A method and an apparatus for magnetic induction tomography, in which an
object with inhomogeneous passive electrical properties is exposed to an
alternating magnetic field by excitation coils located at different
positions, from which receiver coils located at different positions pick
up AC signals which contain information concerning the electrical
conductivity and its distribution in the object, and images of the
spatial electrical properties in the interior of the object are
reconstructed from the amplitudes and phases of the received signals,
whereas the measurement is carried out at least 2 frequencies and an
additional perturbation of the coils and/or the field geometry so as to
determine a correction factor with which it is possible to widely
eliminate spurious signals generated by changes of the geometry during
the object measurement.