Abstract : The Hilbert/Huang Transform (HHT) is a time-frequency analysis technique that offers higher frequency resolution and more accurate timing of transient and non-stationary signal events than conventional integral transform techniques. Real- time HHT algorithms enable this enhanced signal analysis capability to be used in process monitoring and control applications. This paper compares real-time sifting with adaptive filtering, which we conjectured might be an efficient substitute. While HHT sifting is analogous to filtering, the two techniques produce distinct results. Sifting, for example, will pass purely frequency-modulated signals with low-frequency content, where adaptive filtering will separate the high- and low-frequency content. Sifting was found to introduce aliasing, which is often considered a form of signal corruption.