Extraction of mode attenuation coefficient from low frequency reverberation signal

A method of extracting mode attenuation coefficient from low frequency reverberation signal was proposed. Traditional normal mode filtering technique was used to get single mode reverberation field firstly.Based on assumption of separability of bottom model back-scattering matrix,effective back-scattering matrix elements were gotten from single mode average reverberation intensity.Finally,mode attenuation coefficient was extracted by comparing effective backscattering matrix element at different range.The extracted mode attenuation coefficient was used to predict sound propagation field at the same experiment area.The result shows that the predicted transmission loss line agrees well with measured transmission loss line.This method avoided coupling between bottom scattering attenuation and normal mode propagation attenuation.Research on extraction of mode attenuation coefficient from low frequency reverberation signal is useful for both geoacoustic inversion and rapid underwater environment assessment.