The horizontal acoustic backscattering strength of a fish school is an important factor for fisheries and for estimation of the size of a fish school using omnidirectional scanning sonar. However, the backscattering strength of a fish school is influenced by their behavior and orientation because the individual fish in the fish school have strong directivity of target strength. This paper discu...

underwater target imaging using acoustic waves is possible by employing the method used in synthetic aperture radars. in recent years, synthetic aperture sonar has been the subject of several researches. wherein imaging of underwater moving target is required, inverse synthetic aperture sonar (isas) idea can be used but specifications and limitations of underwater channel should be considered. ...

The most effective method for surveying underwater archeological sites is visually identifying areas with relics or remains through diving surveys. However, during excavations, it difficult to obtain images in turbid water. Furthermore, on-site costly and time-consuming. Marine acoustic geophysical survey equipment not significantly affected by turbidity, excavations often rely on surface inspe...

The problem of synthesizing a direction finding algorithm based on sample composed the output signals limited number channels scanning sonar system is considered. formulated as search for maximum likelihood function by its lattice representation. Options using optimal and quadratic interpolation are errors displacement loss potential accuracy estimated depending dimension, angular step scanning...

The movement parameters of yellow fin tuna schools were analyzed by means of scanning sonar in tuna purse seine capture situations in the Oman Sea in June 2010. There was significant difference in swimming speed and radial swimming direction between the escaped and captured schools. In escaped cases, the fish schools swam faster with mostly horizontal avoidance behavior to the sound stimuli fro...