Machine condition monitoring is one of the most important and a highly

demanding field and had captured the attention of majority of researchers

working on efficient fault detection techniques. Early fault detection in ma-chine condition monitoring not only ensures the smooth operation of the

machinery but also reduces the maintenance cost. Frequency domain anal-ysis is an effective tool for earlier fault detection techniques. To analyze a

signal’s frequency domain properties, the Discrete Time Fourier Transform

is a useful tool. For a certain block length, there is a particular time and

frequency resolution. In case of non stationary signals the Wavelet Trans-form may also be used which does not have a constant time and frequency

resolution for a particular block length. A comparative performance analysis

of both techniques using vibration data is presented on the basis of results

to show the efficiency and scope of each technique. The analysis is based

on advantages and disadvantages of both the techniques over each other to

analyze the stationary and non-stationary vibration signals.