Frequency optimization of focused microwave hyperthermia applicators

We study the design optimization of focused microwave hyperthermia applicators. For a fixed aperture size and a given penetration depth, an optimal frequency is determined by considering the tradeoff between heat localization and medium loss. At this optimal frequency, the deficiencies of conventional applicators; namely, large spillover, shallow penetration, and excessive surface heating, can be significantly compensated by focused applicators.