针对水下探测设备的方位分辨力在物理上受限于阵列有效孔径的约束，导致探测精度较低的问题，提出一种基于时空特征融合的水下目标波束形成算法。首先，以目标声散射回波产生机理为基础，建立走航声呐回波数据动态数学模型；其次，通过对目标声散射回波数据的时空域转换得到等效空间阵列，融合空域多快拍数据实现阵元基阵孔径的物理扩展。最后，分析干扰信混比、探测平台移动速度等对回波增强的影响。数据仿真结果表明所提方法能够有效抑制干扰，获得主瓣更窄的波束。孔径扩展后的波束形成能够准确地分辨出非常相近的目标。此外，实验结果测得探测平台运动速度大小对目标分辨的效果影响不明显。
In order to solve the problems that the azimuth resolution of underwater detection equipment is physically limited by the effective aperture of the array, the detection accuracy is low, and present an research on underwater target beamforming method based on time and spatial domain feature fusion. Firstly, based on the mechanism of target acoustic scattering echo, a dynamic mathematical model of sonar echo data is established. Secondly, the equivalent spatial array is obtained by transforming the target acoustic scattering echo data in time and space domain, and the physical expansion of the array aperture is realized by fusing the spatial multi-snapshot data. Finally, the effects of jamming-to-signal ratio and moving speed of detection platform on echo enhancement are analyzed. The data simulation results show that: the proposed method can effectively suppress interference and obtain a beam with narrower main lobe. Beamforming after aperture expansion can accurately distinguish very close targets. In addition, the experimental results show that the velocity of the detection platform has no obvious influence on the target resolution.
2022,44(11): 140-145 收稿日期：2021-07-23
DOI：10.3404/j.issn.1672-7649.2022.11.029
分类号：TB566
基金项目：国家自然科学基金资助项目（61901079）
作者简介：丁元明(1967-)，男，教授，研究方向为水下信号处理
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