便携式瞬变电磁系统未爆弹特征化准确性研究

Research on Accuracy of Unexploded Ordnance Characterization of Portable Transient Electromagnetic System

为解决未爆弹尺寸、深度和倾角对其特征化准确性的影响问题,基于便携式瞬变电磁系统,利用偶极子模型与差分进化算法,以标定的未爆弹电磁特性为参考设计对比实验。实验结果表明,对倾角为0°的目标,特征响应更多集中在目标头部,结果比标定值小;而倾角为90°时,特征响应是目标各部分特征响应的总和。由于各部分与系统距离不同,导致反演特征响应大于标定值,因此特征响应随着倾角增大而增大;深度越大,偶极子模型的适用度越高,特征响应越接近标定值,不同倾角下的反演结果一致性越好;目标尺寸越大,特征响应幅度就越大,但目标受倾角变化的影响越大,而小尺寸目标各个角度特征响应的一致性更好,与标定结果更吻合。综上,尺寸、深度和倾角等因素导致特征响应的结果有误差,但总体不影响基于偶极子模型对目标进行分类。

Based on a portable transient electromagnetic system, we use a dipole model with a differential evolutionary algorithm to investigate the effects of target size, depth and inclination angle on the accuracy of its characterization, using the electromagnetic characteristics of a calibrated unexploded bomb as a reference. The experimental results show that for a target with an inclination angle of 0°, the characteristic response is more concentrated in the head of the target and the result is smaller than the calibration value, when for an inclination angle of 90°, the characteristic response is the sum of the characteristic responses of all parts of the target, so the characteristic response increases with the increase of the inclination angle. The larger the depth, the higher the applicability of the dipole model, and the closer the characteristic response is to the calibration value. The larger the depth, the higher the applicability of the dipole model, the closer the characteristic response to the calibration value, and the better the consistency of the inversion results under different inclination angles. The larger the size of the target, the more the target is affected by the change of inclination angle, the better the consistency of the characteristic response from all angles of the small-size target, and the better it matches the calibration results. In summary, factors such as size, depth and inclination angle lead to errors in the results of the feature response, but in general do not affect the classification of targets based on the dipole model.