Download or read book Analysis and Optimization of OFDM Underwater Acoustic Communications written by Xiaopeng Huang and published by . This book was released on 2011 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Underwater Acoustic OFDM written by Lei Wan and published by . This book was released on 2014 with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cooperative OFDM Underwater Acoustic Communications written by Xilin Cheng and published by Springer. This book was released on 2016-06-03 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: Following underwater acoustic channel modeling, this book investigates the relationship between coherence time and transmission distances. It considers the power allocation issues of two typical transmission scenarios, namely short-range transmission and medium-long range transmission. For the former scenario, an adaptive system is developed based on instantaneous channel state information. The primary focus is on cooperative dual-hop orthogonal frequency division multiplexing (OFDM).This book includes the decomposed fountain codes designed to enable reliable communications with higher energy efficiency. It covers the Doppler Effect, which improves packet transmission reliability for effective low-complexity mirror-mapping-based intercarrier interference cancellation schemes capable of suppressing the intercarrier interference power level. Designed for professionals and researchers in the field of underwater acoustic communications, this book is also suitable for advanced-level students in electrical engineering or computer science.
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
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 Spectrally Efficient Underwater Acoustic Communications written by Andreja Radošević and published by . This book was released on 2012 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this dissertation, we consider design aspects of spectrally efficient underwater acoustic (UWA) communications. In particular, we first focus on statistical characterization and capacity evaluation of shallow water acoustic communications channels. Wideband single-carrier and multi-carrier probe signals are employed during the Kauai Acoustic Communications MURI 2008 (KAM08) and 2011 (KAM11) experiments, to measure the time-varying channel response, and to estimate its statistical properties and capacity that play an important role in the design of spectrally efficient communication systems. Besides the capacity analysis for unconstrained inputs, we determine new bounds on the achievable information rate for discrete-time Gaussian channels with inter-symbol interference and independent and uniformly distributed channel input symbols drawn from finite-order modulation alphabets. Specifically, we derived new bounds on the achievable rates for sparse channels with long memory. Furthermore, we explore design aspects of adaptive modulation based on orthogonal frequency division multiplexing (OFDM) for UWA communications, and study its performance using real-time at-sea experiments. Lastly, we investigate a channel estimation (CE) method for improving the spectral efficiency of UWA communications. Specifically, we determine the performance of a selective decision directed (DD) CE method for UWA OFDM-based communications.
Download or read book Bandwidth Optimization of Underwater Acoustic Communications Systems written by and published by . This book was released on 2001 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Current underwater acoustic communication systems operate in the frequency band of 1 - 10 kHz and utilize various forms of signal processing to improve data rates. In this work, the influence of the environment on long-range propagation of acoustic signals will be examined over the band of 1-5 kHz. The transmission loss (Th) as a function of range over the bandwidth will be one measure to determine the optimal operating character of the communications channel. Additionally, estimates of signal variance over the bandwidth as a function of range will be computed. The variance will be generated from source platform motion and interface roughness. Particular attention will be paid to the 2 - 4 kHz band of certain operating systems for long-range transmission.
Download or read book CI OFDM Underwater Acoustic Communication System written by Fang Xu and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: CI/OFDM Underwater Acoustic Communication System.
Download or read book Underwater Acoustic System Analysis written by William S. Burdic and published by Peninsula Publishing. This book was released on 2002 with total page 508 pages. Available in PDF, EPUB and Kindle. Book excerpt: Underwater Aacoustic System Analysis provides a comprehensive exploration of underwater acoustics, acoustic signal generation, and acoustic signal processing for the practicing systems analyst and systems engineer. This second edition, first published in 1991, contains all the valuable information in the earlier edition plus a detailed discussion of of adaptive processing as applied to spatial filtering. Highlights of the book are: * Generation and propagation of compressional acoustic acoustic waves in the ocean * narrowband signatures of surface ships caused by cavitating propeller blades and diesel engine firing * Optimization of signal-to-noise ratio and spatial reslution in the presence of multiple acoustic signals * Ambient noise in the ocean, and * Examples of sytem performance analysis
Download or read book Underwater Acoustic MIMO OFDM written by Guillem Palou Visa and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Underwater Acoustic Networking Techniques written by Roald Otnes and published by Springer Science & Business Media. This book was released on 2012-01-19 with total page 93 pages. Available in PDF, EPUB and Kindle. Book excerpt: This literature study presents an overview of underwater acoustic networking. It provides a background and describes the state of the art of all networking facets that are relevant for underwater applications. This report serves both as an introduction to the subject and as a summary of existing protocols, providing support and inspiration for the development of network architectures.
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 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 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 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 The Use of M Sequences to Optimize Underwater Acoustic Communications in Shallow Waters written by Fabio B. Louza and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The relationship between dynamic ocean acoustic fluctuations and the underwater communication in shallow waters acoustic propagation channels will be investigated, as they present a challenging environment for the transmission of information, causing inter-symbol interference (ISI) and multipath signal spreading and fading. The study and simulations will be based on data from an upwelling monitoring buoy located in the shallow waters of Arraial do Cabo -- Brazil. The focus of this thesis is to perform a systematic analysis of the role of the internal waves and upwelling on phase stability of a signal propagating through the channel, in terms of temporal coherence, using the Monterey-Miami parabolic equation (MMPE) model, and compare two approaches to optimize communication systems: prediction and/or measurement of the channel pulse responses. The first one is based on previous predicted pulse responses, given by MMPE and a matched or inverse filter to retrieve the message through multipath recombination. However, as filtering results begin to erode with time, one can estimate the refresh time of the filters necessary to keep up with real time varying sound speed profiles in these shallow waters. The second approach uses a simultaneous background experiment to directly measure and update the channel pulse response while collecting the message, based on "training pulse response measurements", classic low intensity M-sequences. Finally, the process called Hyperslice Cancellation by Coordinate Zeroing (HCCO) (Chang, 1992) will be performed to eliminate interferences between the M-sequences and the original messages.
