Powder deposition patterns of interstitial microwave hyperthermia applicators having tapered dielectric sheaths

摘要

A coaxial dipole inserted into a cylindrical dielectric sheath is widely used as an interstitial microwave hyperthermia applicator. A means is described here of controlling the current distribution along the dipole and consequently controlling the distribution of the radiated power density by tapering the outside diameter of the dielectric sheath. Numerical results have been obtained for nylon catheters having three different cross-sections using the theory of linear, insulated antennas embedded in electrically dense media.