A new approach to accurate frequency extraction from noisy signals

This work proposes a new approach that allows better accuracy in extracting the magnitude and phase of selected frequencies in a noisy environment. An analytical algorithm is derived and is shown to have advantages compared with the conventional FFT analysis. Test results from earthing impedance measurements were used to demonstrate the effectiveness of the proposed approach, and a procedure for on-line condition monitoring of high voltage power systems plant is being developed based on this technique. In the paper, an overview of existing analysis techniques is given together with the details of the proposed approach. Examples of selected frequency extraction are discussed.