A quick and effective technique is developed to diagnose the geomagnetic
dipole field based on an unstrained single circular current loop model.
In comparsion with previous studies, this technique is able to separate
and solve the loop parameters successively. With this technique, one can
search the optimum full loop parameters quickly, including the location
of loop center, the loop orientation, the loop radius, and the electric
current carried by the loop, which can roughly indicate the locations,
sizes, orientations of the interior current sources. The technique tests
and applications demonstrate that this technique is effective and
applicable. This technique could be applied widely in the fields of
geomagnetism, planetary magnetism and palaeomagnetism. The further
applications and constrains are discussed and cautioned.