Coherence for order spectra The scipy signal coherence function computes for two time series the coherence as a function of the frequency. For rotating systems however, it is sometimes meaningful to analyze the two recorded signal measurements as order spectra. For an intuitive difference between lines of constant frequency and constant order, I use Figure 2 from Order analysis in ArtemiS Suite - Head acoustics.

What is the most suitable adaptation of the scipy signal coherence in order to get the coherence as a function of the order, instead of the frequency?
The topic is to the best of my knowledge an area of open research. The research contribution which helped me most in solving my problem was: The spectral analysis of cyclo-non-stationary signals. Specifically, the key seems to be:

&quot;In this paper, it is shown that the optimal way of describing
cyclo-non-stationary signals is jointly in the time and the angular
domains.&quot;