一种地声参数的联合反演方法

A hybrid scheme for geoacoustic inversion

根据地声参数对不同声场物理量影响不同,提出了一种利用简正波频散特征结合声传播损失反演地声参数的联合反演方法。首先,考虑到简正波的频散特性(群速度)对海底的密度和声速较为敏感,而对海底吸收系数不敏感,利用自适应时频分析方法,获得不同频率不同号数简正波的到达时间差,以此作为代价函数,采用全局优化算法,反演出海底密度和海底声速的分层结构,并用概率统计的方法评价反演结果的有效性。反演出海底密度和声速后,利用实验船辐射噪声得到随距离连续的声传播损失来反演出海底吸收系数。最后,把反演的参数很好的用于声源匹配定位验证了反演结果的有效性。

A hybrid inversion scheme of geoacoustic parameter, which combines dispersion characteristics of normal modes with transmission loss, was proposed based on the facts that different parameters have different effects on sound field. First, considering the dispersion characteristics of normal modes were sensitive to the density and the sound speed of seabottom, and not sensitive to the seabottom attenuation coefficient, then the seabottom density and the profile of seabottom sound speed were inverted by taking the delay of different modes as the cost function. Successively, the validity of inversion was evaluated by the a posteriori probability. Last, the attenuation coefficient of sediment was inverted using the transmission loss data recorded from the ship radiation noise. The validity of the total inversion results has been evaluated by making use of the matched field processing source localization.