Searching for objects under the sea bed by the nonlinear acoustics methods

Abstract

Paper presents rules of producing sources of the parametric acoustic waves as an effect of the propagation of two parallel acoustic beams. Wave is generated in the mutual impact area, with a frequency equal to the difference of the frequencies of waves radiated from the original sources. This principle is a base of the construction of parametric sonars with very narrow directional characteristics and relatively low wave frequency. Moreover, the directional characteristics do not have side lobes - a drawback of the classic sonars. Parametric sonars are a good tool of detecting objects on the sea bed and particularly those buried in the sea bed. The use of parametric sonars in searches for objects such as mines or pieces of archeological value is a modern way of carrying out directed exploration of the sea bed.