JCS_V1_N1_RP3 Abhishek Misal Dr.G.R. Sinha R.M. Potdar M. Kowar Journal on Communication Engineering and Systems 2277-5242 1 1 49 53 Normalised root mean square, PCG signal, Peak signal to noise ratio, Signal to noise ratio, Wavelet transform This paper address the PCG signals (Phonocardiogram) and their De-noising techniques. The PCG as a kind of weak biological signal under the back ground of strong noise is easily subject to interference from noise of various sources. De-noising of PCG signal therefore, forms the primary basis for achieving non-invasive diagnosis of coronary heart disease. There are various method are available for De-noising the PCG signal but the method is most effective for the PCG signal is very much important. In this paper de- noise the 4 types of PCG signal and check the different parameters and find that which wavelet gives the maximum result for all four types PCG signals. November 2011 - January 2012 Copyright © 2012 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Article.aspx?ArticleId=1740