基于虚分量电磁法的微金属含量地雷探测方法研究

The research on the method of landmine detection has the vital significance to safeguard the national security, protect people's life in the minefield of border, guarantee the development of local economic. For the detectivity of total field electromagnetic method for the landmine with trace amount of metal is weak，this project intends to carry out the research on the detection of the landmine with trace amount of metal based on the quadrature electromagnetic method, which on the basis of applicant’s PhD thesis and the project team’s research on landmine detection based on electromagnetic method at the early stage. The main research includes: the physical model and electromagnetic response characteristics of the typical magnetic and electrical background soil is studied，which is to analyze the mechanism that how electrical conductivity and magnetic permeability of the background soil interference the detection of the landmine with trace amount of metal; based on the quadrature electromagnetic method, the method that how to extract the anomaly field of the landmine with trace amount of metal is studied to improve the anti-interference ability of the instrument in the background soil with strong electrical conductivity and magnetic permeability, therefore the pure target signal will be extracted; the anti-interference design and self-adaption learning method of the electromagnetic induction sensor are studied, so as to improve the ability of anti-interference and self-adaption of instruments in the different environment. A test platform is planted to build up to verify this theoretical method and test the sensor, and a new prototype of detector for landmine with trace amount of metal is developed. This study will provide a detection method of landmine with trace amount of metal, which could make the instruments have stronger anti-interference ability under complicated background, and it also will promote the development of method and technology of landmine detection, which has important scientific significance and application value.

地雷探测方法研究对保障国防安全、边境雷区人民生命安全及经济发展具有重要意义。在申请人博士论文和课题组前期对电磁法探雷研究的基础上，针对总场电磁法在强导电导磁土壤背景下对微金属含量地雷探测能力较差的问题，本项目拟开展基于虚分量电磁法的微金属含量地雷探测方法的研究。主要内容有：建立典型磁性和电性背景土壤的物理模型并研究其电磁响应特征，以分析背景土壤导电性和导磁性干扰微金属含量地雷探测的机理；研究基于虚分量电磁法的微金属含量地雷异常场提取方法，以提高仪器在强导电导磁土壤上的背景干扰抑制能力从而提取出纯目标信号；研究电磁感应传感器抗干扰设计及环境自适应学习方法，以提高仪器在不同环境中的抗干扰和自适应能力。拟搭建实验平台来验证理论方法并测试传感器，进而研制新型微金属含量地雷探测器样机。本研究将为复杂背景下微金属含量地雷探测提供抗干扰能力更强的方法，促进探雷技术的发展，具有重要的科学意义和应用价值。

地雷探测方法研究对保障国防和人民生命安全具有重要意义。当利用传统总场法，在导磁的矿化土壤上进行反步兵塑料地雷探测时，土壤的背景场干扰成为了制约地雷探测性能提升的主要因素之一。. 针对上述问题，本项目开展了基于虚分量电磁法的微金属含量地雷探测方法的研究。主要工作有：（1）建立了基于圆柱坐标系的半空间均匀介质模型，以对土壤背景场的特征进行定量分析。理论仿真结果表明，在导磁土壤产生的背景场中，实分量占主导，而虚分量对电性参数、传感器高度等因素的变化不敏感。（2）利用圆球近似模型，建立了地雷铁磁性部件的电磁响应模型，并对其二次场的虚分量进行了定量分析。理论仿真结果表明，虚分量法可以提取出目标二次场信号，并确定了其最佳激励频率。在虚分量法的基础上，本项目进一步提出了双频激励法实现了在强矿化土壤上的纯目标二次场信号的提取。（3）为提高传感器的抗干扰能力，本项目设计了一种基于 “双D形”差分式接收结构的电磁传感器；针对因外界环境和土壤背景变化所导致的电磁感应传感器传递函数变化问题，本项目提出了一种基于预学习方式的传感器校正方法，来提高环境自适应能力，从而进一步提高了探测距离。针对弹片等其他杂质造成的电磁传感器虚警率偏高的问题，本项目还研制了基于小型Overhauser磁梯度传感器，用于对铁磁性杂质进行辅助识别。（4）搭建一个包含电磁传感器、Overhauser地磁总场传感器、三维扫描导轨的实验平台，用于传感器测试。. 在空气中的实验结果表明，仪器对反步兵塑料地雷的极限探测距离达到了19cm；在无锡近地面探测与感知技术重点实验室开展的实地探测实验结果为：15cm（粘土）、15cm（红土）、14cm（磁土）。基于上述成果，本项目发表SCI论文3篇，申报发明专利2项，获得仪器仪表学报年度优秀论文奖等科研奖励2项。. 本项目初步解决现有常规总场类探雷传感器无法在磁土上进行正常探测的问题，对提高传感器的环境适应性具有推动意义，未来还将继续推动仪器的规模化应用。