader to have a basic understanding of the digital signal processing concepts. Each topic is treated from a theoretical perspective, followed by practical implementation details. We hope that the book can serve both as a study text and an academic reference.

Computational Ocean Acoustics

Download Computational Ocean Acoustics PDF Online Free

Author :
Publisher : Springer Science & Business Media
ISBN 13 : 1441986782
Total Pages : 808 pages
Book Rating : 4.4/5 (419 download)

DOWNLOAD NOW!


Book Synopsis Computational Ocean Acoustics by : Finn B. Jensen

Download or read book Computational Ocean Acoustics written by Finn B. Jensen and published by Springer Science & Business Media. This book was released on 2011-06-10 with total page 808 pages. Available in PDF, EPUB and Kindle. Book excerpt: Senior level/graduate level text/reference presenting state-of-the- art numerical techniques to solve the wave equation in heterogeneous fluid-solid media. Numerical models have become standard research tools in acoustic laboratories, and thus computational acoustics is becoming an increasingly important branch of ocean acoustic science. The first edition of this successful book, written by the recognized leaders of the field, was the first to present a comprehensive and modern introduction to computational ocean acoustics accessible to students. This revision, with 100 additional pages, completely updates the material in the first edition and includes new models based on current research. It includes problems and solutions in every chapter, making the book more useful in teaching (the first edition had a separate solutions manual). The book is intended for graduate and advanced undergraduate students of acoustics, geology and geophysics, applied mathematics, ocean engineering or as a reference in computational methods courses, as well as professionals in these fields, particularly those working in government (especially Navy) and industry labs engaged in the development or use of propagating models.

Underwater Acoustics

Download Underwater Acoustics PDF Online Free

Author :
Publisher : John Wiley & Sons
ISBN 13 : 1119957494
Total Pages : 386 pages
Book Rating : 4.1/5 (199 download)

DOWNLOAD NOW!


Book Synopsis Underwater Acoustics by : Richard P. Hodges

Download or read book Underwater Acoustics written by Richard P. Hodges and published by John Wiley & Sons. This book was released on 2011-06-28 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: Offering complete and comprehensive coverage of modern sonar spectrum system analysis, Underwater Acoustics: Analysis, Design and Performance of Sonar provides a state-of-the-art introduction to the subject and has been carefully structured to offer a much-needed update to the classic text by Urick. Expanded to included computational approaches to the topic, this book treads the line between the highly theoretical and mathematical texts and the more populist, non-mathematical books that characterize the existing literature in the field. The author compares and contrasts different techniques for sonar design, analysis and performance prediction and includes key experimental and theoretical results, pointing the reader towards further detail with extensive references. Practitioners in the field of sonar design, analysis and performance prediction as well as graduate students and researchers will appreciate this new reference as an invaluable and timely contribution to the field. Chapters include the sonar equation, radiated, self and ambient noise, active sonar sources, transmission loss, reverberation, transducers, active target strength, statistical detection theory, false alarms, contacts and targets, variability and uncertainty, modelling detections and tactical decision aids, cumulative probability of detection, tracking target motion analysis and localization, and design and evaluation of sonars

Progress in Underwater Acoustics

Download Progress in Underwater Acoustics PDF Online Free

Author :
Publisher : Springer Science & Business Media
ISBN 13 : 1461318718
Total Pages : 815 pages
Book Rating : 4.4/5 (613 download)

DOWNLOAD NOW!


Book Synopsis Progress in Underwater Acoustics by : Harold Merklinger

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.

An Introduction to Underwater Acoustics

Download An Introduction to Underwater Acoustics PDF Online Free

Author :
Publisher : Springer Science & Business Media
ISBN 13 : 9783540429678
Total Pages : 386 pages
Book Rating : 4.4/5 (296 download)

DOWNLOAD NOW!


Book Synopsis An Introduction to Underwater Acoustics by : Xavier Lurton

Download or read book An Introduction to Underwater Acoustics written by Xavier Lurton and published by Springer Science & Business Media. This book was released on 2002 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presented in a clear and concise way as an introductory text and practical handbook, the book provides the basic physical phenomena governing underwater acoustical waves, propagation, reflection, target backscattering and noise. It covers the general features of sonar systems, transducers and arrays, signal processing and performance evaluation. It provides an overview of today's applications, presenting the working principles of the various systems. From the reviews: "Presented in a clear and concise way as an introductory text and practical handbook, the book provides the basic physical phenomena governing underwater acoustical waves, propagation, reflection, target backscattering and noise. ⦠It provides an overview of todayâs applications, presenting the working principles of the various systems." (Oceanis, Vol. 27 (3-4), 2003) "This book is a general survey of Underwater Acoustics, intended to make the subject âas easily accessible as possible, with a clear emphasis on applications.â In this the author has succeeded, with a wide variety of subjects presented with minimal derivation ⦠. There is an emphasis on technology and on intuitive physical explanation ⦠." (Darrell R. Jackson, Journal of the Acoustic Society of America, Vol. 115 (2), February, 2004) "This is an exciting new scientific publication. It is timely and welcome ⦠. Furthermore, it is up to date and readable. It is well researched, excellently published and ranks with earlier books in this discipline ⦠. Many persons in the marine science field including acousticians, hydrographers, oceanographers, fisheries scientists, engineers, educators, students ⦠and equipment manufacturers will benefit greatly by reading all or part of this text. The author is to be congratulated on his fine contribution ⦠." (Stephen B. MacPhee, International Hydrographic Review, Vol. 4 (2), 2003)

Applied Underwater Acoustics

Download Applied Underwater Acoustics PDF Online Free

Author :
Publisher : Elsevier
ISBN 13 : 0128112476
Total Pages : 980 pages
Book Rating : 4.1/5 (281 download)

DOWNLOAD NOW!


Book Synopsis Applied Underwater Acoustics by : Thomas Neighbors

Download or read book Applied Underwater Acoustics written by Thomas Neighbors and published by Elsevier. This book was released on 2017-01-19 with total page 980 pages. Available in PDF, EPUB and Kindle. Book excerpt: Applied Underwater Acoustics meets the needs of scientists and engineers working in underwater acoustics and graduate students solving problems in, and preparing theses on, topics in underwater acoustics. The book is structured to provide the basis for rapidly assimilating the essential underwater acoustic knowledge base for practical application to daily research and analysis. Each chapter of the book is self-supporting and focuses on a single topic and its relation to underwater acoustics. The chapters start with a brief description of the topic’s physical background, necessary definitions, and a short description of the applications, along with a roadmap to the chapter. The subtopics covered within individual subchapters include most frequently used equations that describe the topic. Equations are not derived, rather, assumptions behind equations and limitations on the applications of each equation are emphasized. Figures, tables, and illustrations related to the sub-topic are presented in an easy-to-use manner, and examples on the use of the equations, including appropriate figures and tables are also included. Provides a complete and up-to-date treatment of all major subjects of underwater acoustics Presents chapters written by recognized experts in their individual field Covers the fundamental knowledge scientists and engineers need to solve problems in underwater acoustics Illuminates, in shorter sub-chapters, the modern applications of underwater acoustics that are described in worked examples Demands no prior knowledge of underwater acoustics, and the physical principles and mathematics are designed to be readily understood by scientists, engineers, and graduate students of underwater acoustics Includes a comprehensive list of literature references for each chapter

Adaptive Methods in Underwater Acoustics

Download Adaptive Methods in Underwater Acoustics PDF Online Free

Author :
Publisher : Springer Science & Business Media
ISBN 13 : 9400953615
Total Pages : 763 pages
Book Rating : 4.4/5 (9 download)

DOWNLOAD NOW!


Book Synopsis Adaptive Methods in Underwater Acoustics by : H.G. Urban

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.

OFDM for Underwater Acoustic Communications

Download OFDM for Underwater Acoustic Communications PDF Online Free

Author :
Publisher : John Wiley & Sons
ISBN 13 : 1118693817
Total Pages : 498 pages
Book Rating : 4.1/5 (186 download)

DOWNLOAD NOW!


Book Synopsis OFDM for Underwater Acoustic Communications by : Sheng Zhou

Download or read book OFDM for Underwater Acoustic Communications written by Sheng Zhou and published by John Wiley & Sons. This book was released on 2014-03-21 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt: A blend of introductory material and advanced signal processing and communication techniques, of critical importance to underwater system and network development This book, which is the first to describe the processing techniques central to underwater OFDM, is arranged into four distinct sections: First, it describes the characteristics of underwater acoustic channels, and stresses the difference from wireless radio channels. Then it goes over the basics of OFDM and channel coding. The second part starts with an overview of the OFDM receiver, and develops various modules for the receiver design in systems with single or multiple transmitters. This is the main body of the book. Extensive experimental data sets are used to verify the receiver performance. In the third part, the authors discuss applications of the OFDM receiver in i) deep water channels, which may contain very long separated multipath clusters, ii) interference-rich environments, where an unintentional interference such as Sonar will be present, and iii) a network with multiple users where both non-cooperative and cooperative underwater communications are developed. Lastly, it describes the development of a positioning system with OFDM waveforms, and the progress on the OFDM modem development. Closely related industries include the development and manufacturing of autonomous underwater vehicles (AUVs) and scientific sensory equipment. AUVs and sensors in the future could integrate modems, based on the OFDM technology described in this book. Contents includes: Underwater acoustic channel characteristics/OFDM basics/Peak-to-average-ratio control/Detection and Doppler estimation (Doppler scale and CFO)/Channel estimation and noise estimation/A block-by-block progressive receiver and performance results/Extensions to multi-input multi-output OFDM/Receiver designs for multiple users/Cooperative underwater OFDM (Physical layer network coding and dynamic coded cooperation)/Localization with OFDM waveforms/Modem developments A valuable resource for Graduate and postgraduate students on electrical engineering or physics courses; electrical engineers, underwater acousticians, communications engineers

Springer Handbook of Acoustics

Download Springer Handbook of Acoustics PDF Online Free

Author :
Publisher : Springer Science & Business Media
ISBN 13 : 0387304460
Total Pages : 1179 pages
Book Rating : 4.3/5 (873 download)

DOWNLOAD NOW!


Book Synopsis Springer Handbook of Acoustics by : Thomas Rossing

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.

Recent Advances in Underwater Acoustics

Download Recent Advances in Underwater Acoustics PDF Online Free

Author :
Publisher :
ISBN 13 : 9781873082058
Total Pages : 256 pages
Book Rating : 4.0/5 (82 download)

DOWNLOAD NOW!


Book Synopsis Recent Advances in Underwater Acoustics by :

Download or read book Recent Advances in Underwater Acoustics written by and published by . This book was released on 1991 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Digital Underwater Acoustic Communications

Download Digital Underwater Acoustic Communications PDF Online Free

Author :
Publisher : Academic Press
ISBN 13 : 0128030291
Total Pages : 290 pages
Book Rating : 4.1/5 (28 download)

DOWNLOAD NOW!


Book Synopsis Digital Underwater Acoustic Communications by : Lufen Xu

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 290 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