Modified Welch Power Spectral Density Computation with Fast Fourier Transform

Spectral analysis finds application in different fields. In vibration monitoring, the spectral content of measured signals give information on the wear and other characteristics of mechanical parts under study. In economics, meteorology, astronomy and several other fields, the spectral analysis may reveal ?hidden periodicities? in the studied data, which are to be associated with cyclic behavior. This paper describes the low-complexity modified algorithm and architectural view to compute the power spectral density (PSD) using the Modified Welch Method. Welch algorithm also used for spectral power estimation. But high computational complexity is the main drawback of Welch method. To reduce the high computational complexity use 50% overlap by computing N/2-point FFT, where N is the length of the window and is merged with previous N/2-point FFT and then calculate the N-point FFT. Frequency-domain windowing operation is preferred for high performance. Parallel FFT approach is the best choice to improve the computational speed.