A common method used in tuning adaptivepassive tuned vibration neutralizers is to adjust its resonance frequency to match the excitation frequency, which has the characteristic that the phase angle between its vibrating mass and its support is -90°. A sliding-Goertzel algorithm is presented and demonstrated for extracting the vibration signals at the frequency of interest. The benefit of using the sliding Goertzel algorithm compared to other methods when used in vibration environments with multiple tones is that additional band-pass notch filtering is not required. This algorithm could also be used for adaptive tuned mass dampers, adaptive Helmholtz resonators, and adaptive quarter-wave tubes. © 2012 Elsevier Ltd. All rights reserved.
Howard, C. Q. (2012). A sliding Goertzel algorithm for adaptive passive neutralizers. Journal of Sound and Vibration, 331(9), 1985–1993. https://doi.org/10.1016/j.jsv.2012.01.007