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Showing 1 to 11 of 11 for “"sound speed profiles"”.

  1. A modal/WKB inversion method for determining sound speed profiles in the ocean and ocean bottom

    Casey, Kevin D.Massachusetts Institute of Technology and Woods Hole Oceanographic Institution1988

    Two approaches to determining the ocean sound speed profile using measured acoustic modal eigenvalues are examined. Both methods use measured eigenvalues and mode dependent assumed values of the WKB phase integral as input data and use the WKB phase integral as a starting point for relating the …

    woods-hole Repository record

  2. A modal analysis of acoustic propagation in the changing Arctic environment

    Howe, Thomas (Thomas Ryan)Massachusetts Institute of Technology2015

    … look at acoustic propagation through double duct sound speed profiles in the Arctic. While the traditional Arctic sound speed profile has a single surface duct, some portions of the Arctic have a sound speed profile which includes a second, lower duct. These double duct systems are seen through …

    mit Repository record

  3. Geoacoustic inversion by mode amplitude perturbation

    Poole, Travis L.Massachusetts Institute of Technology and Woods Hole Oceanographic Institution2007

    … modes excited by a low-frequency pure-tone sound source, and estimates of the water column sound speed profiles at the source and receiver positions. The algorithm makes use of perturbation results, and computes the small correction to an estimated background profile that is necessary to …

    woods-hole Repository record

  4. Geoacoustic inversion by mode amplitude perturbation

    Poole, Travis LMassachusetts Institute of Technology2007

    … modes excited by a low-frequency pure-tone sound source, and estimates of the water column sound speed profiles at the source and receiver positions. The algorithm makes use of perturbation results, and computes the small correction to an estimated background profile that is necessary to …

    mit Repository record

  5. Real time bottom reverberation simulation in deep and shallow ocean environments

    Miller, Thomas E.Massachusetts Institute of Technology and Woods Hole Oceanographic Institution2015

    … simulation will include deep and shallow ocean profiles and multiple sound speed profiles (SSP). Following this testing, the goal is to implement the model in existing C++ code used for the testing of AUV systems. The ability to accurately model the ocean will not only allow for testing of …

    woods-hole Repository record

  6. Real time bottom reverberation simulation in deep and shallow ocean environments

    Miller, Thomas Edward, S.M. Massachusetts Institute of TechnologyMassachusetts Institute of Technology2015

    … simulation will include deep and shallow ocean profiles and multiple sound speed profiles (SSP). Following this testing, the goal is to implement the model in existing C++ code used for the testing of AUV systems. The ability to accurately model the ocean will not only allow for testing of …

    mit Repository record

  7. Stochastic acoustic ray tracing with dynamically orthogonal equations

    Humara, Michael JesusMassachusetts Institute of Technology and Woods Hole Oceanographic Institution2020

    … to three idealized cases of stochastic sound-speed profiles (SSPs): constant-gradients, uncertain deep-sound channel, and a varied sonic layer depth. Through this implementation with non-Gaussian examples, we observe the ability to represent the stochastic ray trace field in a reduced …

    woods-hole Repository record

  8. Impacts of short-time scale water column variability on broadband high-frequency acoustic wave propagation

    Eickmeier, JustinUniversity of Delaware2016

    … parabolic equation (PE) model using measured sound speed profiles (SSPs) in the water column. Using the method of beamforming on the received signal, the arrival time and angle of an acoustic beam was obtained for measured acoustic signals. It is determined that the acoustic ray path, acoustic …

    udel Repository record

  9. Forward sound propagation around seamounts : application of acoustic models to the Kermit-Roosevelt and Elvis seamounts

    Kim, Hyun JoeMassachusetts Institute of Technology and Woods Hole Oceanographic Institution2009

    … understanding of the complicated phenomena of sound propagation around the seamounts. In addition, the experimental data could be used to validate current 2D and 3D theoretical models and develop new models to properly realize the sound propagation with such complicated phenomena. In this …

    woods-hole Repository record

  10. Geographic Variations of Sound Channel Axis in the Global Ocean

    Acharya, Mukunda Kumar2020

    Sound signals are used for imaging and communication in the ocean. Underwater sound speed has a minimum at a certain depth that forms a sound channel for long-range underwater sound propagation. The geographic variation of sound channel is crucial in uses of underwater sound in various environments …

    mississippi Repository record

  11. Estimates of crustal transmission losses using MLM array processing

    Scheer, Edward K.Massachusetts Institute of Technology and Woods Hole Oceanographic Institution1982

    … domain. In studying the behaviour of sound in the ocean, the sea floor is often modelled as a boundary with a half space below, and with some form of reflection characteristic and/or loss mechanism. If acoustic energy, upon encountering the bottom, was either reflected or transmitted …

    woods-hole Repository record