Quantitative Analysis of the Measurable Areas of Differential Magnetic Gradient Tensor Systems for Unexploded Ordnance Detection

Achieving effective detection of unexploded ordnance (UXO) is of great significance for ensuring the safety of human lives and regional economic development. Differential magnetic tensor gradient systems have strong application prospects for UXO detection because of their low orientation requirements and exceptional sensitivity to weak magnetic fields. These systems usually have a hollow ring-shaped measurable range, referred to as the “measurable area”. With the rapid advancement of the tensor measurement system, it is necessary to further analyse the measurable area performance. In this paper, a simulation method based on a target magnetic dipole revolving around such a measurement system is designed for evaluating the measurable area. An improved Frobenius norm is adopted to compare the measured tensor data, and the centre distance is used instead of the baseline distance to better describe the scale of the measurement system. The measurable areas of planar cross-shaped, square, and triangular structures are studied, as well as the corresponding influencing factors. Finally, the quantitative relationships between the measurable area performance of the three structures and the magnetic dipole moment direction, the sensor accuracy, and the centre distance of the measurement system are obtained.