|Acoustic inversion with broadband MFP for seabed characterization in OAEX'10 experiment|
Lussac, M.P.; Artusi, L.; Parente R., C.E.; Hermand, J.-P. (2011). Acoustic inversion with broadband MFP for seabed characterization in OAEX'10 experiment, in: Papadakis, J.S. et al. 4th international conference and exhibition on Underwater Acoustic Measurements: Technologies and Results. pp. 8
In: Papadakis, J.S.; Bjørnø, L. (2011). 4th international conference and exhibition on Underwater Acoustic Measurements: Technologies and Results. FORTH/IACM: Kos.
Acoustic inversion, matched field processing, normal modes model, genetic algorithm
|Auteurs|| || Top |
- Lussac, M.P.
- Artusi, L.
- Parente R., C.E.
- Hermand, J.-P.
Acoustic inversion techniques are often used to characterize portions of the marine environment or the seabed. Matched field methods as, e.g., the well known conventional “matched field processing” (MFP) or the “model based matched filter” (MBMF), are able to estimate the best fit from the correlation of modelled acoustic pressure fields with the field measured in an array of hydrophones in the first case, or with the impulsive response in timedomain in the second case. The results of the whole process show estimations of physical parameters that could represent the seabed (attenuations, densities, sound speeds), the water column (sound speed profile, depth) or the geometries (receiver depth, source depth, sourcereceiver range). The technique can be tuned and applied to geoacoustic inversion, acoustic tomography or passive source localization. The present work proposes to present the analysis and results of MFP inversion with broadband data recorded on a 8-hydrophones array during the geoacoustic run of the Ocean Acoustic Exploration 2010 experiment (OAEx'10) nearby Arraial do Cabo city, off the south-east coast of Brazil. The analysed acoustic signals are multi-tones over the frequency band 250 Hz--1000 Hz emitted by a source positioned at 700-m from the receivers, in a environment considered range-independent. Normal modes model, space-coherent Bartlett cost function and genetic algorithm optimization are used to estimate the best replica field and the physical parameters from seabed, producing results in reasonable agreement with previous geophysical ground truth from this brazilian site.