井出 正男, 竹内 真一

Masao lDE, Shinichi TAKEUCHI

武蔵工業大学電子通信工学科

Department of Electronics and Communication Engineering. Musashi Institute of Technology

キーワード : distance resolution, propagation properties, simulation, degradation, signal processing

Performance, especially distance resolution, of ultrasonic diagnostic equipment has been improved, because transducer capable of radiating sharp pulse has been developed. Since ultrasonic propagation properties of tissues have the frequency dependence, pulse wave form degrades by propagating in tissue.
In this study, simulation of the degradation of the pulse was carried out by using digital computer. Obtained results showed that the frequency dependence of the propagation properties of tissue was one of the significant cause of the distance resolution degradation. Transmission experiment of sharp ultrasonic pulse was carried out in the model medium of tissue, and the results of simulation were testified by this experiment.
In order to improve the distance resolution of ultrasonic diagnostic equipment, degraded pulse must be restored to original state by signal processing. Degraded pulse wave form can be restored to original state by the inverse operation of the simulation.