Heart sound signal is always contaminated by some kinds of noises, such as breathing sounds, blood flow sound and background noise, etc. To ensure subsequent analysis, the signal preprocessing is very important. In this paper, a heart sound denoising algorithm is introduced based on ensemble empirical mode decomposition (EEMD). The principle of the method is based on the different characteristics between signal and noise. First noisy signal is decomposed by EEMD and obtain the intrinsic mode functions (IMFs). Energy distribution characteristic diagram is acquired. Then the denoised signal is obtained by selecting the appropriate IMFs according to confidence curves of noise. Finally, the experiment is made on simulate signal and the measured heart sound signals. The results indicate the method can effectively reduce the noise of heart sound.
展开▼
