1. A processor-implemented method for noise cleaning of photoplethysmogram (PPG) signals for estimating blood pressure (BP) of a user; said method comprising: a. extracting, via one or more hardware processors, photoplethysmogram signals from the user using an image capturing device ( 202 ) coupled with a mobile communication device ( 204 ); b. up sampling, via one or more hardware processors, the extracted photoplethysmogram signals using an up sampling module ( 206 ); c. filtering, via one or more hardware processors, the up sampled photoplethysmogram signals using a filtering module ( 208 ); d. removing, via one or more hardware processors, uneven baseline drift of each cycle of the up sampled and filtered photoplethysmogram signals using a baseline drift removal module ( 210 ); e. removing, via one or more hardware processors, outlier cycles of the photoplethysmogram signals by k-means clustering using an outlier removing module ( 212 ); f. modeling, via one or more hardware processors, remaining cycles of the photoplethysmogram signals after removing outlier cycles with a sum of 2 Gaussian functions using a signal modeling module ( 214 ); and g. extracting, via one or more hardware processors, time domain features from originally extracted and modeled photoplethysmogram signals using a feature extraction module ( 216 ) for estimating blood pressure of the user.