FDTD analysis of power deposition patterns of an array of interstitial antennas for use in microwave hyperthermia

The finite-difference-time-domain (FDTD) method is used to calculate EM power deposition patterns in inhomogeneous tissue models of tumors. The radiated near-field patterns from an array of uniformly and step-insulated interstitial antennas were used as incident fields on the excitation planes to calculate the scattered fields and SAR patterns in tumors. A comparison of data shows that the FDTD solution, in this particular application, overcomes some of the modeling difficulties encountered in the method of moments. Results for some specific tumor geometries are also presented to show the effectiveness of the microwave interstitial heating techniques in treating large tumors. Other advantages of the FDTD method, such as improved accuracy in modeling dielectric interfaces and the ability to model large tumors, are illustrated. >

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