Patent ID: 7280863

Claim:
An apparatus for controlling the movement of a catheter-like tool having a distal end responsive to a magnetic field and configured to be inserted into the body of a patient, comprising: a magnetic field source for generating a magnetic field, said magnetic field source outside the body; a radar system to measure radar data; a sensor system to measure positions of a plurality of fiduciary markers; a user input device for inputting commands to move said distal end; and a system controller for controlling a direction and amplitude of a magnetic field produced by controlling a plurality of currents in electromagnets of said magnetic field source in response to inputs from said user input device, said radar system, and said sensors said system controller configured to compute a location of said distal end by using said radar data to identify contrast between said distal end and body tissues, said contrast resulting from the relative dielectric constants of said distal end and the body tissues.