Patent ID: 7747307

Claim:
A method in a computing system for locating a dipole source of a magnetic field, the dipole source being a marker implanted in or affixed to an organism, the method comprising: receiving a set of actual measurements, each actual measurement indicative of a component of the magnetic field at each of a plurality of sensors; providing sets of reference measurements, each set of reference measurements being associated with a location such that an actual measurement from that location is expected to be a linear combination of that set; providing a set of augmented measurements, such that interference at the sensors is expected to be a linear combination of that set; selecting the location associated with the set of reference measurements as augmented by the set of augmented measurements that most closely matches the received set of actual measurements; and identifying a location associated with a set of calculated measurements that most closely matches the set of actual measurements wherein the set of calculated measurements is derived from the sets of reference measurements.