A stereoscopic technique for seafloor statistical characterization by acoustic remote sensing

Area of Science:

• Oceanography
• Acoustics
• Geophysics

Background:

• Accurate characterization of underwater surfaces is crucial for marine geology and engineering.
• Existing acoustic methods may have limitations in estimating roughness for surfaces with varying orientations.

Purpose of the Study:

• To develop and validate a novel wideband acoustic remote sensing technique for statistical characterization of underwater surface roughness.
• To enable estimation of surface roughness regardless of the surface's orientation relative to the acoustic instrument.

Main Methods:

• A wideband acoustic signal is used to ensonify the underwater surface.
• Stereoscopic observation from multiple viewing directions captures echoes.
• Comparison of echoes in the frequency domain allows for roughness estimation.
• The scale factor and estimation interval are adjustable by altering viewing angles.

Main Results:

• The proposed method successfully estimates underwater surface roughness height.
• Preliminary experiments in a water tank show agreement between estimated and theoretical roughness values.
• The technique demonstrates flexibility in adjusting the estimation range relative to the acoustic wavelength.

Conclusions:

• The new stereoscopic wideband acoustic method provides a robust approach for underwater surface roughness characterization.
• This technique offers a wide estimation interval, enhancing its applicability in diverse underwater environments.
• The findings support the potential of acoustic remote sensing for detailed seabed and sub-seabed surface analysis.