浅海环境下数据同化声层析方法研究
Study of acoustic tomography based on data assimilation for shallow water environments
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摘要: 讨论了适用于浅海的基于声速局部测量模型、声传播模型及声压场局部测量模型的声学数据同化方法,并给出了具体的执行算法。该算法根据最优化准则把局部声速和声压场的先验测量信息,以及声传播模型进行了有效地融合,提高了海洋环境参数估计的精度,为浅海声层析提供了新思路。同时,利用实验浅海声速测量数据,通过经验正交函数对实际海洋声速剖面进行了估计,并分析了各类噪声对水体声速场及海底声学参数估计精度的影响,验证了该执行算法的有效性。Abstract: Based on the local sound speed measurement model,the acoustic propagation model and the local acoustic pressure measurement model,the approach of ocean acoustic data assimilation suitable to shallow water environments is discussed.In this approach,according to the optimality principle,the a priori knowledge of the local sound speed and acoustic pressure fields is combined with the acoustic propagation model,which effectively improves the precision in the parameter estimation.To validate the approach,the sound speed field in shallow water expressed by empirical orthogonal functions and the geo-acoustic parameters are estimated via a numerical implementation of this approach using the experimental sound velocity measurement data and the effects of different model errors on the prccision in the parameter estimation are analyzed.The approach discussed in the paper gives a novel idea for acoustic tomography in shallow water.