基于HBT干涉的MEMS传感阵列水下目标被动定位理论与方法研究

Accurate location of underwater target is of great importance for safeguarding national security and maritime interests. As the underwater environment is very complex, and the target signals are affected by many factors, such as noise, reverberation, seabed topography, biological and so on, it is difficult to realize the accurate location of long-distance and low observable target. So, this project introduces the Hanbury Brown-Twiss (HBT) interference theory which has the ultra-sensitivity for optical detection into underwater acoustic field, and a novel passive location method of underwater targets is proposed. Firstly, analyzing the coherence of underwater target signals with HBT interference principle, and gaining the corresponding relationship between target location and the coherence of signals received by sensor units. Secondly, taking the array with better consistency MEMS hydrophone as the measurement tools, revealing the law of location performance of MEMS hydrophone array topology structure based on HBT interference principle, and establishing the measurement model of HBT interference location of underwater target. Finally, integrating research results to build an underwater test system, and optimizing the location model and array topology structure based on HBT interference principle by testing, which can be used to realize accurate location of long-distance and low observable targets. This research will provide novel principle and method for passive location of underwater target in complex environment.

水下目标的精确定位对保障国家安全、维护海域利益至关重要。由于水下环境非常复杂，目标信号易受到噪声、混响、海底地形、生物等因素的影响，难以实现远距离、低可探测性目标的精确定位。为此，本项目将光学测量中具有超灵敏探测特性的HBT干涉原理引入水声场，提出一种新型HBT干涉水下目标被动定位方法。首先，利用HBT干涉测量原理分析水下目标信号的相干性特征，以此为基础得到传感器阵元捕获信号间的相干性与目标位置之间的对应关系。其次，以一致性较好的MEMS水声传感器组成阵列作为测量工具，探究基于HBT干涉原理的MEMS水声传感阵列拓扑结构对定位性能的影响规律，并建立声场HBT干涉水下目标定位的测量模型。最后，集成研究成果，搭建水下测试系统，通过实验优化基于HBT干涉原理的定位理论模型与传感阵列拓扑结构，实现远距离、低可探测性目标的精确定位。本项目的研究为复杂环境下水下目标被动定位提供新的原理和方法。

由于水下环境的特殊性，常规雷达、光学等方法很难进行有效探测，为某些非合作目标的潜入提供了可乘之机，严重威胁我国国家安全。本项目将光学测量中具有超灵敏探测特性的HBT干涉原理引入水声场，提出了HBT干涉水下目标被动定位方法。利用HBT干涉测量原理分析水下目标信号的相干性特征，获取传感器阵元所捕获信号间的相干性与目标位置之间的关系，重点分析了目标自身特性（频谱、声源级、声源个数等）、背景噪声和阵列偏差对传感器所捕获信号相干性的作用机理。建立复杂声环境下基于HBT干涉的传感器阵列对声目标的定位模型，结合声学仿真计算，揭示了传感器阵列拓扑几何参数（阵列及其每个基阵的几何结构、间距及数量）对目标定位性能（作用距离和定位精度）的影响规律，优化传感器阵列拓扑结构。最后，集成HBT干涉定位理论与传感阵列拓扑结构的研究成果，搭建了MEMS水声传感水下测试系统，进行水下目标的定位实验，实验结果表明，定位角度误差小于0.5%，验证了基于HBT干涉的水下目标被动定位方法在真实水环境中应用的可行性，为水下目标被动定位提供了新原理、新方法。