Localization error of magnetic dipole by measuring remote magnetic field and field-gradient tensor

The localization error for a magnetic dipole localized by measuring its remote field and field-gradient tensor and then solving a linear equation, proposed by Nara et al. in 2006, is usually considered independent of the dipole moment posture. Here, analysis of localization error is carried out by computer simulation, it shows that the error is obvious to be highly dependent on the location and direction of the moment by establishing a set of combined coordinates; the localization of an unknown dipole is thus questionable and has to be justified in general. However, in localizing a known dipole as a magnetic marker the error may be small; the optimum sensor–dipole configuration with the smallest localization error is given here.