"Momentary frequency" belongs to the group of adaptive estimators and
computes the momentary frequency of the input signal x by counting
- Adaptation time tm for the mean estimator
- Adaptation time tf for the frequency estimator
Both parameters are in x-axis units.
The parameters for the adaptation times of the estimators determine the adaptation speed and the robustness of the estimation procedure. Lower values result in higher adaptation speeds but then the estimated quantity varies around the true value with high variance. Higher values result in lower adaptation speeds, but then the quantity to be estimated converges more smoothly to the true value in the case of stationary signals. For a momentary frequency analysis of narrow-band signals a time derivation of the Instantaneous phase usually yields better results due to its time resolution.
y = MomFreq(x,tm,tf);
Momentary ARMA bandpower, Momentary ARMA coherence,
ARMA dependence, Momentary ARMA spectrum,
Momentary bandpower, Momentary mean, Momentary power.
Haykin , Grieszbach et al.