A correlation processing tool to calculate transient driving signals creating limited diffraction beam-forming in medical diagnosis

This paper proposes and applies a signal processing tool, based on the correlation operator, intended for obtaining approximated solutions of the inversion ultrasonic problem of synthesizing voltage excitations sets in order to form limited diffraction waves, with possible future application for low-cost medical diagnosis. All the calculations analyses were made for an ad-hoc developed, 5-rings 2 MHz annular array transducer, designed for acoustic coupling with water or similar materials as biological tissues. All the simulations performed in this work are based on methods related to transducer impulse responses. The good performances resulting for beam collimation confirm the tool applicability, and moreover suggest the application viability of the proposed procedure for synthesizing, with a reasonable accuracy, other specific driving signals sets to form special acoustic fields devoted to new medical requirements.