Adaptive focusing and nulling hyperthermia annular and monopole phased array applicators

摘要

An R.F. hyperthermia phased array applicator uses adaptive nulling and focusing with non-invasive electric field probes to control the electric field intensity at selected positions in and around a target body to provide improved heating of solid tumors during hyperthermia treatment. A gradient search or matrix inversion algorithm is used to control the amplitude and phase weighting for the phased array transmit elements of the hyperthermia applicator. A 915 MHz monopole phased array hyperthermia applicator for heating brain tumors has an enclosed vessel including a plurality of monopole transmit antenna elements disposed as a circular arc array on a ground plane which has an aperture for positioning the tumor in proximity to the monopole antenna elements. Adaptive focusing with non-invasive electric field probes is used to maximize the electric field at the tumor site. Parallel plate microwave waveguides are used to direct R.F. energy from the monopole phased array to the tumor site. A microwave transmit and receive module generates amplitude and phase controlled transmit signals for exciting the monopole antenna elements, and receives passive microwave signals from the monopole antenna elements for taking non-invasive radiomerry temperature measurements of the tumor site.