#$%^&*AU2012216419B220130815.pdf#####ABSTRACT A method for tracking a position of an object includes using a field sensor associated with the object to measure field strengths of magnetic fields generated by two or more field generators, wherein a measurement of at least one of the field 5 strengths is subject to a distortion. Rotation-invariant location coordinates of the object are calculated responsively to the measured field strengths. Corrected location coordinates of the object are determined by applying to the rotation-invariant location coordinates a coordinate correcting function so as to adjust a relative contribution of each of the measured field strengths to the corrected location 10 coordinates responsively to the distortion in the measured field strengths. N: Graham Clare Speci & Amndmts 20191 Div Specification.Docx, 15/08/121/3 CCO cc
