Low-frequency Ambient Noise in the Deep Sound Channel PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Low-frequency Ambient Noise in the Deep Sound Channel PDF full book. Access full book title Low-frequency Ambient Noise in the Deep Sound Channel by Ronald A. Wagstaff. Download full books in PDF and EPUB format.
Author: Ronald A. Wagstaff
Publisher:
ISBN:
Category : Noise
Languages : en
Pages : 10
Get Book Here
Book Description
Author: Ronald A. Wagstaff
Publisher:
ISBN:
Category : Noise
Languages : en
Pages : 10
Get Book Here
Book Description
Author: Robert J. Urick
Publisher:
ISBN:
Category : Ambient sounds
Languages : en
Pages : 212
Get Book Here
Book Description
Author: Stephen Nichols
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
In the ocean sound channel, where sounds are known to propagate great distances, the ambient noise field is a dynamic mixture of many distinct noise sources. This work is focused on identifying predictable properties of the low frequency (
Author: Robert J. Urick
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 216
Get Book Here
Book Description
Ambient noise may be loosely said to be unwanted sound emanating from the sea itself. Its constituents typically come from a variety of somewhat diffusely combined sources: pressure changes and hydrostatic effects of tides and waves, oceanic turbulence, seismic disturbances, distant ship traffic, wind, rainfall, collapse of bubbles created by wave action, thermal agitation, marine animals and biological activity, breaking ice, and man-made noise such as distant oil rigs. Depending on locations in the ocean space, the times of day, season and year, and the happenstance of events and nature, the aforecited sources may or may not be contribute to the totality of ambient noise at any given time and place; and it may or may not exist as broad or narrow bands of energy in different regions of the frequency spectrum. More exactly defined, ambient noise is that part of the total noise background observed by an omnidirectional hydrophone in the sea which is: (1) not due to the hydrophone system's self-noise such as the noise of current flow around the measurement hydrophone and all forms of electrical noise; ambient noise is independent of the means used to observe it; and (2) not due to other identifiable localized sources of noise. Ambient noise is what is "left over" after all identifiable noise sources are accounted for. Ambient noise is an especially important consideration in detecting and identifying targets - be the targets submarines, underwater vehicles, floating mines, or fish-- in relatively quiet ocean environments and situations. In the case of active sonar, ambient noise typically becomes the dominant background against which the sonar receiver is trying to detect, and possibly identify, targets in the ocean space (not addressing search of the ocean floor) when it is greater than self noise and after the relatively loud reverberation noise created by the active sonar pings has died down in the sonar cycle. In the case of passive sonar, after taking into account self noise and possible extraneous noise from identifiable sources, ambient noise is the background against which the sonar receiver seeks to detect and identify targets. This book, AMBIENT NOISE IN THE SEA by Robert Urick, summarizes the main features of the ambient noise and gives the reader an easy to read, understandable entry in to its unclassified literature. This book is a must for engineers in the fields of active and passive sonars, underwater sensor and weapons systems, and underwater signal processing.
Author: Y. T. Chan
Publisher: Springer Science & Business Media
ISBN: 9400922892
Category : Science
Languages : en
Pages : 642
Get Book Here
Book Description
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.
Author: B.R. Kerman
Publisher: Springer Science & Business Media
ISBN: 9789027727619
Category : Science
Languages : en
Pages : 662
Get Book Here
Book Description
In its relentless pursuit of further knowledge, science tends to compartmentalize. Over the years the pursuit of What might be called geophysical acoustics of the sea-surface has languished. This has occured even through there are well-developed and active research programs in underwater acoustics, ocean hydrodynamics, cloud and precipitation physics, and ice mechanics - to name a few - as well as a history of engineering expertise built on these scientific fields. It remained to create a convergence, a dialogue across disciplines, of mutual benefit. The central theme of the Lerici workshop, perhaps overly simplified, was 'What are the mechanisms causing ambient noise at the upper surface of the ocean?' What could hydrodynamicists contribute to a better understanding of breaking wave dynamics, bubble production, ocean wave dynamics, or near-surface turbulence for the benefit of the underwater acoustics community? What further insights could fluid dynamicists gain by including acoustic measurements in their repertoire of instrumentation? While every attendee will have his or her percep tions of details, it was universally agreed that a valuable step had been taken to bring together two mature disciplines and that significant co-operative studies would undoubtedly follow. The scope of the workshop was enlarged beyond its original intent to also include the question of ice-noise generation. The success of this decision can be seen in high quality of the presentations. the contribution of its disciples in the other workshop discussions and the heightened awareness and interest of we other novices.
Author:
Publisher:
ISBN:
Category : Noise
Languages : en
Pages : 364
Get Book Here
Book Description
Author: B.R. Kerman
Publisher: Springer Science & Business Media
ISBN: 9400930178
Category : Science
Languages : en
Pages : 629
Get Book Here
Book Description
In its relentless pursuit of further knowledge, science tends to compartmentalize. Over the years the pursuit of What might be called geophysical acoustics of the sea-surface has languished. This has occured even through there are well-developed and active research programs in underwater acoustics, ocean hydrodynamics, cloud and precipitation physics, and ice mechanics - to name a few - as well as a history of engineering expertise built on these scientific fields. It remained to create a convergence, a dialogue across disciplines, of mutual benefit. The central theme of the Lerici workshop, perhaps overly simplified, was 'What are the mechanisms causing ambient noise at the upper surface of the ocean?' What could hydrodynamicists contribute to a better understanding of breaking wave dynamics, bubble production, ocean wave dynamics, or near-surface turbulence for the benefit of the underwater acoustics community? What further insights could fluid dynamicists gain by including acoustic measurements in their repertoire of instrumentation? While every attendee will have his or her percep tions of details, it was universally agreed that a valuable step had been taken to bring together two mature disciplines and that significant co-operative studies would undoubtedly follow. The scope of the workshop was enlarged beyond its original intent to also include the question of ice-noise generation. The success of this decision can be seen in high quality of the presentations. the contribution of its disciples in the other workshop discussions and the heightened awareness and interest of we other novices.
Author: William M. Carey
Publisher: Springer Science & Business Media
ISBN: 1441978321
Category : Science
Languages : en
Pages : 266
Get Book Here
Book Description
This monograph develops the theory of noise mechanisms and measurements, and describes general noise characteristics and computational methods. The vast ambient noise literature is concisely summarized using theory combined with key representative results. The air sea boundary interaction zone is described in terms of nondimensional variables requisite for future experiments. Noise field coherency, rare directional measurements, and unique basin scale computations and methods are presented. The use of satellite measurements in these basin scale models is demonstrated. A series of appendices provides in-depth mathematical treatments which will be of interest to graduate students and active researchers.
Author: Robert J. Urick
Publisher:
ISBN:
Category : Noise
Languages : en
Pages : 208
Get Book Here
Book Description
