Directly extracting seabed reflection coefficient using ocean ambient noise

A method was proposed for the direct(non iterative) extraction of the seabed reflection coefficient using only two hydrophones arranged vertically.Based on the similarity between the vertical cross correlation function and the directional density function of the ocean ambient noise,and combined with the ray theory of ocean ambient noise,the passive acquisition of seabed reflection coefficient is realized by two vertically arranged hydrophones.Simulation analysis of method adaptability shows that the ocean ambient noise data collected in high sea condition and without near-field ship interference is beneficial to the realization of the method.For two layers seabed,the sediment reflection coefficient of in vertical direction can be accurately extracted from the derivative of the cross correlation function of ocean ambient noise to time after applying high-pass filter to the vertical coherence function of ambient noise.The method is applied to process the measured ocean ambient noise under high wind speed.The results show that the direct extraction method can accurately obtain the seabed reflection coefficient in the part greater than the critical angle.