Browsing CMRE Publications by Title

Now showing items 75-94 of 882

    • Abstracts from the Decision Support and Risk Assessment for Operational Effectiveness (DeSRA) 2016 conference 

      Vicen Bueno, Raul; Coelho, Emanuel; Bourque, François-Alex (CMRE, 2016/08)

    • Accuracy of synthetic aperture sonar micronavigation using a displaced phase centre antenna 

      Pinto, Marc A.; Fioravanti, Stefano; Bovio, Edoardo (NATO. SACLANTCEN, 1999/02)
      This work evaluates the accuracy of multi-element synthetic aperture sonar (SAS) micronavigation based on the concept of displaced phase centre antenna (DPCA). The Cramér-Rao lower bound (CRLB) for the joint estimation of ...

    • Achievable signal gains for line arrays in shallow water 

      Hanrahan, J. J. (NATO. SACLANTCEN, 1993/08)
      The well-documented conformance of signal gain to a 20 log n relationship for deep water, refracted paths, does not apply to shallow water where angular spreading effects from boundary roughness limit the signal gains that ...

    • Acoustic ambient noise in the Barents Sea 

      Grenness, Øivind (NATO. SACLANTCEN, 1982/06)
      Recorded observations of acoustic ambient noise in the Western Barents Sea are presented. The observations were made in a position approximately 100 km North of North Cape in Norway, with the hydrophone on the bottom - ...

    • Acoustic bottom characterization of a shallow water area west of Mallorca 

      Caiti, Andrea; Ingenito, Frank; Kristensen, Age; Max, Michael D. (NATO. SACLANTCEN, 1995/12)
      An experiment was conducted in shallow water on the Balearic Shelf

    • Acoustic bottom reflectivity 

      Hastrup, Ole F. (NATO. SACLANTCEN, 1989/06)
      Acoustic reflectivity from the seafloor is often an important factor influencing the performance of ASW systems in different environments, such as in deep water when the bottom bounce paths are used, and in general in ...

    • Acoustic characterization of a shallow water site 

      Cable, P.; Marshall, W.; Kooij, Theo; Skarda, G.; Waldman, K. (NATO. SACLANTCEN, 1993/08)
      Results are presented from an exercise aimed at providing a low frequency active sonar environmental characterization of a specific shallow water site in the Gulf of Mexico. Downward refracting acoustic transmission and ...

    • Acoustic characterization of submerged aquatic vegetation 

      McCarthy, Elena (NATO. SACLANTCEN, 1997)
      The acoustic characteristics of submerged aquatic vegetation (SAV) were investigated in order to enhance the performance of mine-hunting and weapon sonars in littoral reglons. The specres of seagrass initially studied was ...

    • Acoustic effects of internal microstructure 

      Mintzer, David (NATO. SACLANTCEN, 1975/10)

    • Acoustic impact of upper ocean models 

      Porter, M. B.; Piacsek, Steve; Henderson, Laurel; Jensen, Finn B. (NATO. SACLANTCEN, 1989/12)
      The upper mixed-surface layer of the ocean, with its homogeneous vertical temperature profile, provides a somewhat special acoustic propagation environment where the sound speed will increase (due to pressure) down to the ...

    • Acoustic models at SACLANTCEN 

      Schneider, Hans G. (NATO. SACLANTCEN, 1995/03)
      The Environmental Modelling Group at SACLANTCEN maintains a suite of computer codes to model sound propagation in the ocean. This suite contains numerical models to cover all environmental conditions and acoustic frequencies ...

    • Acoustic noise models 

      Cox, Henry (NATO. SACLANTCEN, 1975/10)
      The question of modeling the vertical directionality of ambient noise in the ocean is considered. The problem of converting from a description in terms of directional density function to a description in terms of the ...

    • Acoustic propagation models as viewed by the sonar systems designer 

      Reeves, J. L. (NATO. SACLANTCEN, 1971/12)
      The purpose of this paper is to consider the efforts performed in the development of ray acoustic propagation analyses from the viewpoint of advanced sonar system design. In particular, those parameters required of such ...

    • Acoustic propagation through oceanic fronts 

      Daintith, Maurice J. (NATO. SACLANTCEN, 1971/12)
      A resume was given of recent experiments in the Mediterranean, East of Malta, designed as a preliminary test of the effect of oceanic fronts on acoustic propagation. It was apparent that in certain circumstances the ...

    • Acoustic properties of the sea floor: a review 

      Hamilton, Edwin L. (NATO. SACLANTCEN, 1975/10)

    • Acoustic scattering from rough surfaces 

      Hurdle, B.; Flowers, K. D.; DeSanto, John Anthony (NATO. SACLANTCEN, 1975/10)
      A review of scattering from the ocean bottom and ocean ice cover is given. Areas of deficiency are cited.

    • Acoustic scintillations of acoustic waves 

      Munk, B. (NATO. SACLANTCEN, 1975/10)

    • Acoustic signal dispersion and distortion by shallow undersea transmission channels 

      Rice, Joseph A. (NATO. SACLANTCEN, 1997)
      The undersea littoral is an adverse medium for acoustic signal transmission to horizontal ranges of many water depths. Reflections and scattering in the bounded, nonhomogeneous channel disperse the arrivaj of received ...

    • Acoustic source characteristics of merchant ships 

      Heine, John C. (NATO. SACLANTCEN, 1982/06)
      Merchant ships are sources of broadband acoustic noise which can interfere with and confuse ocean surveillance. The purpose of this discussion is to review: the status of research on and measurements of merchant ship ...

    • Acoustic source-level measurements for a variety of merchant ships 

      Scrimger, Paul; Heitmeyer, Richard M. (NATO. SACLANTCEN, 1988/07)
      This report describes a set of 50 source spectra obtained from merchant ships of opportunity near Genova, Italy. These spectra were obtained from radiated-noise spectra measured on a towed array and a transmission-loss ...