基于连续震源的煤层反射式槽波精细探测理论研究

In the preliminary research，it is found that applying multiple correlation receiving filter to separate the underground coal mine multipath signals could greatly enhance the accuracy of underground detection. Meanwhile, it is urgent to carry out the research of fine underground detection. Based on our earlier achievements, the slot wave is used to carry out the precise underground detection, which will mainly solve the problems of poor detection property, multifarious equipments and weak operability etc. The study is firstly focused on the propagation characteristics of slot wave, the filter method of in-band interference and the fine structure modeling. Secondly, the propagation characteristics of slot wave are expected to be found by analyzing the propagation speed, model, dispersion, frequency transfer and multipath, etc. Furthermore, the characteristics of the small underground geological structure slot wave field are expected to be found by getting the travel time sequence with the help of RAKE filter group. Expectedly, a more convenient and accurate small underground geological structure modeling method can be found to be used in the underground environment.The project is expected to establish a solid theoretical and technical foundation for the underground coal mine detection and improve the theoretical system concerning about the existing small coal mine geological structure detection, productive aquifer identification and rich gas structure identification of underground detection. What's more, the research will supply the technical and theoretical preparation for the research of strata slot wave radar. Meanwhile,the research will also play an important role in mine production, disaster relief, geological exploration, military surveillance etc.

开展煤矿井下精细探测方法的研究迫在眉睫；在前期的预研过程中发现,利用相关接收滤波器分离煤矿井下弹性波的多径信号，有可能大幅度提高井下探测的精度。我们拟在原有成果基础上，针对目前煤矿探测中精度低、设备繁杂和操作性差等问题，基于连续震源,采用传播距离较远的槽波来进行井下精细探测。通过研究槽波传播特性、带内强干扰滤除方法、精细构造建模等问题，通过分析槽波传播的速度、模式、频散、频率迁移和多径等参数，弄清煤矿槽波传播规律，找到利用RAKE相关滤波器组分析得到的精确走时序列来描述典型地质构造槽波波场特征的方法，从而找到一种适用于井下环境、使用方便且精准度高的井下小地质构造的建模方法。预计项目的开展将为矿井井下精细探测打下理论和技术基础，完善现有煤矿小地质构造探测、富水层识别和富瓦斯结构识别等井下探测相关的理论体系，为地层槽波雷达的研制做技术与理论准备，从而为矿山救灾减灾、地质探测、军事侦察等服务。

为了解决地层精细探测问题,项目组以煤矿井下地层为应用目标,进行了槽波传播特性研究,并在分析现场采集数据的基础上,提出了利用非正交方法进行槽波波场分离的方法,并在现场进行了相关试验模型的验证工作。并基于槽波的传播特性，借鉴拟合孔径雷达和相控阵雷达的原理，提出了相控发射逆合成接收探测方法，在原理上，将槽波探测精度提高到了厘米级或更高。基于地层信道恒参特点，在经典对消器原理的基础上，结合波场分离研究成果，提出了利用预接收数据进行强回波对消的对消器，滤除带内强干扰滤波，理论上能将接收灵敏度提高80dB以上，实际测试，接收灵敏度提高了46.5dB。 . 项目组对常见小地质构造中槽波传播特性进行分析，发现在地层渐变介质分布界面产生的回波中有类似多普勒信号的信号分量，通过分析这些分量的特征，可以反演地层介质分布情况，并基于上述发现提出了渐进介质界面探测方法。. 项目达到了预期研究目标，借助现代信号处理方法，提出了从震源弹性波发射方法到回波高灵敏度接收方法的系列理论与技术，为槽波地质雷达的研制打下了理论基础。