Reson SeaBat 7125 ROV, Operator'S Manual

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ACTIVE SONAR USAGE
SeaBat 7125 ROV Operator‟s Manual
Page 96 May 30, 2011
Version 3
Figure 40: Acoustic Absorption Reference
6.5.2 Loss of Sound by Spreading
Spreading of sound through water may be the greatest contributor to the loss of sound.
As sound moves away from its source in all directions, the acoustic pressures will
decrease with range.
In deep water, where the acoustic propagation is not bounded by the sea surface or the
seafloor, the spreading loss is spherical. In this case the pressure decrease is
proportional to 1 divided by the range R from the sonar to a given object or surface.