Patent ID: 8582397

Claim:
A method for selecting and modifying localized regions of intensity in waves transmitted through a space occupied by an inhomogeneous medium comprising the steps of: (a) Placing a plurality of transducers in a fixed array adjacent to the space; (b) Placing at least one transducer within the space; (c) Causing a pulse to travel between each of the at least one transducers within the space, at least one location for each transducer for a plurality of locations of transducers, and each transducer in the said fixed array; (d) Recording in a processor having memory time for a leading edge of each such pulse to travel between each transducer in the said fixed array and between each of the transducers within the space, at each location within the space; (e) For each location of each transducer used within the space, the processor executing code to find an approximation, within a fixed finitely parametrized family of functions of transducer position in the array, of the travel time between each location of the said transducer within the space and between the transducers in the fixed array; (f) The processor executing code to construct a mathematical transformation from locations within the space to sets of function parameters of the form used to identify points in the said parametrized family of functions of transducer position in the array, the mathematical transformation giving a set of function parameters for each possible location within the space including at least one location other than a location of a transducer, with the set given for each location within the space that is used in the third step being a set that approximates the set of function parameters found for the said location in step (e); (g) The processor executing code to construct a computable approximate inverse to the transformation; (h) The processor executing code to use the computable approximate inverse to specify, for a fixed or moving point in the said space, signals constructed such that when such constructed signals are emitted from an array co-located with or identical to the said transducer array, the constructed signals cause localized maxima of intensity at or near to the said fixed or moving point; and (i) Emitting such constructed signals from the fixed array as provided by the processor from memory, and said constructed signal including emission directed at the at least one location other than a location of a transducer.