A system for and method of determining and compensating for the effect of a field influencing object on a field sensor, preferably a coil, that is within a navigational domain. The navigational domain contains navigational magnetic energy and disturbing magnetic energy, and the field influencing object...http://www.google.com.au/patents/US6493573?utm_source=gb-gplus-sharePatent US6493573 - Method and system for navigating a catheter probe in the presence of field-influencing objects
