Title :
Unexpected physical phenomena indicated by FDTD modeling of the Sigma-60 deep hyperthermia applicator
Author :
Reuter, Christopher E. ; Taflove, Allen ; Sathiaseelan, Vythialingam ; Piket-May, Melinda ; Mittal, Bharat B.
Author_Institution :
Res. Site, U.S. Air Force Res. Lab., Rome, NY, USA
fDate :
4/1/1998 12:00:00 AM
Abstract :
We investigate the numerical convergence properties of two-dimensional (2-D) and three-dimensional (3-D) finite-difference time-domain (FDTD) models of the BSD-2000 Sigma-60 annular phased array used for deep hyperthermia. The FDTD modeling data indicate unexpected physical phenomena for the case of Sigma-60 excitation of an elliptical tissue phantom embedded in a circular water bolus. These phenomena include: (1) high-Q energy storage; (2) electromagnetic (EM) mode flipping within the water bolus/phantom; and (3) whispering-gallery transmission of energy to the opposite side of the phantom relative to the exciting dipole pair. We conclude that these phenomena substantially impact the FDTD numerical modeling of this system, and further conclude that the whispering-gallery effect can impact clinical applications of the Sigma-60
Keywords :
convergence of numerical methods; finite difference time-domain analysis; hyperthermia; microwave heating; BSD-2000 Sigma-60 annular phased array; FDTD model; circular water bolus; clinical application; deep hyperthermia applicator; dipole pair excitation; electromagnetic mode flipping; elliptical tissue phantom; energy storage; numerical convergence; whispering-gallery transmission; Convergence of numerical methods; Energy storage; Finite difference methods; Hyperthermia; Imaging phantoms; Numerical models; Phased arrays; Time domain analysis; Two dimensional displays; Water storage;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
