【作者】 凌青；

【导师】 田坦；

【作者基本信息】 哈尔滨工程大学 ， 水声工程， 2006， 博士

【摘要】 多站址综合检测系统(双、多基地声纳)由于其收发设备分置，因而在水下目标的检测和定位方面，具有很多独特的优点。目前，对于双/多基地声纳的研究，已经引起人们极大的关注。本文依据双/多基地声纳的工作特点，对双/多基地声纳应用中的各种定位方法进行了研究；并通过仿真，对各种方法进行了性能评估和比较。本文的主要研究内容包括以下几个方面：1．从双基地声纳的几何关系出发，列出了双基地声纳方程。对声纳方程中各参数的物理意义及影响因素进行了详细讨论。在对双基地声纳定位原理和定位误差分析的基础上，采用定位精度的几何解释(GDOP)来表示双基地声纳的定位误差。2．针对双基地声纳水下目标定位问题，讨论了二维目标定位的六种基本方法以及优化方法。通过数值仿真，对基本方法中的四种方法的定位性能进行了研究讨论，给出了双基地声纳定位误差的几何分布图。同时，通过对系统各个因素，如系统的各观测量的测量误差、站址误差、基线长度、声速波动等参数对算法性能的影响，得出了各方法定位误差的分布规律；为了充分利用双基地声纳系统的观测数据，提高系统的定位精度，采用加权最小二乘方法对系统的数据进行优化处理，仿真结果表明该方法定位精度明显高于基本方法的定位精度，能有效的改善发射站和接受站侧边区的定位精度，且定位性能受站址测量误差的影响较小。3．讨论了当双基地声纳系统可同时获得三个观测量时，对水下目标进行空间三维定位的四种方法。通过数值仿真，讨论了各方法的定位性能，做出定位误差的几何分布图。通过对系统各个因素算法定位性能的影响，得出了各方法定位误差的分布规律；将仿真结果进行对比，得出结论：距离信息对算法的定位性能影响较小，系统的定位性能主要受角度观测信息的影响较大。实际应用中，努力提高角度测量精度是提高双基地声纳系统定位精度的最有效的办法之一；与二维情况相比，系统实现三维空间目标定位的定位精度略有下降，这是由于引入了高度信息而使系统的误差增大所导致的。4．把双基地声纳系统的定位方法推广到多基地声纳系统的研究中，讨论了多基地声纳系统利用距离信息进行定位的定位原理，并对不同站址布局下，系统的误差分布特点进行了研究，得出最优的站址布局方案。同时，以某型声纳为实例，讨论了多基地声纳的配置方案。5．针对影响声纳性能的混响，对各种类型混响产生的机理进行了分析，研究了混响的相关特性和统计特性，并提出几种混响抑制方法。重点研究了双基地声纳的各种散射模型(海底散射模型、海面散射模型、体积散射模型)，通过对各种影响因素的分析，给出了各种模型的明确表达式，并对模型进行了仿真分析。模型仿真结果表明，影响双基地声纳混响的因素众多，每个因素在对双基地混响的贡献是不一样的，双基地角度的配置和界面性质变化对混响的影响很大，而声速的变化对混响的影响可以忽略不计。本文研究所得出的结论可为双基地声纳进一步的实验研究和双基地声纳的设计提供参考。更多还原

【Abstract】 Because of the separable resource and receiver, multistatic sonar has many special characters in underwater target detection and localization. At present, the research of multistatic sonar has been paid much attention by people. In this thesis, the studies about positioning methods in applying the multistatic sonar are carried out according to the features of this kind of sonars. By simulation, The performances of several methods are compared and evaluated. The main contents of this thesis are summarized as follows:1. The sonar equations of bistatic sonar are developed from an energy point of view. The meaning of the parameter and the effects in sonar equations are studied. Based on analyzing the location principles and errors of multistatic sonar, the localization errors with Geometrical Dilution of Precision(GDOP) are also described in this thesis.2. Aiming at the problem of underwater object location in bistatic sonar, six basic location methods and an optimized method of two-dimensional target are discussed. The performances of four algorithms are evaluated via computer simulations. The geometrical distribution of errors is given. Moreover, the accuracy analysis for different measurements and parameters(such as time measure error, azimuth measure error, buoys error, baseline length and sound velocity fluctuation) are given respectively. To make the best use of the observation datas, the weighted least square localization algorithm is used to improve the accuracy in bistatic sonar. The simulation results show that the positioning accuracy of this algorithm is higher than the other four algorithms, with which the positioning accuracy in stations areas and side areas can be improved effectively. 3. Four algorithms used in positioning three-dimension target are discussed when three measurements can be obtained. The positioning accuracy contours are drawn to evaluate the location performance via computer simulation. The accuracy analysis for different measurements and parameters are given respectively. The simulation results show that the positioning accuracy is influenced by azimuth error greatly. In practice, it can get much better positioning performance to improve azimuth accuracy. Comparing the positioning accuracy in the situation of two-dimension with that in three-dimension, the latter is lower. The reason is that the error of the height is introduced.4. Extending the positioning method in bistatic sonar to the study of multistatic sonar, the algorithm using distance data is discussed. Besides, the geometrical distribution of error in different station layout and the best precept of station position are analyzed.5. The mechanism that produces the three types of reverberation and the correlative characteristics of reverberation are discussed in the thesis. Some methods to restrain reverberation are developed. Three scattering models(bottom scattering, surface scattering and volume scattering model) in bistatic sonars are developed and simulated. The simulation results show that there are many factors to influence the reverberation, each of them has different contribution to the reverberation, and the angles configurations and the characters of interface have main function, and the effect of the change of sound velocity on reverberation can be ignored.The conclusions drawn from the research can provide the reference to further research and devise the bistatic sonar.更多还原