|dc.description.abstract||The stethoscope, doctor in one of the most important tools in clinical diagnosis, and its advantages for the non-invasive diagnosis, used as a hearing body sound created by heart, lungs, gastrointestinal tract and other organs so as to determine the body′s disease. Stethoscope since 1816 was invented by French doctor R. Laennec. Now, after nearly two centuries of evolution, from the past early bell stethoscope to present combine sensing component of electronic stethoscope. Due to the development of modern computer technology, electronic stethoscope has in recent years developed into the computerized medical aids, by the way of digital signal analysis using computer, could help doctors diagnose more quickly.
In terms of signal processing systems, electronic stethoscopes can be regarded as a sensing component of acoustic wave, its acoustic frequency response will affect the measurement signal changes. And when doctors conduct clinical measurement will easily be friction sound and environmental noise interference. Doctors in the auscultate may identify noise and the body sound differences, but on the signal analysis using computer, it did not distinguish, especially when external noise and symptoms signals on the same frequency band, the computer will be prone to error of judgment. Therefore, in order to solve these problems on signal processing. This research using the software of finite element analysis (FEA) to simulate the acoustic characteristics of stethoscopes, hoping to achieve better stethoscope design parameters of shapes and materials.
Part in the simulation verification, this research is based on lumped-parameter model of the acoustic system, to explore changes in the frequency response of the acoustic component, and using physical measurements of the interface, measured acoustic frequency response of stethoscope to verify the results of the simulation.