I'm trying to get the cross correlation between two vector samples from flicker noise. The power spectral density is given by: $$N_o\big(1+\frac{f_{corner}}{f}\big),$$ where $N_o$ is the noise floor assumed to $-100dB$, $f_{corner}$ is a parameter of the noise and $f$ is the frequency variable.
From a paper (here), it is already shown that the flicker noise process is non-stationary in the time domain. I have two time-domain vector samples of the process of length $n$ and I need to find the cross correlation matrix between them and observe if the off-diagonal entries are non-zero (check for non-zero correlation). Since the process is non-stationary, the sample values themselves depend on the time they're sampled.
Does this imply that for any two vector samples of the process at different times, the cross-correlation is non-zero?