Adaptive focusing and nulling hyperthermia annular and monopole phased array applicators

A hyperthermia applicator for inducing a temperature rise in a target within a body, comprising

• a plurality of electric field radiators, each for transmitting electric field radiation;
• a plurality of controllable transmit weighting networks, each such network coupled to a respective electric field radiator, each weighting network controlling the phase and amplitude of the electric field radiation transmitted by the respective electric field radiator in response to a respective feedback signal;
• a source of electric field radiation coupled to each electric field radiator through a respective weighting network;
• a plurality of electric field probe elements adapted to be disposed noninvasively along the perimeter of the body between the electric field radiators and the target for detecting electric field radiation from the plurality of radiators;
• and
• a controller coupled to the electric field probe elements for receiving the detected electric field radiation outside the body and generating the respective feedback signals, and for adjusting the feedback signals in response to the detected electric field radiation outside the body so that the electric field radiation is controlled at the target inside the body;
• wherein the controller comprises means for adjusting the feedback signals to minimize the difference in the electric field detected by adjacent electric field probe elements and thereby provide uniform electric field radiation into the body.

A hyperthermia applicator for inducing a temperature rise in a target within a body, comprising

• a plurality of electric field radiators, each for transmitting electric field radiation, comprising a phased array of antenna elements;
• a plurality of controllable transmit weighting networks, each such network coupled to a respective electric field radiator, each weighting network controlling the phase and amplitude of the electric field radiation transmitted by the respective electric field radiator in response to a respective feedback signal;
• a source of electric field radiation coupled to each electric field radiator through a respective weighting network;
• a plurality of electric field probe elements adapted to be disposed non-invasively in an electric field probe array between elements of the phased array and the target for detecting electric field radiation from the plurality of electric field radiators;
• and
• a controller coupled to the electric field probe elements for receiving the detected electric field radiation and generating the respective feedback signals, and for adjusting the feedback signals in response to the detected electric field radiation to provide a particular electric field pattern across the electric field probe array and thereby focus radiation into the target,
• wherein the elements of the phased array are adapted to be disposed symmetrically with respect to a bisector line going from the target to the phased array which bisects the elements of the phased array into symmetric right and left halves, the electric field probe elements of the electric field probe array are adapted to be disposed symmetrically with respect to the bisector line which bisects the electric field probe array into symmetric right and left halves, and the controller adjusts the feedback signals to minimize the difference in the electric field detected by electric field probe elements in the left and right halves of the electric field probe array to balance the electric field pattern with respect to the bisector line, and to minimize the difference in the electric field detected by the electric field probe elements in a direction along the bisector line.

A hyperthermia applicator for inducing a temperature rise in a target located within a living body, comprising

• a phased array of monopole antenna elements,
• a source of electric field radiation coupled to each monopole antenna element,
• and
• an RF reflecting groundplane surface for mounting the monopole antenna elements, the monopole antenna elements being perpendicularly mounted to one side of the RF reflecting groundplane surface, and
• the groundplane surface having an aperture adapted to accommodate a portion of the body to allow positioning the target proximate to the monopole antenna elements.

A method for inducing a temperature rise in a target within a body, comprising the steps of:

• providing a plurality of monopole phased array electric field radiators mounted on a side of an RF reflecting groundplane surface;
• positioning the body containing the target through an aperture in the ground plane surface so that the target is on the same side of the groundplane surface as the electric field radiators;
• coupling a source of electric field radiation to each electric field radiator through a controllable transmit weighting network coupled to a respective electric field radiator;
• controlling the phase and amplitude of the electric field radiation transmitted by the respective electric field radiator with each weighting network in response to a respective feedback signal;
• detecting electric field radiation from the phased array of radiators with a plurality of electric field probe elements disposed noninvasively between the phased array of radiators and the target;
• and
• receiving the detected electric field radiation and generating the respective feedback signals for adjusting the controllable transmit weighting network in response to the detected electric field radiation so that the electric field radiation is controlled at the target inside the body.

A method for inducing a temperature rise in a target within a body, comprising the steps of:

• positioning a phased array of electric field radiators nearby a target;
• coupling a source of electric field radiation to each electric field radiator through a controllable transmit weighting network coupled to a respective electric field radiator;
• controlling the phase and amplitude of the electric field radiation transmitted by the respective electric field radiator with each weighting network in response to a respective feedback signal;
• detecting electric field radiation from the phased array of radiators with a plurality of electric field probe elements disposed non-invasively between the phased array of radiators and the target;
• and
• receiving the detected electric field radiation and generating the respective feedback signals for adjusting the controllable transmit weighting network in response to the detected electric field radiation to minimize the difference in the electric field detected by adjacent electric field probe elements and thereby provide uniform electric field radiation into the body.

A method for inducing a temperature rise in a target within a body, comprising the steps of:

• arranging a plurality of electric field radiators of a hyperthermia phased array symmetrically with respect to a bisector line going from the target to the phased array which bisects the radiators of the phased array into symmetric right and left halves;
• coupling a source of electric field radiation to each electric field radiator through a controllable transmit weighting network coupled to a respective electric field radiator;
• controlling the phase and amplitude of the electric field radiation transmitted by the respective electric field radiator with each weighting network in response to a respective feedback signal;
• detecting electric field radiation from the phased array of electric field radiators with an electric field probe array comprising a plurality of electric field probe elements disposed noninvasively between the phased array of electric field radiators and the target;
• arranging electric field probe elements of the electric field probe array symmetrically with respect to the bisector line which bisects the electric field probe array into symmetric right and left halves;
• and
• receiving the detected electric field radiation and generating the respective feedback signals for adjusting the controllable transmit weighting network in response to the detected electric field radiation so that the electric field radiation is controlled at the target inside the body by adjusting the feedback signals to minimize the difference in the electric field detected by electric field probe elements in the left and right halves of the electric field probe array to balance the electric field pattern with respect to the bisector line, and to minimize the difference in the electric field detected by the electric field probe elements in a direction along the bisector line.

A hyperthermia applicator for inducing a temperature rise in a target within a body, comprising

• a first plurality of electric field radiators, each for transmitting electric field radiation, comprising a phased-array of monopole antenna elements;
• a first RF reflecting groundplane surface disposed adjacent and substantially perpendicular to the monopole antenna elements, the monopole antenna elements being disposed on a side of the RF reflecting groundplane surface;
• a plurality of controllable transmit weighting networks, each such network coupled to a respective monopole antenna element, each weighting network controlling the phase and amplitude of the electric field radiation transmitted by the respective monopole antenna element in response to a respective feedback signal;
• a source of electric field radiation coupled to each monopole antenna element through a respective weighting network;
• at least one electric field probe for detecting electric field radiation from the plurality of monopole antenna elements;
• and
• a controller coupled to the electric field probe for receiving the detected electric field radiation and generating the respective feedback signals, and for adjusting the feedback signals in response to the detected electric field radiation so that the electric field radiation is controlled at the target inside the body.