【作者】 张忠兵；

【导师】 马远良；

【作者基本信息】 西北工业大学 ， 武器系统与运用工程， 2002， 博士

【摘要】 本文主要围绕浅海声速剖面反演方法这一主题开展研究。以获得浅海声速剖面为目的，对浅海声速剖面反演技术进行了探索性研究。采用理论分析、数值仿真方法研究了沉积层参数对浅海多途到达结构的影响；推导和论证了到达时差反演浅海声速剖面算法、提出和研究了用匹配波束处理反演浅海声速剖面算法，并且应用东中国海实验数据对这两种算法进行了验证。主要内容和取得的成果： 1．详细研究了沉积层声速、密度和衰减系数变化对浅海多途到达结构的影响，提出了对多途到达时延差进行分组的研究方法，从理论上对该方法进行了研究。该方法的研究结果验证了一个重要的假设：当信号频率较高时(例如600Hz～1600Hz)，用声线模型计算多途到达时延差与简正波模型得到的结果基本一致，并且声线模型计算多途到达时延差具有较高的可信度。 2．提出了一种基于特征声线的到达时差反演浅海声速剖面的方法，推导和论证了到达时差反演浅海声速剖面的算法。从理论上分析了该算法的收敛性和稳定性，该算法对一定范围内的系统参数失配和沉积层参数失配具有较好的稳定性。应用东中国海实验数据研究了该算法的可行性和实用性，应用该算法反演得到的声速剖面可以达到较高的精度。 3．基于匹配波束处理，提出了用匹配波束处理反演浅海声速剖面(SSP)的思想，研究了匹配波束处理反演浅海声速剖面算法(MDB)。采用东中国海实验数据(爆炸声源数据)研究了该反演算法的可行性。MBI反演SSP对沉积层参数失配具有较高的稳定性，当根据先验信息确定沉积层参数后，MBI反演SSP均方根误差小于匹配场反演方法反演得到的结果，并且MBI反演SSP的温跃层部分更接近实际测量SSP。 本论文提出的基于特征声线的到达时差反演浅海声速剖面和匹配波束处理反演浅海声速剖面两种反演方法均能较快地获得浅海声速剖面，这两种反演方法为快速反演浅海声速剖面的实际应用打下了良好的基础。更多还原

【Abstract】 This dissertation studies the inversion of sound speed profile (SSP) in shallow water,including the effects of sediment parameters on the multi-path arrival structure,the algorithm of the SSP inversion using multi-path arrival time differences and the SSP inversion based on matched beam processing (MBP).1. The effects of sediment parameters on the multi-path structure in shallow water are investigated in detail. A method of dividing the multi-path arrival time differences into groups is presented. Theoretical analysis for the method is given. An assumption is verified that the multi-path arrival time differences calculated by ray model is almost the same as that by normal mode model if higher frequencies for the source are used (e.g.,frequencies range between 600Hz and 1600Hz). hi other words,the calculation of the multi-path arrival time differences by ray model is reliable.2. SSP inversion based on ray arrival time difference in shallow water is presented and related algorithms are developed. The feasibility and practicability of the algorithms are studied by using the experimental data in the East China Sea. The robustness and convergence of the algorithms are theoretically analyzed. The simulation and experimental results show that the algorithms are robust on the mismatch of system parameters and sediment parameters. It is concluded that the proposed approach for SSP inversion is ready for some primitive engineering applications.3. The SSP inversion algorithm based on MBP is investigated. The feasibility of this algorithm is verified by using the experimental data of the East China Sea. The mean error of SSP inversion by this algorithm is less than that by MFI when the sediment parameters is known a priori. The SSP inversion by this algorithm shows a better match to themeasured SSP in the step layer.更多还原