摘要
前向声散射探测中的信直比SDR;能衡量目标前向散射波与直达波的相对大小,但未考虑两种波的干涉叠加。前向散射波与直达波实际上是干涉在一起的且很难分离,因而信直比在目标探测分析中难以直接应用。以信直比为基础并计入前向散射波与直达波的干涉效果,引入了新的参量--干涉声场畸变量ΔFTL--并给出了理论计算公式。与SDR;相比,ΔFTL可以直接从声场数据中得到,在一定程度上具有不依赖先验信息的优势。以该公式为基础并结合千岛湖缩比目标探测试验数据,(1)通过估算几何扩展损失系数发现试验中的声波为球面波,结果与依据实测水文参数的射线声场模型仿真结果相符;(2)定量地证实了ΔFTL与目标穿越位置的对应关系,同时也证明了ΔFTL理论计算公式的有效性;(3)建立了一种新的直达波抑制效果评估方案,并完成了对自适应直达波抑制方法的效能评估。目标透声和航行姿态扰动对试验结果的影响可以忽略。分析结果表明:ΔFTL能够有效代替SDR,为开展前向声散射探测性能分析或直达波抑制效果评估提供理论参考。
The signal to direct-blast ratio SDR;in acoustic forward-scattering detection can measure the relative magnitudes of the forward scattered wave and the direct-blast,but it does not consider the interference between the two waves.These two waves interfere together actually and are difficult to separate,so SDR;is difficult to apply in target detection and analysis directly.Based on the signal to direct-blast ratio and considering the interference effect of the forward scattered wave and the direct-blast,a new parameter called the acoustic interfered field distortionΔFTL is developed,and the corresponding calculation formula is also deduced.Compared with SDR;,ΔFTL can be obtained directly from data,which has the advantage of not relying on prior information to a certain extent.Based on this formula and combined with data from the Qiandao Lake scaled-target detection experiment,(1) the acoustic wave is found to be spherical wave by estimating the geometric expansion loss coefficient,and the results are consistent with the simulation results of ray sound field model based on the measured hydrological parameters,(2) the relation between ΔFTL and the target crossing position is quantitatively confirmed,which proves the effectiveness of the ΔFTL formula,(3) a performance evaluation scheme independent of prior information is established for direct-blast suppression techniques and then applied to the adaptive direct wave suppression method.The influences from acoustic leakage and attitude-angle disturbance of the target on the results can be ignored.These results show that ΔFTL can effectively replace SDR;,providing theoretical references for conducting performance evaluations on the acoustic forward-scattering detection analysis or the direct-blast suppression effect.
作者
何传林
郑轶
马远良
HE Chuanlin;ZHENG Yi;MA Yuanliang(Institute of Oceanographic Instrumeutatiori,Qilu University of Technology(Shandong Academy of Sciences),Qingdao 266100;School of Ocean Technology Sciences,Qilu University of Technology(Shandong Academy of Sciences),Qingdao 266100;School of Marine Science and Technology,Northwestern Poly technical University,Xi'an 710072)
出处
《声学学报》
EI
CAS
CSCD
北大核心
2021年第6期939-949,共11页
Acta Acustica
基金
国家自然科学基金项目(61801275)
山东省自然科学基金项目(ZR2018BF002)资助。
