宽带实时三维成像声纳稀疏阵列优化与波束形成方法

Underwater real-time three-dimensional (3D) imaging sonar is a new ocean observation technology. It has wide and urgent application needs in the fields of ocean observation, marine engineering operations, underwater archaeological rescue, harbor guard, frogman detection, mine clearance and explosive disposal, and other civil and military fields. The traditional narrow-band mode has defects in the imaging mechanism, and the wide-band imaging mode has become an inevitable trend. Aiming at the technical difficulties faced by the development of broadband real-time 3d imaging sonar, this project focuses on two major scientific problems, namely, the upper bound of array sparsity and the lower bound of imaging computational complexity, to study the robust sparse array optimization and fast beamforming method. The main research contents include theoretical modeling of broadband sonar echo signal, robust sparse optimization method for large-scale array under manifold mismatch, fast broadband beamforming method with both far-field and near-field imaging performance, underwater target 3D imaging simulation and experimental verification. The research of this project will provide theoretical and technical support for the development of a new generation of real-time three-dimensional imaging sonar based on broadband working mode, and play a positive role in improving the technical level of ocean observation and exploration.

水下实时三维成像声纳是新兴的海洋观测技术，在海洋探测、海洋工程作业、水下考古救援、海港警戒、蛙人探测与扫雷排爆等民用和军事领域均有广泛而迫切的应用需求。传统的窄带工作模式在成像机理上存在缺陷，宽带成像模式已成为技术发展的必然趋势。本项目针对发展宽带实时三维成像声纳所面临的技术困境，聚焦阵列稀疏度上界和成像计算复杂度下界两大科学问题，研究鲁棒性稀疏布阵和快速波束形成方法。主要研究内容包括宽带声纳回波信号理论建模、阵列流形失配下的大规模阵列鲁棒稀疏优化方法、兼顾远场和近场成像性能的快速宽带波束形成方法、水下目标三维成像仿真与实验验证。本项目的研究将为发展基于宽带工作模式的新一代实时三维成像声纳提供理论和技术支撑，对提升我国在海洋观测探测领域的技术水平有积极作用。

本项目面向发展基于宽带工作模式的新型实时三维成像声纳的实际需求，围绕当前宽带成像声纳技术所面临的硬件复杂度高和成像计算量大两项关键问题，开展了大规模稀疏阵列优化与快速宽带波束形成方法研究，提出了基于教与学优化算法和樽海鞘算法的稀疏优化布阵方法，数据结果表明，所提稀疏优化布阵方法可以有效降低系统硬件复杂度。针对宽带成像声纳系统的成像计算量大问题，提出了适用于任意阵形宽带成像声纳系统的快速波束形成方法，利用非均匀快速傅里叶变换（NUFFT）的伴随操作，减少宽带波束形成计算量，提升宽带波束形成计算速度，通过成像仿真和外场试验数据验证了所提出的宽带快速波束形成方法的可行性和有效性。本项目的研究为发展基于宽带工作模式的新一代实时三维成像声纳有积极作用。