Abstract
Respiration is one of the vital sign used for the index in diagnoses such as sleep apnea syndrome (SAS), pneumonia and heart failure. In this field unconscious measurement is important for acute diagnosis. Our goal is to propose the techniques for unconscious measurement of respiratory signal. For our first trial, we performed the respiratory sound measurement from a neck and analyzed it. The stethoscope which connected a microphone was put on the neck, and it was obtained the sound in breathing. The result of fast Fourier transform (FFT) analysis shows that a frequency band of the breathing was around 400Hz. We obtained respiration sound was extracted with band pass filter having passband between 350 Hz and 450 Hz. The experiment to check a noise affected respiratory sound shows that frequency component of the voice was overlap with respiration. For the next step, we are finding out new analyzing techniques and noise reducing techniques.
