A random telegraph signal of Mittag-Leffler type
  A general method is presented to explicitly compute autocovariance functions for non-Poisson dichotomous noise based on renewal theory. The method is specialized to a random telegraph signal of Mittag-Leffler type. Analytical predictions are compared to Monte Carlo simulations. Non-Poisson dichotomous noise is non-stationary and standard spectral methods fail to describe it properly as they assume stationarity. 
Simone Ferraro, Michele Manzini, Aldo Masoero, Enrico Scalas