Hello, I am looking for some advice:

I have a system that I am investigating, and I am trying to determine for which parameter values it exhibits which behaviours. There are several different ones, but a typical is that it oscillates. Sometimes it instead displays some kind of “stochastic pulsing” behaviour, where random pulses are triggered (for certain parameters it seems to be some kind of excitable system).

Now to my problem, I have an automated algorithm which classifies the behaviour of the system for a given parameter set, but I am having trouble to robustly determine whenever there’s an oscillation going on (or stochastic pulsing, or maybe just lots of white noise). I figured people here might have some input. How does one determine whenever there’s an oscillation in a signal?

(attaching an image of example system behaviours)