Modeling and computer simulation of ultrasound imaging systems and human tissue

Abstract

The performance in B-mode scanning systems depends not only on the acoustic properties of the tissue but also is strongly influenced by the imaging system. In this thesis, a simulator has been developed for the ultrasound linear scan B-mode imaging system. First, a numerical method of calculating field pattern or pulse echo pattern has been presented for a full-aperture system with a given transducer geometry in non-attenuating and attenuating media, based on the measured temporal impulse response for a single transducer element immersed in water, and taking into account the variation of attenuation and acoustic velocity in human tissue. The simulator then models and simulates the receiver subsystems in details using the received pulse echo. In particular, the dynamic inverse filter in order to improve the axial resolution and an unconventional TGC gain function to reduce the SNR deterioration through logarithmic compression are proposed. Finally, simulation and experimental results are presented with discussions.