Multipole characterization of a magnetic source using a truncated SVD

This paper presents a new technique for characterizing a magnetic source using truncated singular value decomposition (TSVD). It shows how the smallest singular value of the matrix of signature magnetic fields relates to the sensitivity of the restored multipoles to noises. The crosstalk and altercation due to the truncation of singular values are introduced as the parameters to determine an acceptable truncation limit. Numerical simulations with standard sources are tested using a rectangular array of magnetic field sensors. The results show that TSVD can greatly improve the accuracy of the field restoration.