Multimode degenerate mode cavity for microwave hyperthermia treatment

The paper describes a new approach to the selective transmission of electromagnetic energy into a well-defined volume of a dielectric medium, to produce very localised heating within the medium. The concept is based on mode degeneracy in high-order-mode microwave cavities, and constructive field enhancement when several carefully selected degenerate modes are excited simultaneously. A particular embodiment of the cavity system might be a noninvasive hyperthermia procedure designed to raise the temperature of isolated, well-defined, tumours in a human patient or an animal, to eradicate cancer cells in a defined location. Theoretical results based on constructive interference processes for selected modes, which find their basis in well-established antenna-array pattern formulations, are presented.