【作者】 蒋伟；

【导师】 马远良；

【作者基本信息】 西北工业大学 ， 水声工程， 2007， 硕士

【摘要】 本论文研究分析了小尺度传感器阵列超指向性形成的原理和实现方法。参考现有方法，并基于实际科研课题，将传感器阵列超指向性形成方法分为三类数学模型：最大信噪比超指向性数学模型、方向性综合超指向性数学模型和谐波模态重构超指向性数学模型。对该三类模型进行了细致的原理分析和数学推导证明。并且引入了声场计算的边界元方法，使得三类模型具有广泛的适用性。论文的工作主要包括以下几个方面： 1．指出了阵列超指向性研究的重要意义和应用价值，介绍了阵列超指向性概念。 2．细致分析了最大信噪比超指向性数学模型，推导出阵列获得最佳超指向性时阵元权值计算的一般公式。对直线阵和圆环阵的超指向性形成进行了重点分析，推导出圆环阵超指向性形成时最佳权向量的解析公式，以及波束计算公式。 3．推导分析了任意结构圆环阵傅立叶级数展开方向性综合数学模型，给出了方向性合成的阵元加权公式、超指向性指数以及波束计算公式。引入了声场计算的边界元法，使得模型能适合任意障板结构的圆环阵。制作了多种结构圆环水听器，进行了水池实验。 4．推导分析了基于平面波声场模态重构的超指向性数学模型，提出了诸如球谐波模态分解器、入射声场傅立叶分解器等概念，介绍了其优化设计方法。给出了球谐波模态重构超指向性、傅立叶模态重构超指向性的数学证明以及权值计算的解析公式。针对圆环阵，进行了实验验证。 5．建立了一种复杂结构水听器基阵阵列流形计算模型。该模型运用声场计算的边界元方法，求出基阵阵元位置处声场响应，进而得到基阵阵列流形。进行了水池实验，实验结果证明该模型的正确性和准确性。更多还原

【Abstract】 This dissertation studies and analyses the principles and realization of the super-directivity beamforming for the small-scale sensor array. Based on the various existing methods or approaches, the dissertation divides the super-directivity beamforming research into three mathematical models: the super-directivity beamforming model based on maximum signal-to-noise principle, the super-directivity beamforming model based on pattern synthesis and the super-directivity beamforming model based on field reconstruction via mode components. The dissertation especially and carefully concentrates on the analysis and mathematical induction of these three models. Moreover, the proposed three models are more practical because of the introduction of the sound field modeling via boundary element method. The main contributions of this dissertation are presented as follows:1. The importance and intention of the super-directivity beamforming are presented, and the conception of the super-directivity is presented in this dissertation.2. The super-directivity forming model based on maximum signal-to-noise principle is carefully analyzed. The general weighting formula for the array elements to obtain maximum directivity index is also presented. The analysis of the super-directivity beamforming is carried out for linear array as well as circular array. Furthermore, the analytical formula for circular array weighting and beam pattern calculation are given.3. Much attention is paid on the super-directivity beamforming model based on pattern synthesis. The array weighting formula for beam pattern synthesis and the formulae for super-directivity together with the beam pattern calculation are also presented. Due to the use of the boundary element method, the model becomes more practical for the circular arrays mounted on arbitrary baffles. Water-tank experiments are carried out for several circular arrays mounted on baffles of different forms.4. The super-directivity beamforming model based on field reconstruction via mode components is also studied. The concepts of spherical harmonic mode decomposer, the Fourier decomposer for the incoming sound field etc. are presented. The optimum design procedures are also presented in the dissertation. Besides, the mathematical analysis for the super-directivity forming via the reconstruction of spherical mode and Fourier mode is also explained. Data更多还原