PCG Signal Denoising and Analysis Using Wavelet Transform

The establishment of the clinical electrocardiograph (ECG) by the Dutch physician Willem Einthoven in 1903 marked the beginning of a new era in medical diagnostic techniques, including the entry of electronics into health care. Since then, electronics, and subsequently computers, have become integral components of biomedical signal analysis systems, performing a variety of tasks from data acquisition and preprocessing for removal of artifacts to feature extraction and interpretation. The clinically relevant information in the signal is often masked by noise and interference, and the signal features may not be readily comprehensible by the visual or auditory systems of a human observer. Heart sounds, for example, have most of their energy at or below the threshold of auditory perception of most humans; the interference patterns of a surface electromyography (EMG) signal are too complex to permit visual analysis. This book is an attempt to complete an extensive design of algorithm for denoising the PCG signals. This involves problem identification and its viable solution with the help of programming with MATLAB. Chapter 1 gives a brief description, purpose and outline of the subject