MODELING METHODOLOGY OF PULSE-ECHO ULTRASOUND SYSTEM FOR MEDICAL IMAGING DIAGNOSTICS

Abstract

A flexible clinical ultrasound system must operate with different transducers, which have characteristic impulse responses and widely varying impedances. The impulse response determines the shape of the high-voltage pulse that is transmitted and the specifications of the front-end electronics that receive the echo

and the impedance determines the specification of the matching network through which the transducer is connected. System-level optimization of these subsystems requires accurate modeling of pulse-echo (two-way) response, which in turn demands a unified simulation of the ultrasonics and electronics. This thesis proposed modeling methodology of pulse-echo ultrasound system for medical imaging diagnostics and the development of pulse-echo ultrasound system simulator in the Matlab/Simulink environment by using the modeling methodology. This simulator is realized by combining Matlab/Simulink models of the high-voltage transmitter, the transmission interface, the acoustic subsystem which includes wave propagation and reflection, the receiving interface, and the front-end receiver. To demonstrate the effectiveness of our simulator, the models are experimentally validated by comparing the simulation results with the measured data from commercial ultrasound system. Proposed pulse-echo ultrasound simulator, which is developed by our modeling methodology, could be used to quickly provide system-level feedback for an optimized tuning of electronic design parameters.