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Some comments on ray theory with examples from current NUC ray trace models
(NATO. SACLANTCEN, 1971/12)
Three topics were covered in this paper: 1. Ray Sweep-out Method - a technique for calculating sound intensities at a large number of receiver points in range and depth . 2. Bi-static Reverberation Model - a technique based ...
Acoustic characterization of a shallow water site
(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 ...
Sound absorption by suspended particulate matter
(NATO. SACLANTCEN, 1997)
A series of experiments has been performed to study the viscous absorption of sound by particulate suspensions typical of those found in coastal waters. The effect due to the particles in the frequency range of 50 - 150 ...
Position and shape of the surface shadow zone
(NATO. SACLANTCEN, 1971/12)
From surface reverberation studies conducted by SACLANTCEN's Target Classification Group"C , it has been found necessary to know before any sea experiment the precise position of the first surface shadow zone. Since normal ...
Signal and reverberation formulae including refraction
(NATO. SACLANTCEN, 2003/04)
Because reverberation is an incoherent process it is possible to base realistic solutions on very simple flux theory. This report extends the closed-form signal and reverberation formulae of an earlier report [SACLANTCEN ...
Ocean-basin reverberation from large underwater explosions: part 1: source-level and propagation-loss modelling
(NATO. SACLANTCEN, 1975/10)
Predicting the reverberant returns from ocean basin reflectors requires describing acoustic source levels for large, conventional underwater explosions, defining the two way propagation loss and signal spreading from the ...
Application of ray tracing with horizontal gradient to monostatic boundary reverberation
(NATO. SACLANTCEN, 1971/12)
Presented is the current work being done at the Naval Research Laboratory (NRL) on the development of a series of computer programs to predict long range, low frequency, monostatic boundary reverberation. The emphasis is ...
Reverberation suppression
(NATO. SACLANTCEN, 1995/05)
We propose a processing methodology for shallow-water reverberation
SUPREMO: a multistatic sonar performance model
(NATO. SACLANTCEN, 2002/11)
Multistatic sonars introduce new problems to the modeller such as mutual interference from multiple sources and variable target aspect in a background of range-dependent bistatic reverberation. A multistatic sonar performance ...
Calculation of reverberation and average intensity of broadband acoustic signals in the ocean by means of the RAIBAC computer model
(NATO. SACLANTCEN, 1976/04)
Based on the conventional ray-tracing principle, a fast numerical algorithm is developed that calculates averaged propagation loss and reverberation of underwater sound. The averaging is performed by summing incoherently ...