Analysis on spatial coherence of ambient noise and geoacoustic inversion in shallow water

The spatial coherence in frequency domain of ambient noise field in shallow water is calculated based oi1 ray theory and simplified seabed model, and it is used to do geoacoustic inversion. The ambient noise is regarded as many point sources in the infinite plan, and the frequency domain expression of the spatial cohernece is obtained by calculating the energy distribution in the vertical direction of the noise field. Then the sensitivity of model to different seabed is verified by numerical simulation. The sound speed, density and attenuation coefficient of tile seabed are further obtained according to experiment data. The result shows that those parameters get from inversion are in good agreement with actual situation. The method in this paper can effectively reflect the influence of seabed reflection on the spatial coherence of noise field, and can improve the inversion efficiency to a certain extent.