MarSensing Lda.

Underwater Acoustic Propagation Survey

In coastal regions, an acoustic survey can be conducted with the purpose of characterizing the area or volume as an acoustic propagation channel. This consists in transmitting known acoustic signals to acoustic receivers within the area potentially affected by a future activity. Acoustic transmissions may be performed over a straight line departing from the reference position in order to generate transmission loss (TL) curves, or arbitrary positions relevant for determining the area of impact. As the TL is also a funtion of frequency these transmissions should be performed over a range of frequencies. TL curves may then be used acoustic modeling procedure for matching with modelled TL in order to generate a physical model of the area. This physical model can then be used for predicting sound pressure levels with increased spatial coverage. Acoustic models yield 3D noise maps as a function of range, depth and azimuth. Acoustic modeling is an ecient approach to signicantly increase spatial coverage, not achievable by in situ measurements.