Method and apparatus for locating a magnetic object using the perturbation of the earth's magnetic field

A method is provided for tracking a magnetic object situated in an area in which a system of coordinates is defined, including an axis of abscissas, an axis ordinate and a height axis. The method includes: a phase of measuring at least one magnetic parameter in multiple measuring points in the area, in order to obtain multiple values take from this parameter in the measurement method including the following steps: construction of at least on projective magnitude; and establishment of the at least one projective magnitude on the values extracting in order to obtain an estimated value of a parameter proportional to a sensitivity within the multiple estimated points of the area, allowing the tracking of the object to take place.