V.T.Grinchenko, A.A.Makarenkova Comparing the efficiency of electroacoustic transducers used in the devices for electronic ausculation |
Acoustic bulletin, Vol. 10 ¹ 1, (2007) |
| The paper is devoted to one of the basic problems of auscultation, such as a recording of the respiratory sounds. The factors are analyzed, that determine the processes of sound transition from the body biotissues to contact surface of the mechanical and electroacoustical sensors. It is shown that in the considered systems a mutual conversion of the sound pressure and vibrational velocity occurs. Due to the obtained data, when choosing the type of the electroacoustic device for recording life activity sounds (a microphone or accelerometer), one should take into account the ratio of wave resistances of the biotissues and the sensor's contact surface. The results of the comparative analysis, performed for the characteristics of traditional phonendoscopes and electroacoustic transducers used for electronic auscultation, are presented. The design peculiarities, graduation methods and acoustic features are considered for the contact microphones and accelerometers used in the phonospirographic complexes "CoRA" and electronic phonendoscopes "EPhON". The methods of microphones and accelerometers fixation on the patient's body are pointed out. |
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KEY WORDS: auscultation, phonendoscope, microphone sensor, accelerometer, an acoustic impedance, amplitude-frequency characteristic, signal-to-noise ratio |
| TEXT LANGUAGE: Russian |