Removing Noise from an RF Plasma Signal with the Hilbert-Huang Transform

The Hilbert-Huang Transform uses the method of empirical mode decomposition in which a signal is decomposed into multiple signals called intrinsic mode functions (IMFs). A Hilbert Transform is then applied to these functions in order to obtain instantaneous frequency data. This results in a time dependent distribution of signal amplitudes, known as the Hilbert Spectrum. By applying this transform to a complex or noisy signal, the noise can be isolated and removed from the signal source. This allows for a much cleaner, easier to study signal. In this poster, we will show the theory behind this technique and demonstrate how it can be used to study the plasma pulse form an RF plasma system.