The dark path in the center corresponds to the aorta. Figure Captions Figure 1 Catheter Coil, . The current path is not completed. The current periodically charges the poles in reverse polarities. Figure 4 Sectional view of the catheter antenna.
Arrows indicate current-carrying surfaces of the conductors.
Figure 5 Geometry for computation of the input impedance. Current at , passing from the center of the conductor creates an electric field at z on the surface of the conductor. Figure 6 Noise resistance vs antenna length. Main field 4.7 and 1.5 Tesla, 1mm thickness, representative of human body tissue. Figure 7 Sensitivity map of the loopless catheter antenna with arbitrary scaling.