The Design of Digital Collecting System of Heart Sound Signals Based on DSP

Human heart sound signals has the characteristics of strong noise, slight signal, strong randomness and vulnerability to outside interference. De-noising of heart sound signals, therefore, forms the primary basis for achieving non-invasive diagnosis of coronary heart disease. This paper proposes the wavelet Transform method for de-nosing heart sound signals, which has yielded satisfactory results. Accordingly we design a heart sound detection system based on DSP and the HKY sensor to collect the slight heart sound signals, to display in real-time and to save the phonocardiogram. Measurement on different individuals shows that this detection system meets the requirements of human heart sound signals detection. Using this system we are able to differentiate clearly various components of heart sound through the phonocardiogram.