Temperature Distributions Induced by 2450 MHz Microwave Radiation in a Trilayered Spherical Phantom*

Abstract

ABSTRACTThe properties of phantom modeling materials used in the fabrication of a trilayered spherical phantom and the characteristics of heating patterns induced in the phantom by 2450 MHz microwave radiation are discussed. The techniques used in the preparation of the simulated fat, muscle and brain materials resulted in material mixtures with homogeneous, reproducible and stable dielectric properties. The dielectric properties of these simulated materials exhibited no temperature dependence from 20° to 50°C. The heating patterns in the trilayered spherical phantom were obtained using an inexpensive liquid crystal photographic technique. The characteristics of these heating patterns are shown to be in good qualitative agreement with heating patterns obtained by thermographic techniques and theoretical calculations in homogeneous spherical phantoms. Heating patterns recorded in a bilayered spherical phantom by liquid crystal techniques have a shape and location similar to heating patterns observed in the...