Orthogonal components of electromagnetic field perturbations due to objects characterized by electric or magnetic dipoles are measured along orthogonal axes in a plane. The components are proportional with (3 cos.sup.2 .theta.-1) and (3 cos .theta. sin .theta.), where .theta. is the bearing of the dipole center relative to the device for measuring the field components. .theta. is readily determined from these equations and the range of the object can also be determined from knowledge of the dipole moment.