Page 432 - The ROV Manual - A User Guide for Remotely Operated Vehicles 2nd edition
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Acoustic Positioning
CHAPTER CONTENTS
16
16.1 Acoustic positioning—a technological development....................................................................425
16.2 What is positioning?..................................................................................................................426
16.3 Theory of positioning.................................................................................................................426
16.4 Basics of acoustic positioning ...................................................................................................427
16.5 Sound propagation, threshold, and multipath .............................................................................. 431
16.5.1 Weaksignals......................................................................................................432 16.5.2 Noise ................................................................................................................ 433 16.5.3 Multipath........................................................................................................... 433
16.6 Typesofpositioningtechnologies..............................................................................................434
16.6.1 Frame of reference ............................................................................................. 434 16.6.2 Short baseline.................................................................................................... 435 16.6.3 Ultrashort baseline ............................................................................................. 436 16.6.4 Long baseline..................................................................................................... 437
16.7 Advantages and disadvantages of positioning system types ......................................................... 441
16.8 Capabilities and limitations of acoustic positioning.....................................................................443
16.9 Operationalconsiderations........................................................................................................445
16.9.1 Operations in open ocean.................................................................................... 445
16.9.2 Operations in ports and harbors ........................................................................... 446
16.9.3 Operations in close proximity to vessels and
underwater structures ......................................................................................... 446
16.10 Position referencing..................................................................................................................447
16.10.1 Geo-referencing of position................................................................................ 447 16.10.2 Vessel referencing of position ............................................................................ 448 16.10.3 Relative referencing of position.......................................................................... 450
16.11 General rules for use of acoustic positioning systems ................................................................. 451
16.1 Acoustic positioning—a technological development
The need for acoustic positioning became apparent with the loss, then difficulty, in locating the atomic attack submarine USS Thresher, which sank in 8400 ft (2560 m) of seawater in 1963, as well as a nuclear bomb lost at sea off the coast of Spain in 1966. The US Navy
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© 2014 Robert D Christ and Robert L Wernli. Published by Elsevier Ltd. All rights reserved.
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