高亚音速飞行目标声学特性分析及跟踪方法研究

The high-subsonic flight targets at a low altitude have the advantages of radar invisibility and good maneuverability, and they are difficult to detect by the radar method. It is a key and difficult technology to be solved urgently in the target early warning and detection, especially in the final ballistic measurement of the test region. The acoustic detection has the advantages of strong anti-interference ability, large operating region and all weather and time work. In this project, the problem of final ballistic measurement in complex electromagnetic environment is identified in the test and identification of weapons. Starting from the acoustic characteristic of high-subsonic targets, the mathematical relationships between target radiation noise and target parameters are established. Considering the effects of the test environment and the target motion, the sound propagation model of high subsonic target is built. Based on the acoustic characteristic model, the relationship between the Doppler characteristic and motion parameters is established, and the motion parameters are estimated by the nonstationary method. Considering the space constraints of the microphone array in the actual flight test, the multi-segment geometric intersection tracking model based on USBL is researched, in which the angle and distance information are respectively estimated by the microphone array and the sound intensity attenuation. The estimated angle and distance information are fused to acquire the target trajectory in the tracking model. The research results of this project are typical applications of low altitude flight target detection, battlefield investigation and final ballistic measurement.

高亚音速低空飞行目标具有隐身性好、机动性强的优势，难以被雷达所探测，是目前目标预警探测尤其是靶场末弹道测量领域亟需突破的关键技术和难点问题。声探测方法具有抗干扰能力强、作用距离较远、可全天候全天时工作等优势。本项目以武器试验鉴定背景下复杂电磁环境的末弹道测量问题为研究背景，从高亚音速飞行目标声学特性入手，建立辐射噪声与目标典型参数的定量关系；考虑试验环境及目标运动的影响，建立高亚音速目标声传播模型；以目标声学模型为基础，建立多普勒特征量与目标运动参数的关系，利用非平稳方法对运动参数进行估计。考虑到实际飞行试验对传感器布设空间的制约，研究基于超短基线阵组的多段几何交汇跟踪模型，利用超短基线阵估计目标角度，利用声强距离模型估计目标距离，在跟踪模型中对位置和角度两类信息进行融合，从而获得目标轨迹。本项目的研究成果可应用于低空飞行目标探测、战场炮位侦查、靶场末弹道测量等典型应用场景中。

本项目以武器试验鉴定背景下复杂电磁环境的末弹道测量问题为研究背景，从高亚音速飞行目标声学特性入手，基于典型高亚音速飞行目标气动噪声的实测数据，考虑到声基阵布设空间的制约，提出了一种基于超短基线阵的高速目标声学跟踪方法。该方法利用各个超短基线阵接收声强极值点分别估计目标运动轨迹垂线方向，计算多个垂线的叉乘向量实现对目标运动方向的估计，建立高亚声速运动目标的分段交汇定位跟踪模型，再利用多面交汇的方式估计得到目标运动轨迹。根据仿真结果，在采用4个传感器基阵时，角度估计平均误差在4°以内，位置估计相对误差在5%左右，验证了该方法的有效性。针对低空高亚音速飞行目标DOA的快速估计问题，以利用布设于有限空间内的声传感器阵实现海面高亚音速目标角度的快速估计为背景，建立了基于均匀线性空间十字阵的宽带时域阵列信号模型，提出了宽带时域多级维纳滤波器的DOA快速估计方法，在降低系统计算复杂度的同时，保持了目标DOA的高分辨率估计。通过改进基于小波函数的波达方向估计算法，并采用时频分析方法进行特征分析，获取气动噪声显著目标特性。通过优化时间-空间谱特征，对在时频域空间谱的目标信号进行优化，从而增强目标信号在空间谱上的显著性，最终有效实现亚音速飞行弹道气动声源的角度估计。本项目的研究成果可应用于低空飞行目标探测等典型应用场景中。