The theory and method of human heart sound measuring are researched for intelligent clothing based on fiber Bragg grating.In terms of strain effect of fiber Bragg grating and the vibration principle of round diaphragm

the mathematics model of heart sound sensing is established

and the expression of heart sound sensitivity is deduced.A fiber Bragg grating heart sound sensor is designed and fabricated and its sensitivity is 957.11 pm/kPa in theory.The designed sensor is used to measure human heart sound

the reflected wavelength excursion range is about 70 pm.When the temperature is invariable

the reflected wavelength variety of fiber Bragg grating is mainly caused by heart sound and respiration

and a heart sound extracted arithmetic is proposed based on wavelet decomposition theory.The data processing result shows that when the sampling frequency is 1 kHz

the heart sound data by using the db4 wavelet decomposition has the same characteristics as a standard heart sound sensor.The experimental result proves that the proposed heart sound measurement method and signal processing arithmetic are feasible.