基于SQUID梯度计的单磁源定位及磁矩反演误差分析

磁源定位及磁矩反演技术在空间探测、无损检测以及目标追踪等领域有着广泛的应用前景。利用磁场梯度张量信息进行磁源定位及磁矩反演的思想是在1975年首次提出的,2006年提出的磁性目标线性方程定位方法以其快速准确求解的特点而备受关注。但是,对于该梯度张量矩阵求逆法进行磁源定位的全方位的误差分析仍有待完善。在简要回顾梯度张量矩阵求逆法进行磁源定位的方法的基础上,提出了一种基于该方法的系统误差和随机误差分析的理论;研究结果表明定位误差是由于将差分近似为微分而引起的系统误差和传感器测量的随机误差构成。以目前具有超高精度、超高灵敏度的超导量子干涉仪作为典型磁场测量传感器,分析了梯度张量矩阵求逆法进行磁源定位及磁矩反演误差与传感器分辨率和相对误差水平之间的关系。

Error analysis for a SQUID-based magnetic gradiometer magnetic source localization and magnetic moment calculation

The magnetic source location and magnetic moment calculation method shows promising application in space object exploration,non destructive detecting,and target tracking.The primary research focus since 1975 was the magnetic gradient tensor analysis,i.e.based magnetic source location and magnetic moment calculation method.In 2006,a closed form of invert gradient tensor method was presented,which was possible solved by computer quickly and accurately.But there was no systematic error analysis of such method caused by the systematic error owing to the dimensions of the sensor and the statistic error caused by measurements.This paper gave a brief review of invert gradient tensor method and presented a novel theory to do the systematic error analysis and statistics error analysis.The Superconducting Quantum Interference Device(SQUID) was chosen as typical magnetic sensor due to its superior magnetic field sensitivity in system implementation highlighted.As results,the location error as well as the magnetic moment calculation error were presented systemically and statistically as a function of the SQUID's resolution and relative measurement errors.