Howtosignalprocessing
Can instantaneous frequency be negative?
Negative frequency arises often when doing the instantaneous frequency calculation on IMF. The Intrinsic Mode Function characterized by its smoothly oscillatory nature enjoys good properties of Hilbert Transform. The major one is the ruling out of negative frequency which arises often for non-IMF signals.
What is Hilbert transform instantaneous phase?
The Hilbert transform estimates the instantaneous frequency of a signal for monocomponent signals only. A monocomponent signal is described in the time-frequency plane by a single "ridge." The set of monocomponent signals includes single sinusoids and signals like chirps.
